CTMX

This article first appeared on GuruFocus. Release Date: August 06, 2026 For the complete transcript of the earnings call, please refer to the full earnings call transcript. CytomX Therapeutics Inc (NASDAQ:CTMX) is aggressively advancing its lead asset, Varetta M, a first-in-class EPCAM-targeting ADC, with a clear path toward a registrational study in late-line colorectal cancer (CRC) by the first half of 2027. The company is broadening Varetta M's potential by initiating phase 1 expansion cohorts in additional GI cancers (gastric, pancreatic, and biliary tract), positioning it as a potential pan-tumor therapy. Strong clinical progress is highlighted by preliminary PFS data of 6.8-7.1 months at the top two doses in late-line CRC, which compares favorably to existing benchmarks of 4.5-5.5 months for standard of care. The company has a solid financial runway, projecting cash to last until at least the second half of 2028, which supports advancing Varetta M through key clinical milestones. The expanded collaboration with Regeneron, including a $37 million payment, validates CytomX's proprietary masking technology and provides additional non-dilutive funding. The company is strengthening its leadership team with key appointments in regulatory affairs, legal, and a new board member with deep GI oncology expertise, preparing for late-stage development. Total revenue decreased significantly to $1.4 million in Q2 2026 from $18.7 million in Q2 2025, due to the conclusion of major collaborations with BMS and Aelis. Operating expenses increased to $25.2 million in Q2 2026 from $19.9 million in Q2 2025, driven by higher R&D costs for manufacturing and personnel, which could pressure future cash flow. The company faces a key safety risk with Varetta M, as the rate of grade 3 diarrhea is a concern; while initial prophylaxis data is encouraging, the acceptable threshold is up to 20%, which could limit its use in earlier lines of therapy. The development strategy for the first registrational study is still undecided (third vs. fourth line), and the company is awaiting more mature data, including overall survival, to make a final decision. The company is enrolling unselected patients in CRC but will need to screen for EPCAM expression in pancreatic and biliary tract cancers, which could slow enrollment and limit the addressable patient population in those indications. The initial data for the bevacizumab combination and the new phase 1/2 trial in second-line CRC will not be available until the first half of 2027, leaving a significant gap in clinical updates. Warning! GuruFocus has detected 4 Warning Signs with CTMX. Is CTMX fairly valued? Test your thesis with our free DCF calculator. Q: What is the bar for success or a good outcome on median PFS for the monotherapy readout, and what are your thoughts on the control arm for the registrational study? Would the FDA require Lonsurf plus Bev as a comparator? A: Sean McCarthy (CEO): We plan to communicate data when we have an initial read on PFS for the optimization cohorts, which were fully enrolled by the end of April. Our baseline assumption for the first registrational study is that the primary endpoint will be overall survival. In the fourth line, the most likely comparator would be fruquintinib or regorafenib, or perhaps Physician's Choice. In the third line, we assume the comparator would most likely be bevacizumab plus Lonsurf. For benchmarks, fourth-line monotherapy treatments have response rates of 1-2%, a few months of PFS, and 5-6 months of OS. With Bev plus Lonsurf in the third line, PFS is 4.5-5.5 months and OS is 9-10 months. We previously reported preliminary PFS of 6.8-7.1 months at the TOP2 doses (8.6 and 10 mg/kg), which we are very encouraged by. Q: Could you comment on how you're approaching dose selection for the new GI cancer expansion cohorts and the bevacizumab combination study in colorectal cancer? Are you utilizing the same prophylaxis strategy? A: Sean McCarthy (CEO): We are excited to move into additional GI indications with Varetta M, as EPCAM is expressed in these and many other solid tumors. Dose selection for the monotherapy cohorts is informed by the escalation, expansion, and optimization work done in colorectal cancer. For the bevacizumab combination, we are exploring Q2 week and Q4 week schedules to align with bevacizumab's clinical schedule. We started at meaningful doses of Varetta M rather than going back to the beginning of dose escalation. We are on track to present initial data in the first half of next year. Yes, we are utilizing the same loperamide and budesonide prophylaxis strategy in the Bev combo study. Q: What do you see as the path forward for the combo studies in earlier-line CRC, and when could we expect data? What are the potential requirements for future studies? A: Sean McCarthy (CEO): The bevacizumab combination is foundational given how integral Bev is across multiple lines of CRC treatment. It will open up opportunities for a potential third-line study and enable work in first and second-line settings over time. We are also excited to start the chemo combination with 5-FU later this year, designed to bring Varetta M into the second line to replace irinotecan, where FOLFIRI is most commonly used. It's too early to comment on potential registrational paths in earlier lines, but these combination studies unlock enormous potential in the coming years. Q: With the $37 million payment from Regeneron received in Q3, would that be recognized fully in revenues in the third quarter? A: Chris Ogden (CFO): We are thrilled to expand the collaboration with Regeneron, which reflects the foundational science. The $37 million payment is for two additional programs, taking our pro forma cash to about $367 million. This payment will be recognized as we do the work and make progress. Since these are preclinical projects, we expect the recognition to play out over a few years at least. Q: There is a fear that if the grade 3 diarrhea rate is on the higher end of the 10-20% range in the year-end update, there could be a risk to moving the product upstream. How would you respond to this pushback? A: Sean McCarthy (CEO): We are highly focused on this area as we move through the monotherapy dose optimization cohorts. In our March data update, the prophylaxis strategy of loperamide and budesonide was very encouraging, bringing the grade 3 diarrhea rate down to 10%. The 20% number is what we've been discussing, but it's all about risk-benefit. Given the high unmet need in late-line and even second-line CRC, and the impressive activity we've seen with Varetta M, we believe the risk-benefit profile will be favorable. We will continue to learn about the etiology, time to onset, and impact of prophylaxis to manage this adverse event over time. Q: Are you targeting a certain amount of follow-up time for the CRC late-line update by year-end, given that the study was enrolled in April? Also, what are your thoughts on EPCAM expression levels in biliary tract and pancreatic ductal cancer? A: Sean McCarthy (CEO): For the next update, we are working towards an update across the entire 113-patient study, including data from the 40 patients in dose optimization. Our goal is to communicate data when it is sufficiently mature to have a preliminary estimate of progression-free survival. We will also provide the first look at overall survival from the escalation and expansion phases, which will be foundational for our decision on the first pivotal study. Regarding EPCAM expression, it is expressed at some level in just about all patients. EPCAM-high patients are about 50-60% in pancreatic and biliary tract cancers. We plan to screen for EPCAM expression in these tumor types as a starting point, though we haven't disclosed the cutoff yet. In gastric and GEJ cancer, we expect to enroll an unselected population given the high percentage of EPCAM-expressing tumors. Q: As you get closer to the year-end update and the planned registration start in the first half of next year, what pieces of the puzzle are becoming clearer? Have you met with the FDA, and what needs to be resolved before finalizing the registration population and endpoints? A: Sean McCarthy (CEO): We are very focused on this question and anticipate multiple interactions with the FDA across the program in the back half of 2026. We continue to see tremendous opportunity in either the fourth-line or third-line settings. We need to pin down what those patient populations look like, the relevant comparator arm in each, and as data matures, the sizing of those studies. We will make a data-driven decision, take our recommendations to the FDA, and move forward with the first pivotal study in the first half of next year. Everything remains on track. Q: How are you approaching prior irinotecan or prior TOP1 inhibitor exposure in the non-CRC cohorts? A: Sean McCarthy (CEO): In the late-line patients treated to date across the phase 1 study, everyone has seen irinotecan over their treatment journey, which is For the complete transcript of the earnings call, please refer to the full earnings call transcript.

Interested in CytomX Therapeutics, Inc.? Here are five stocks we like better. Varseta-M remains CytomX’s primary focus: The Phase I monotherapy study has enrolled 113 patients, with a broader clinical update expected by the end of 2026 and a potential registrational study planned for the first half of 2027. CytomX is expanding Varseta-M into earlier-line colorectal cancer through combinations with bevacizumab, 5-fluorouracil and leucovorin, while also launching Phase I cohorts in gastric, pancreatic and biliary tract cancers. Financially, the company reported $330.3 million in cash and investments at June 30 and received a subsequent $37 million Regeneron payment, extending its expected cash runway into at least the second half of 2028 despite lower quarterly revenue and higher operating expenses. CytomX Therapeutics (NASDAQ:CTMX) said its second-quarter focus remained on advancing Varseta-M, an EpCAM-targeting antibody-drug conjugate being developed for metastatic colorectal cancer, while expanding the program into combination regimens and additional gastrointestinal cancers. Chief Executive Officer and Chairman Sean McCarthy said the company has enrolled 113 patients in its overall Phase I Varseta-M monotherapy study, spanning dose escalation, expansion and optimization cohorts. Enrollment in dose optimization was completed in April, with 40 patients enrolled across 8.6 mg/kg and 10 mg/kg dose levels using adjusted ideal body weight dosing. → 3 Drone Stocks That Should Soar After the Summer Slump The company plans to provide a Phase I update by the end of 2026 covering the broader 113-patient study. The update is expected to focus on dose selection for monotherapy and support planning for a first registrational study, which CytomX aims to begin in the first half of 2027. McCarthy said CytomX continues to view both third-line and fourth-line colorectal cancer as potential settings for Varseta-M’s initial registrational study, with the eventual decision depending on emerging clinical data. The company expects to communicate its strategy later in 2026. → Meta’s Earnings Drop Shows Wall Street Wants More Than Ad Growth During the question-and-answer session, McCarthy said the company expects its year-end update to include a preliminary progression-free survival assessment from the dose-optimization cohorts, as well as an initial look at overall survival from patients in the dose-escalation and expansion portions of the study. He said CytomX’s baseline assumption is that overall survival would serve as the primary endpoint in a late-line colorectal cancer registrational study. Potential comparators would differ by treatment setting. In fourth-line disease, the company is evaluating options including fruquintinib, regorafenib or physician’s choice, while a third-line study would most likely use bevacizumab plus LONSURF as a comparator, McCarthy said. → Jersey Mike's Serves Fresh Gains After IPO Stumble McCarthy cited benchmarks discussed on the call for late-line treatments, including low-single-digit response rates and several months of progression-free survival in fourth-line disease. For third-line bevacizumab plus LONSURF, he referenced progression-free survival of roughly 4.5 to 5.5 months and overall survival of nine to 10 months. CytomX previously reported preliminary progression-free survival of 6.8 to 7.1 months at the 8.6 mg/kg and 10 mg/kg dose levels in March. CytomX is also evaluating Varseta-M in combination with bevacizumab, a component of colorectal cancer treatment regimens across earlier and later lines of therapy. The ongoing Phase I cohort is studying every-two-week and every-four-week schedules designed to align with bevacizumab treatment schedules. The company is continuing to enroll late-line patients in the bevacizumab combination study and expects to move toward earlier-line patients after selecting a go-forward dose and schedule. Initial clinical data are expected in the first half of 2027. McCarthy said the company is using the same loperamide and budesonide prophylaxis strategy in the bevacizumab combination cohort as in monotherapy dose optimization. He said CytomX had previously reported that grade 3 diarrhea after the first several months of prophylaxis experience had been reduced to 10%. The company plans to initiate another Phase I/II study in the fourth quarter that will evaluate escalating Varseta-M doses in combination with bevacizumab, 5-fluorouracil and leucovorin in second-line colorectal cancer. CytomX said the study is intended to support its goal of replacing irinotecan with Varseta-M in earlier-line therapy. McCarthy said all patients treated with Varseta-M to date have received irinotecan as part of their treatment history because they were in late-line settings. The planned second-line combination study is expected to help the company gain experience with Varseta-M in irinotecan-naive patients over time. CytomX announced plans to initiate Phase I expansion cohorts for Varseta-M in gastric and gastroesophageal junction cancer, pancreatic ductal adenocarcinoma and biliary tract cancer. The company plans to enroll about 20 patients in each tumor type to evaluate antitumor activity and safety before determining potential next steps. The company expects to enroll an unselected population in gastric and gastroesophageal junction cancer because of the expected prevalence of EpCAM expression. It plans to screen pancreatic and biliary tract cancer patients for EpCAM expression. McCarthy said EpCAM is expressed at some level in nearly all pancreatic and biliary tract cancer patients based on published literature and the company’s studies using its immunohistochemistry assay. He said approximately 50% to 60% of patients may be considered EpCAM-high, depending on the definition, though CytomX has not disclosed its cutoff for high expression. “We think it makes sense to at least start” with higher EpCAM-expressing patients in pancreatic and biliary tract cancers, McCarthy said, while noting the company is still learning about the relationship between EpCAM levels and Varseta-M activity. CytomX also reported progress for CX-801, its masked interferon alfa-2b program in checkpoint-refractory melanoma. The monotherapy portion of the Phase I study has reached its fourth dose level, while the combination study with KEYTRUDA has cleared its third dose level and continues enrollment. McCarthy said CX-801 monotherapy has been generally well tolerated to date, including at doses exceeding levels achieved with commercially available unmasked interferon alfa-2b. Initial clinical data from the melanoma study are expected in the first half of 2027. During the quarter, CytomX announced an expanded collaboration with Regeneron focused on next-generation masked bispecific immunotherapies. Chief Financial Officer Chris Ogden said CytomX received a $37 million payment from Regeneron in July after the selection of two additional targets under the collaboration. Ogden said the payment was not included in CytomX’s June 30 cash balance and will be recognized as revenue over time as work is performed on the preclinical programs. Cash, cash equivalents and investments totaled $330.3 million as of June 30, compared with $346.7 million as of March 31. The June 30 balance did not include the $37 million July payment from Regeneron. Ogden said pro forma cash was about $367 million after that payment. Total revenue was $1.4 million, down from $18.7 million in the second quarter of 2025, primarily due to the conclusion of the Bristol Myers Squibb collaboration in 2025 and the Astellas collaboration in the first half of 2026. Operating expenses increased to $25.2 million from $19.9 million a year earlier. Research and development expense rose to $17.6 million, driven primarily by Varseta-M manufacturing, personnel costs and other research and development expenses. General and administrative expense increased to $7.6 million from $6.6 million, primarily because of higher consulting costs. Ogden said CytomX expects its existing balance sheet to provide cash runway into at least the second half of 2028, supporting its planned registrational study for Varseta-M, earlier-line combination development and expansion into other EpCAM-expressing cancers. CytomX Therapeutics, Inc is a clinical-stage biopharmaceutical company focused on the discovery and development of next-generation therapeutics based on its proprietary Probody® platform. The company engineers masked antibody prodrugs that remain inactive in healthy tissue but are selectively activated in the tumor microenvironment. This approach is designed to enhance the safety and tolerability of antibody-based therapies, particularly those targeting immuno-oncology pathways. At the core of CytomX's pipeline is Pacmilimab (CX-072), an anti–PD-L1 Probody therapeutic currently undergoing clinical evaluation for multiple solid tumor indications. This instant news alert was generated by narrative science technology and financial data from MarketBeat in order to provide readers with the fastest reporting and unbiased coverage. Please send any questions or comments about this story to [email protected]. The article "CytomX Therapeutics Q2 Earnings Call Highlights" was originally published by MarketBeat. View MarketBeat's top stocks for August 2026.

Varsetatug masetecan (“Varseta-M”) Program: - Phase 1 monotherapy update in advanced colorectal cancer (CRC) expected by the end of 2026. Registrational study planned for initiation in 1H 2027 - - Phase 1 study in combination with bevacizumab in 3L+ mCRC ongoing. Phase 1/2 chemotherapy combination study focused in 2L mCRC initiating in Q4 2026 - - Phase 1 monotherapy expansion cohorts initiating in Q3 2026 in gastric and gastroesophageal junction (GEJ), EpCAM-selected pancreatic ductal adenocarcinoma (PDAC), and EpCAM-selected biliary tract cancer (BTC) - Corporate: - Regeneron alliance in masked bispecific immunotherapies expanded to additional targets - - Board of directors and executive leadership team strengthened with additions of Charles Fuchs, MD, Mamata Gokhale, Ph.D. and Alejandra Carvajal, JD - - Company to host conference call today at 5 p.m. ET / 2 p.m. PT - SOUTH SAN FRANCISCO, Calif., Aug. 06, 2026 (GLOBE NEWSWIRE) -- CytomX Therapeutics, Inc. (Nasdaq: CTMX), a leader in the field of masked, conditionally activated biologics, today announced Q2 2026 financial results and provided a business update. “CytomX had a productive second quarter as we advanced and broadened the Varseta-M program, the only EpCAM-directed antibody drug conjugate (ADC) in clinical development and a potentially best-in-class ADC for colorectal cancer. As we drive Varseta-M towards its first registrational study in late-line CRC, we are also accelerating our broader vision of earlier line utilization in CRC combination regimens, while also initiating development in additional gastrointestinal cancers of high unmet need,” said Dr. Sean McCarthy, chairman and CEO of CytomX Therapeutics. “Additionally, this quarter, we were excited to announce a significant expansion of our Regeneron collaboration in bispecific immunotherapies, further validating our PROBODY® therapeutic platform expertise. We are also pleased to be strengthening the CytomX team and board of directors for CytomX’s next phase of growth as we remain highly focused on making a meaningful difference for patients and stakeholders over the near- and long-term.” Pipeline Program Updates: Varsetatug masetecan (EpCAM PROBODY Topo-1 ADC, CX-2051) Varseta-M Monotherapy CRC: Varseta-M CRC Combinations: Varseta-M Non-CRC Indication Expansion: CX-801 (PROBODY Interferon alpha-2b) The CX-801 Phase 1 study in advanced melanoma is ongoing. The CX-801 monotherapy dose escalation portion of the study has reached the fourth dose level. CX-801 monotherapy has been generally well tolerated at dose levels exceeding the approved dose of unmasked IFNα2b.2 In May 2025, Phase 1 dose escalation of CX-801 in combination with KEYTRUDA® (pembrolizumab) was initiated. Dose escalation of CX-801 in combination with KEYTRUDA® has cleared the third dose level and enrollment into the study continues. Initial clinical data for CX-801 in combination with KEYTRUDA® in advanced melanoma is expected in the first half of 2027. KEYTRUDA® is a registered trademark of Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA. Corporate and Financial: Strengthened Board of Directors and Leadership for Next Phase of Growth Regeneron Collaboration Expansion: Financial: Q2 2026 Financial Results: Cash, cash equivalents and investments totaled $330.3 million as of June 30, 2026, compared to $346.7 million as of March 31, 2026. Total revenue was $1.4 million for the quarter ended June 30, 2026, compared to $18.7 million for the second quarter of 2025. The decrease in revenue was driven primarily by the completion of the Company’s performance obligation during 2025 in the collaborations with Bristol Myers Squibb and lower research activities in the Astellas collaboration which concluded in the second quarter of 2026. Total operating expense for the quarter ended June 30, 2026 was $25.2 million compared to $19.9 million for the quarter ended June 30, 2025, an increase of $5.3 million. Research and development expenses increased by $4.3 million during the quarter ended June 30, 2026, to $17.6 million compared to $13.3 million for the quarter ended June 30, 2025. Research and development expenses increased primarily due to manufacturing activities for Varseta-M as well as increased personnel related costs and general research and development expenses. General and administrative expenses increased by $1.0 million during the quarter ended June 30, 2026, to $7.6 million, compared to $6.6 million for the quarter ended June 30, 2025. Increased general and administrative expenses were primarily driven by higher consulting expenses and higher rent expenses. About CytomX Therapeutics, Inc.CytomX is a clinical-stage, oncology-focused biopharmaceutical company focused on developing novel conditionally activated, masked PROBODY® therapeutics designed to be localized to the tumor microenvironment. By pioneering a novel pipeline of localized biologics, powered by its PROBODY therapeutic platform, CytomX’s vision is to create safer, more effective therapies for the treatment of cancer. CytomX’s robust and differentiated pipeline comprises therapeutic candidates across multiple treatment modalities including antibody-drug conjugates (“ADCs”), cytokines and T-cell engagers. CytomX’s clinical-stage pipeline includes varsetatug masetecan (Varseta-M; CX-2051) and CX-801. Varseta-M is a masked, conditionally activated ADC armed with a topoisomerase-1 inhibitor payload and directed toward epithelial cell adhesion molecule (EpCAM). EpCAM is a highly expressed tumor antigen that has previously been undruggable due to expression on normal tissues. Varseta-M is designed to open a therapeutic window for this high potential target and is initially being developed for the treatment of metastatic colorectal cancer. Varseta-M was discovered in collaboration with ImmunoGen, now part of AbbVie. CX-801 is a masked interferon alpha-2b PROBODY® cytokine with broad potential applicability in traditionally immuno-oncology sensitive as well as insensitive (cold) tumors. CX-801 is initially being developed for the treatment of metastatic melanoma. CytomX has established strategic collaborations with multiple leaders in oncology, including Amgen, Regeneron and Moderna. For more information about CytomX and how it is working to make conditionally activated treatments the new standard-of-care in the fight against cancer, visit www.cytomx.com and follow us on LinkedIn and X (formerly Twitter). CytomX Therapeutics Forward-Looking StatementsThis press release includes forward-looking statements. Such forward-looking statements involve known and unknown risks, uncertainties and other important factors that are difficult to predict, may be beyond CytomX’s control, and may cause the actual results, performance, or achievements to be materially different from any future results, performance or achievements expressed or implied in such statements, including those related to the future potential of partnerships or collaboration agreements and projected cash runway. Accordingly, you should not rely on any of these forward-looking statements, including those relating to the potential benefits, safety and efficacy or progress of CytomX’s or any of its collaborative partners’ product candidates, including varsetatug masetecan (Varseta-M) and CX-801, the potential benefits or applications of CytomX’s PROBODY® therapeutic platform, CytomX's planned interactions with the U.S. Food and Drug Administration and the ability to align on a potential registrational study design and regulatory pathway for Varseta-M, CytomX’s or its collaborative partners’ ability to develop and advance product candidates into and successfully complete clinical trials, including the ongoing and planned clinical trials of Varseta-M and CX-801 and the timing of initial and ongoing data availability for CytomX’s clinical trials, including Varseta-M and CX-801, and other development milestones. Risks and uncertainties that contribute to the uncertain nature of the forward-looking statements include: the unproven nature of CytomX’s novel PROBODY® therapeutic technology; uncertainties around the Company’s ability to raise sufficient funds to carry out its planned research and development; CytomX’s clinical trial product candidates are in the initial stages of clinical development and its other product candidates are currently in preclinical development, and the process by which preclinical and clinical development could potentially lead to an approved product is long and subject to significant risks and uncertainties, including the possibility that the results of preclinical research and early clinical trials, including initial Varseta-M clinical trial results, may not be predictive of future results; the possibility that CytomX’s clinical trials will not be successful; the possibility that current preclinical research may not result in additional product candidates; the possibility that CytomX may not be able to realize the full potential of its collaborations; CytomX’s dependence on the success of Varseta-M and CX-801; CytomX’s reliance on third parties for the manufacture of the Company’s product candidates; possible regulatory developments in the United States and foreign countries, including China and the European Union; and the risk that CytomX may incur higher costs than expected for research and development. Additional applicable risks and uncertainties include those relating to CytomX’s preclinical research and development, clinical development, and other risks identified under the heading "Risk Factors" included in CytomX’s Quarterly Report on Form 10-Q filed with the SEC on August 6, 2026. The forward-looking statements contained in this press release are based on information currently available to CytomX and speak only as of the date on which they are made. CytomX does not undertake and specifically disclaims any obligation to update any forward-looking statements, whether as a result of any new information, future events, changed circumstances or otherwise. PROBODY is a U.S. registered trademark of CytomX Therapeutics, Inc. All other trademarks are the properties of their respective owners.Company Contact:Chris OgdenSVP, Chief Financial [email protected] Investor Contact:Precision AQ Stephanie [email protected] Media Contact:Precision AQColleen [email protected] __________________(1)    The condensed balance sheet as of December 31, 2025 was derived from the audited financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2025. 1 Dose Optimization utilizes adjusted ideal body weight dosing2 Merck & Co., Inc. (2018). Sylatron (peginterferon alfa-2b) prescribing information. U.S. Food and Drug Administration

SOUTH SAN FRANCISCO, Calif., July 30, 2026 (GLOBE NEWSWIRE) -- CytomX Therapeutics, Inc. (Nasdaq: CTMX), a leader in the field of masked, conditionally activated biologics, today announced that it will report second quarter financial results on Thursday, August 6, 2026, after the close of U.S. markets. Following the announcement, the Company will host a conference call and webcast at 5:00 p.m. ET / 2:00 p.m. PT. Participants may access the live webcast of the conference call from the Events and Presentations page of CytomX’s website at https://ir.cytomx.com/events-and-presentations. Participants may register for the conference call here and are advised to do so at least 10 minutes prior to joining the call. An archived replay of the webcast will be available on the Company’s website. About CytomX Therapeutics, Inc.CytomX is a clinical-stage, oncology-focused biopharmaceutical company focused on developing novel conditionally activated, masked PROBODY® therapeutics designed to be localized to the tumor microenvironment. By pioneering a novel pipeline of localized biologics, powered by its PROBODY therapeutic platform, CytomX’s vision is to create safer, more effective therapies for the treatment of cancer. CytomX’s robust and differentiated pipeline comprises therapeutic candidates across multiple treatment modalities including antibody-drug conjugates (“ADCs”), cytokines and T-cell engagers. CytomX’s clinical-stage pipeline includes varsetatug masetecan (Varseta-M; CX-2051) and CX-801. Varseta-M is a masked, conditionally activated ADC armed with a topoisomerase-1 inhibitor payload and directed toward epithelial cell adhesion molecule (EpCAM). EpCAM is a highly expressed tumor antigen that has previously been undruggable due to expression on normal tissues. Varseta-M is designed to open a therapeutic window for this high potential target and is initially being developed for the treatment of metastatic colorectal cancer. Varseta-M was discovered in collaboration with ImmunoGen, now part of AbbVie. CX-801 is a masked interferon alpha-2b PROBODY® cytokine with broad potential applicability in traditionally immuno-oncology sensitive as well as insensitive (cold) tumors. CX-801 is initially being developed for the treatment of metastatic melanoma. CytomX has established strategic collaborations with multiple leaders in oncology, including Amgen, Regeneron and Moderna. For more information about CytomX and how it is working to make conditionally activated treatments the new standard-of-care in the fight against cancer, visit www.cytomx.com and follow us on LinkedIn and X (formerly Twitter). Company Contact:Chris OgdenSVP, Chief Financial [email protected] Investor Contact:Precision AQ Stephanie [email protected] Media Contact:Precision AQColleen [email protected]

Track your investments for FREE with Simply Wall St, the portfolio command center trusted by over 7 million individual investors worldwide. Regeneron Pharmaceuticals (REGN) has been back in focus after expanding its cancer therapy partnership with CytomX Therapeutics, a deal with up to $4b in potential milestones, alongside highly favorable Lynozyfic trial results in light chain amyloidosis. See our latest analysis for Regeneron Pharmaceuticals. Despite the Oncology headlines, the stock’s recent momentum has cooled, with the 30 day share price return down 10.47% and the 90 day share price return down 17.26%, even as the 1 year total shareholder return is 30.87%. If Regeneron’s pipeline has caught your attention, this is also a useful moment to scan other healthcare names using a focused screener for 40 healthcare AI stocks So with the stock giving up ground in recent months, even as Regeneron posts revenue and net income growth and trades at a reported 72% intrinsic discount, is this a genuine opportunity, or is the market already pricing in future growth? Regeneron’s most followed narrative points to a fair value of $875.31 versus the last close of $628.73, framing the recent pullback against a still bullish long term story. Read the complete narrative. Curious what has to happen for that higher fair value to make sense? The narrative focuses on a combination of faster revenue, wider margins, and a richer future earnings multiple. The exact mix of those levers may surprise you. On the numbers, the narrative leans on analyst expectations that Regeneron can lift both its top line and profitability over time, while also supporting a higher P/E multiple than the wider US biotechs sector and a discount rate of 7.21% in the cash flow model. For you, the key question is whether revenue, earnings and margins can track those assumptions closely enough to justify the gap between the current $628.73 share price and the $875.31 fair value embedded in this story. Result: Fair Value of $875.31 (UNDERVALUED) Have a read of the narrative in full and understand what's behind the forecasts. However, this depends on EYLEA holding up against tougher competition and pricing pressure, as well as on heavier R&D and manufacturing spending actually translating into commercially successful drugs. Wall Street's queuing for one rocket. While SpaceX counts down to its IPO, other companies tied to the new space race are already in orbit. → 20 Compelling Space Companies watchlist · Global Space Race Investing Ideas screener · Scan the sector by valuation on Rocket Lab's valuation page. With sentiment clearly split between recent share price weakness and an optimistic long term story, this is a good time to review the data for yourself, move quickly if you need to, and weigh those potential upsides against your own risk tolerance by checking the 4 key rewards If you stop with just one stock, you could miss out on other opportunities that fit your goals even better, so put the Simply Wall Street Screener to work. Target income potential by reviewing companies that feature 10 dividend fortresses and see which payouts and histories line up with your expectations. Hunt for mispriced opportunities using our pick of screener containing 22 high quality undiscovered gems that combine solid fundamentals with less crowded investor attention. Prioritise resilience by checking 64 resilient stocks with low risk scores so you can focus on companies that may better match a more conservative approach. This article by Simply Wall St is general in nature. We provide commentary based on historical data and analyst forecasts only using an unbiased methodology and our articles are not intended to be financial advice. It does not constitute a recommendation to buy or sell any stock, and does not take account of your objectives, or your financial situation. We aim to bring you long-term focused analysis driven by fundamental data. Note that our analysis may not factor in the latest price-sensitive company announcements or qualitative material. Simply Wall St has no position in any stocks mentioned. Companies discussed in this article include REGN. Have feedback on this article? Concerned about the content? Get in touch with us directly. Alternatively, email [email protected]

Image source: The Motley Fool. Monday, Mar. 16, 2026 at 8 a.m. ET Chief Executive Officer and Chairman — Sean McCarthy, D.Phil. Chief Medical Officer — Yu-Waye Chu, M.D. Vice President, Investor Relations and Corporate Communications — Chris Ogden Need a quote from a Motley Fool analyst? Email [email protected] Chris Ogden: Thank you. Good morning, and thank you for joining us. Before we begin, I would like to remind everyone that during this call, we will be making forward-looking statements. Because forward-looking statements relate to the future, they are subject to inherent uncertainties and risks that are difficult to predict and many of which are outside of our control. Important risks and uncertainties are set forth in our most recent public filings with the SEC at sec.gov. We undertake no obligation to update any forward-looking statements, whether as a result of new information, future developments or otherwise. Earlier today, we issued a press release that includes a summary of our 2025 financial results and progress at CytomX. Additionally, this morning, we are excited to announce positive Phase I dose expansion data for Varseta-M in patients with late-line colorectal cancer. The focus of our call today will be the Phase I expansion data update for Varseta. For details on the company's 2025 financial results and other pipeline updates, we encourage everyone to read today's press releases and the associated materials, which have been filed with the SEC. Additionally, the press releases, a recording of this call and our SEC filings can be found under the Investors and News section of our website. With me on the call today are Dr. Sean McCarthy, CytomX' Chief Executive Officer and Chairman; and Dr. Wayne Chu, CytomX' Chief Medical Officer. Sean will provide introductory remarks regarding the clinical data and Varseta program strategy, and Wayne will then walk through the clinical data. We will then wrap up with concluding remarks and a Q&A session. With that, I'll now turn the call over to Sean for opening remarks. Sean McCarthy: Thanks, Chris, and good morning, everyone. It's really a pleasure to be here with you all. The major focus of today's discussion will be an exciting update on Phase I data for our EpCAM-targeting PROBODY antibody drug conjugate for varsetatug masetecan, otherwise known as Varseta-M or Varseta. There's been a very high level of interest in this program since our first data disclosure in May last year, in which we shared a strong start with the clinical development of this first-in-class ADC for colorectal cancer. We'll refer to colorectal cancer during this presentation as CRC. In today's update, we want to share the terrific progress we have continued to make over the past 10 months. We continue to be highly encouraged by what we're seeing and we aim to develop Varseta-M aggressively for the benefit of patients with CRC and over time, many other cancers. In this presentation, we aim to address key questions that relate to the next steps in the development of Varseta, specifically the drug's efficacy profile across a larger patient data set, improving our understanding and management of gastrointestinal adverse events and how we are integrating all of this data into future dose selection as we lock in on plans for late-stage development and registration. Okay, let's get to it. Colorectal cancer remains one of the biggest unmet needs in oncology. 1.9 million patients per year are diagnosed around the world, and that's predicted to grow to more than 3 million patients by 2040. CRC is the second leading cause of cancer deaths worldwide and is growing in incidence in younger patients. 5-year survival in patients with metastatic CRC is a dismal 13%. We see colorectal cancer as one of the largest untapped solid tumor markets. This cancer type has been largely bypassed by the last 20 years of oncology innovation and progress. Antibody drug conjugates have transformed the treatment of many tumors initially hematologic cancers but increasingly solid tumors. We're seeing ADCs coming earlier in the treatment paradigm, increasingly showing opportunities to replace systemic chemotherapy in a variety of tumor types. There is no approved ADC for the treatment of CRC. Varseta-M is bringing the potential and the power of antibody drug conjugates to colorectal cancer. CRC is a very large market opportunity. In the third line setting alone there are projected to be 45,000 addressable patients in the U.S. by 2040, creating a multibillion-dollar potential market opportunity. And while the unmet need is greatest in the later line setting, the entire treatment paradigm for this cancer could be changed by a pan-CRC ADC with the potential to move to earlier lines of therapy like Varseta-M. The current standard of care in late-line metastatic CRC is highly inadequate. The options available today for patients result in objective response rates in the low single digits and progression-free survival of 2 to 5 months. These agents are unfortunately the best that are currently available for the treatment of patients after they have exhausted chemotherapy-based regimens. We must do better, and I'm pleased to say we are doing better by bringing CytomX' innovation to bear on this problem. Varseta-M was intentionally designed to be active in CRC. We carefully selected the right target and the right payload, and we have uniquely unlocked this opportunity with our PROBODY therapeutic platform. Varseta-M targets EpCAM, epithelial cell adhesion molecule. It's been known a long time that EpCAM is present at very high levels on colorectal cancer. In fact, it was first identified as a CRC marker. EpCAM is uniformly and highly expressed across all stages of the disease. There have been many efforts to target EpCAM previously. The major challenge has been it is present on most normal epithelial structures. So approaches to target EpCAM in the past have hit significant toxicity roadblocks very early in their development because of EpCAM expression in normal tissues. Based on these prior unsuccessful efforts and as also shown by our own preclinical experiments, a conventional ADC targeting EpCAM would not be expected to be developable. Varseta-M is designed to unlock EpCAM as an ADC target and is based on a high affinity anti-EpCAM antibody which we have masked using CytomX' protease-dependent peptide masking PROBODY strategy designed to minimize binding in normal tissues. The mask is removed by proteases within the tumor microenvironment allowing binding and engagement with the target and delivery of the effective mechanism and anticancer activity. The antitumor effector in Varseta-M is a novel topoisomerase-1 payload called CAMP59 that we licensed from ImmunoGen. The linker is also novel, a trialanine-cleavable peptide linker optimized for bystander effect. We now refer to this TAL CAMP59 linker payload as masetecan. Varseta-M has a drug antibody ratio of 8. We really believe with this drug candidate, we have the right target and the right payload with this overall strategy being uniquely enabled by the CytomX PROBODY platform. So where are we with the Phase I study? Shown here is the current enrollment status. As we reported in August last year, enrollment into the dose escalation and expansion phase at that time had reached a total of 73 patients. This included 60 patients treated at the prioritized expansion doses of 7.2, 8.6 and 10 milligrams per kilogram administered every 3 weeks. The updated efficacy data we're sharing today is focused on these expansion cohorts for which we now have meaningful follow-up and from which we expect our go-forward dose for the first registrational study will be selected. In Q4 last year, we increased enrollment into the Phase I study with the goal of further dose optimization. As of a data cutoff of January 16, 2026, enrollment across the study had reached 93 patients. The additional 20 patients enrolled at the first 20 of a target of 40 patients being enrolled in dose optimization cohorts. Dose optimization is focused on the top 2 doses from the expansions, 8.6 and 10 mg per kg and encompasses adjusted ideal body-weight dosing and an updated prophylaxis strategy that Wayne will walk you through shortly. Today, we'll share safety data across the full 93 patients, showing the progress we're making in adverse event management and specifically the management of treatment-related diarrhea for which we believe we are making excellent progress. We are very excited today to share updated results from the ongoing Phase I study of Varseta-M in late-line CRC. This drug candidate continues to perform extraordinarily well. Antitumor activity continues to be very strong with a 32% confirmed overall response rate at 10 mg per kg and a 20% confirmed overall response rate at 8.6 mg per kg. Our current estimate of preliminary progression-free survival has improved from 5.8 months in May of 2025 to 6.8 to 7.1 months. We've also made excellent progress in understanding and managing the safety profile of Varseta-M. We continue to see no evidence of the classic EpCAM toxicities that have limited previous efforts to drug this target and importantly, through the use of further updated prophylactic strategies, we can report today a rate of grade 3 diarrhea of 10% in early dose optimization cohorts. Simply put, we believe we have an important potential new treatment for colorectal cancer that has been uniquely enabled by our core platform technology. This is a major landmark for our company and most importantly, of course, a big step forward for patients. Our top company priority is now to move Varseta forward aggressively into its first registrational study. And with that, let me hand over to Wayne to talk you through the details of the data. Yu-Waye Chu: Thanks, Sean. Going into the data from the ongoing Phase I trial. This slide summarizes key baseline characteristics among all 93 patients who are enrolled in the dose escalation expansion and dose optimization cohorts. Consistent with what was previously reported, the study population continues to be representative of a late-line metastatic CRC population, highlighted by the fact that most patients received at least 3 prior lines of anti-cancer therapy, almost half received at least 4 lines of prior therapy and over a quarter received prior bevacizumab plus Lonsurf. 3/4 of patients had liver metastases at baseline and the majority of patients had KRAS-mutated tumors. Finally, most patients' tumors were microsatellite stable with only one patient with known MSI high disease. The following slides describe efficacy from the 60 patients treated in dose escalation and dose expansion cohorts at Varseta-M doses between 7.2 and 10 mg per kg administered on an every 3-week schedule. In the updated waterfall plot, Varseta-M continues to show striking antitumor activity and disease control across the 3 dose levels, highlighted by tumor reductions, including confirmed objective responses per RECIST 1.1 criteria. Objective responses were higher at the 8.6 and 10 mg per kg dose level with confirmed objective responses observed in 20% and 32% of patients, respectively. The arrowheads indicate patients who were still on study treatment at the time of the data cut. And at the bottom of the slide is patient-level information with respect to key baseline characteristics. As you can see, antitumor activity was observed in patients with KRAS-mutated or KRAS wild-type tumors and in patients with or without liver metastases. Finally, consistent with what was previously reported, EpCAM expression as assessed by immunohistochemistry on baseline tumor biopsies remains uniformly high with an H-score of 300 being the maximum value. All evaluable tumors had IHC H scores greater than 200 with the vast majority having H score of at least 250. This is the updated Spider plot characterizing changes in tumor burden over time. As previously reported and further substantiated with a longer median follow-up time of over 8 months, Varseta-M continues to provide impressive durable disease control. A total of 16 patients were continuing Varseta-M treatment at the time of the data cutoff, with several patients having ongoing treatment in excess of 11 months. With the observed durable objective responses and disease control, we continue to observe progression-free survival at all 3 dose levels that compare very favorably with those of currently approved therapies in late-line CRC. Notably, the median PFS of Varseta-M treatment was 7.1 months at the 10 mg per kg dose level and 6.8 months at the 8.6 mg per kg dose level. Given the follow-up time and the proportion of patients who were censored at the time of the data cut, the PFS estimates will continue to mature with the potential for further improvement. Furthermore, the PFS estimates shown here are in the absence of dose optimization which, as we will now show, has the potential to improve the safety and tolerability of Varseta-M. Turning our attention to safety, to contextualize the safety data that will be presented in the upcoming slides, I wanted to summarize some of the key observations and learnings from the Phase I dose escalation, expansion and dose-optimization cohorts as the basis for late-phase dose selection. Key early observations during dose escalation indicated a manageable safety profile with Varseta-M in that no dose-limiting toxicities were observed. Importantly, dose-limiting toxicities observed with other EpCAM directed therapies, such as pancreatitis and severe liver toxicities were not observed with Varseta-M. Also of note, interstitial lung disease, which has been observed with other TOPO I ADCs was not observed with Varseta-M. In addition, rates of hematologic toxicity were relatively low. Finally, consistent with the mechanism of action of topoisomerase-1 inhibitors, diarrhea was the most frequently observed treatment-related adverse event and early on was identified as the main adverse event of interest. As we conducted dose expansion across the 3 dose levels from 7.2 to 10 mg per kg, the overall safety profile was consistent with what was observed during dose escalation in that no new safety signals were identified. We focused on understanding key drivers of treatment-related diarrhea and gaining important experience with diarrhea mitigation strategies, particularly with respect to grade 3 diarrhea as the highest grade observed to date. Initially, a strategy of recommending loperamide prophylaxis for patients at high risk of developing diarrhea was introduced. For reasons related to physician practice patterns, patient preferences and the rapidity of enrollment into dose expansion, loperamide prophylaxis was not utilized extensively in the initial expansion phase. We nevertheless gained important insights regarding loperamide pretreatment to reduce rates of severe diarrhea. We also gained valuable experience with the oral corticosteroid budesonide as an additional approach to managed diarrhea, where 12 of 14 patients who had grade 2 or grade 3 diarrhea experienced at least a 1 grade reduction in severity after budesonide was started. Finally, a thorough analysis of Varseta-M pharmacokinetic and exposure response supported dosing based on adjusted ideal body weight to reduce inter-patient variability. The observations and learnings across dose escalation and dose expansion have been incorporated in the ongoing enrollment of patients into dose-optimization cohorts where Varseta-M is administered at 8.6 or 10 mg per kg based on adjusted ideal body weight and mandatory dual prophylaxis with loperamide and budesonide for all patients regardless of pre-existing risk factors has been implemented, as we will now show early safety data from the dose optimization cohorts indicate meaningful reductions in severe diarrhea. From the dose escalation and expansion cohorts, we observed that treatment-related adverse events occurred early during Varseta-M treatment, exemplified by the observed median time to onset of grade 3 diarrhea of approximately 5 weeks. The tornado plot shows treatment-related adverse events in the first 2 months of Varseta-M treatment at the 8.6 and 10 mg per kg dose levels, comparing the 42 patients treated in dose escalation and expansion cohorts on the left with patients treated in dose optimization cohorts on the right. Patients with at least 2 months of on-treatment follow-up were included in this analysis. This ensures equal comparison between the two groups based on an identical follow-up observational period and is representative of the overall toxicity profile, reflecting the relatively early onset of treatment-related adverse events. Treatment-related adverse events within the first 2 months of Varseta-M treatment among patients enrolled in dose escalation and expansion is highlighted by grade 3 diarrhea, which was observed in 29% of patients. In contrast, among patients enrolled into dose optimization cohorts, grade 3 diarrhea was observed in only 2 of the 20 or 10% of treated patients. Notably, the decreased incidence of grade 3 diarrhea with dose optimization is paralleled by a similar reduction in the incidence of grade 3 hypokalemia, which is a known consequence of fluid and electrolyte imbalances caused by diarrhea. So overall, while early, the data to date indicate that dose optimization may lead to an improved overall safety profile highlighted by reductions in the incidence of grade 3 diarrhea and grade 3 hypokalemia. Taking a step back from comparisons of the adverse event profiles between the dose escalation and expansion and dose optimization cohorts, the overall treatment-related adverse event profile across all cohorts and dose levels is summarized in this table. These data are consistent with the safety profile that was described previously and only partially reflects the safety profile with ongoing dose optimization. Across the safety data from these cohorts, dose escalation, expansion and dose optimization, treatment discontinuations for related adverse events were low at 11%. With additional patient enrollment and longer follow-up, we are optimistic that measures incorporated into dose optimization will result in a more favorable Varseta-M safety and tolerability profile, maximizing clinical benefit for patients. Updated pharmacokinetic data of Varseta-M is summarized here. The data are from the 73 patients treated in dose escalation and expansion cohorts and does not include data from the dose optimization cohorts where Varseta-M was dosed based on adjusted ideal body weight. The data continues to support key characteristics from earlier observations and that, as shown in the figure, PK is dose proportional. We also observed interpatient variability, which we aim to reduce with adjusted ideal body-weight based dosing. Varseta-M circulates primarily in the masked form. The mean Varseta-M half-life of 6 to 8 days is consistent with that of other in-class antibody drug conjugates, and unconjugated CAMP59 concentrations in circulation are low, constituting approximately 1% to 3% of total Varseta-M. Turning our attention to efficacy, the potential impact of Varseta-M dosing with adjusted ideal body weight on efficacy is illustrated in this figure, which shows the relationship between Varseta-M exposure and efficacy as measured by the clinically relevant metric of landmark 6-month progression-free survival. The modeled exposure response relationship based on clinical and PK data from dose escalation and dose expansion encompasses the exposure range for the 8.6 to 10 mg per kg dose levels. Notably, observed Varseta-M concentrations at 8.6 and 10 mg per kg with adjusted ideal body weight dosing fall within this exposure range, indicating that doses tested in the dose optimization cohorts are predicted to deliver similar efficacy to the corresponding nonoptimized dose levels where median PFS, as described earlier, has been shown to exceed 6 months. As you can see, as we gain an even deeper understanding of Varseta-M efficacy and safety, this model gives us confidence in the range of dose levels as we work towards discussions with FDA on dose selection based on project Optimus principles, and finalizing registrational study plans. It has been a pleasure sharing this data with you today. And with that, I turn it back to Sean for concluding remarks. Sean McCarthy: Thanks, Wayne. We're super excited about our continued progress with Varseta-M. This drug candidate is working exactly as designed, and we believe we can make an enormous difference for many, many cancer patients. This is the first and only antibody drug conjugate targeting EpCAM, a target that many have tried to drug before and failed. Our data is truly a validation of our technology and the direct embodiment of our company vision statement of transforming lives with safer, more effective therapies. To restate, we believe we have an important potential new treatment for CRC, and this is just the start. We see Varseta as a company-building asset, a pipeline and a product, if you like, that puts CytomX on a value creation trajectory that we believe can be steep and sustained. We see three major layers of value creation being unlocked in the near, medium and longer term. Firstly, we aim to rapidly bring this drug to its first approval in late-line CRC, where there are projected to be more than 45,000 addressable patients by 2040. This alone is a potential multibillion-dollar opportunity in the U.S. Secondly, we aim to bring Varseta into earlier line CRC. In fact, this has always been the vision for this program to potentially replace irinotecan. As we learn more about the overall profile of Varseta, particularly the safety profile, we are feeling increasingly confident that we can penetrate into this very large market. Our third layer of value creation is to expand into other EpCAM positive tumors of which there are many. Given that we've broken through in CRC, we believe we've done the hardest experiment first. CRC is a very difficult-to-treat cancer, and we're really excited to see what Varseta-M can do in other tumor types. In the long term, it's not a stretch to envisage Varseta advancing towards a pan-tumor histology agnostic label like Enhertu has for HER2. Moving now to our upcoming milestones. With this updated data, we do believe we have put Varseta and CytomX on a very clear path to value creation through sustained execution. I hope you all see today's update as a highly meaningful step along the way in the development of this exciting drug. There's much opportunity and a lot of work ahead of us. Our top priority right now is the rapid advancement into registrational studies to start in the first half of 2027. We look forward to sharing additional data from the Phase I study, including the dose optimization cohorts and registrational study design in the second half of 2026. The strength of our data brings into sharper focus the opportunity to conduct our first registrational study in the third line. We'll be continuing to assess this opportunity as our data matures. In terms of our earlier CRC strategy, we've already initiated Phase I assessment of Varseta in combination with bevacizumab, and we anticipate initial data late this year or early in 2027. Furthermore, today, we're also announcing our intention to start combination work with bevacizumab plus chemo by the end of the year. The team is also working very hard to start our first clinical study outside of CRC later this year as well. So really exciting times for CytomX. Thank you all for joining today, and before opening up the call for questions, I really want to thank the CytomX team for doing just such an incredible job. Varseta has been a long time in the making, and it takes so much dedication and perseverance to do this important work. My colleagues and I thank the patients who have trusted us and participated in this Phase I clinical study, and we sincerely thank our investigators for their thoughtful guidance and diligent leadership. At CytomX, we've never been more excited about what we're doing for patients and we look forward to providing future updates. And with that, let's open up the call for questions. Operator: [Operator Instructions] Our first question comes from the line of Edward Tenthoff with Piper Sandler. Edward Tenthoff: Congratulations. Very impressed by these continued response rates and PFS from Varseta. Really, really cool, and I appreciate all the detail in both the dosing data and also the plans going forward. I guess when it comes to the pivotal trial, appreciating that you'll share design in the second half, how large are you anticipating from this study? And then secondly, could you share any color in terms of what might be leading indications beyond CRC for the next EpCAM positive tumor? Sean McCarthy: Great. Thanks, Ted, for the questions. With regards to the pivotal study or the first pivotal study, still work in progress, of course, in thinking about sizing. We're obviously super encouraged and excited by the level of activity that Varseta is bringing in, in late-line CRC. And I want to emphasize, actually, this is -- continues to be a very late-line patient population, as you can see from the demographics that Wayne highlighted. We do see that with the -- with this updated data set, as I mentioned, and the PFS in particular, continuing to improve, we do feel increasingly excited about the pivotal being in the third line. We, of course, need to learn about OS and we'll be sharing OS data as the program matures. That will be a key determiner of our decision-making on the pivotal design. But too early to say what the size of that study would be, but we think it would be a manageable size and executed, we think, very quickly. Chris Ogden: And do you want to comment on potential other indications outside of CRC? Sean McCarthy: Yes. With regard to your second question, Ted, on non-CRC, as we've said for some time, we really are -- we're really excited about the broader potential of EpCAM. It's expressed in many, if not all, of the solid tumors. We highlight in our presentation, have for some time, other GI tumors including gastric and pancreatic. Of course, it's highly expressed in lung cancer, ovarian cancer, certain breast cancers. And so there's a wide range of opportunities here that we continue to work through. To this point, as you'll understand, we've been highly focused in CRC on bringing this drug to its first pivotal study, but we're excited to move into other tumor types by the end of this year. Operator: Our next question comes from the line of Roger Song with Jefferies. Jiale Song: Huge congrats for the data, very impressive on the efficacy and the tolerability side. Maybe, Sean, so for the initial dose expansion, this diarrhea kind of prophylactic protocol you say on the call, it was not fully implemented or widely used and then now using the dual. So how should we think about the implementation here and then also the real-world use? What is your advice, feedback on this potential regimen for future? And then in terms of the pivotal also a quick follow-up on that is, can you comment on this, you say, the third line and then still looking at the OS, how likely this PFS will be the sole primary endpoint given the data is very impressive here compared to the standard of care? Sean McCarthy: Thanks, Roger. Great questions. So yes, with regard to the expansion phase, one of the things that we've commented on quite frequently over the last 6 or so months is just how rapidly the expansion is enrolled. The demand for the drug, as I think you can now see, based on this -- what it's doing. The demand for the drug was very high. We enrolled the expansions faster than anticipated. And so that and another reason, the implementation of the original loperamide prophylaxis was not as extensive as we had perhaps anticipated. But there's also a clinical reason for that as well, which is these patients, particularly in the very late line, of course, they've experienced GI adverse events at various points in their treatment journey. They all have, for the most part, experience with loperamide. And it's a drug that, while bringing benefit, of course, to the treatment of diarrhea, it comes with its own challenges as well. So patients, they, in some cases, are going to make their own choices about how they manage that particular drug, unless it's really impressed upon them to use it. I would contrast that a little bit to the budesonide, which we've really demonstrate some key learnings in the expansion phase that budesonide is looking to be effective as well. And this is a drug that is -- we've experienced that patients are very compliant with. So in terms of the prophylaxis overall, its use in the real world, we feel really good that it will be adhered to as we continue to refine and update and learn what -- how to optimize the overall protocol. In terms of progression-free survival being a primary endpoint, we -- we're not guiding to that. There's no real precedent for that in the late-line CRC setting. We are planning for OS to be the primary. That is something we'll continue to talk to FDA about. And of course, we are looking at all and any ways to accelerate the development of Varseta-M, but for the time being, our assumption continues to be unchanged. The first pivotal would be principally based on an OS primary but given the unprecedented level of activity of this drug, we'll continue to look at all and any options. Operator: Our next question comes from the line of Matthew Biegler with OpCo. Matthew Biegler: Congrats from us as well. Could you comment on positioning relative to the other ADCs in development like Precem-TcT, especially now with diarrheal prophylaxis seeming to work well? Kind of what are like the puts and takes from a physician's perspective in choosing one of the ADCs over the other? Sean McCarthy: Yes. Thanks, Matt. Really terrific question on the broader landscape. And as we've been saying, and this is just so exciting for patients, the ADCs are coming to colorectal cancer. And we think we've got a really good one, if not potentially the best. So I want to emphasize again that Varseta is a first-in-class anti-EpCAM ADC. It may very well be the best-in-class ADC for CRC based on this data that we're sharing today. This is a highly competitive data set, we believe, a highly competitive drug. And I think of particular importance as you mentioned, the safety profile that we continue to understand and learn how to manage, this is really important because it continues to open up, we think the movement of Varseta into earlier lines of treatment into the first and second-line setting based on its, we think, potential combinability and effective combinability with the other components of frontline treatment. So this is a very important data set that we're showing today with big implications to where this drug can go. And as I said, we will continue to develop the drug aggressively and position -- we think we've got a very competitive position against, for example, the AbbVie and Merck KGaA drugs. Operator: Our next question comes from the line of Michael Schmidt with Guggenheim. Michael Schmidt: Congrats on the data from us as well. Obviously, the efficacy looks very compelling despite the fact that you have a very high proportion of patients that are 4 prior lines, the fifth line plus population. And I'm just curious if you've looked at the data in third-line-only patients. Just curious if you see even further improved activity and something that could look closer to what you've been rolling in Phase III? And then a question on diarrhea. Just curious if you could just help us understand a bit more the duration of diarrhea? For example, is this a first dose effect or something that patients are having for a longer period of time? And obviously, PFS already looks very good despite the diarrhea. And I'm just curious when you think about the adjusted ideal body weight dosing cohorts, which is something that's not uncommon for ADCs in general, just curious if there's an opportunity to further improve efficacy with that dose optimization that's ongoing? Sean McCarthy: Thanks, Michael. A series of wonderful questions there. So I appreciate that. So first of all, in terms of parsing out the patient population in the data set, I guess this is -- just continues to be a late-line patient population that we think showing this level of activity is a great place to start. And so we're obviously very optimistic that as we move the drug earlier, the drug will continue to show similar, if not even more impressive activity. And we're not dissecting the data set really any more than that at this moment in time. We think it really speaks for itself. In terms of duration of diarrhea, I mean we've been very focused on time to onset, as Wayne mentioned, about 5 weeks is the median time to onset for grade 3 when we see it. We're now in this position with this updated prophylaxis strategy to really get on top of that and get that number down, as you've seen in this preliminary data from dose optimization Patients treated with this prophylactic regimen, obviously, you're seeing a much reduced incidence of grade 3. So that's really what we're focused on. In the earlier experience in the expansion phase, we found that patients are responsive to the treatment with budesonide. And as Wayne pointed out, we saw 12 of 14 patients treated who we followed closely in the earlier stage of the study show at least 1 grade improvement in their diarrhea, giving us that initial clue that budesonide could be a terrific addition to the prophylactic strategy. You make another really important point, Michael, on PFS. These PFS numbers are from the expansion phase and the expansion phase did not have optimized prophylaxis. So we do feel that this data can continue to improve. We do feel that this drug can continue to outperform over time as we learn more about it. And that also relates to your last question on adjusted ideal body weight dosing, which, as you correctly point out, is something that has been used for a number of ADCs and shown to be effective. It's really aimed at decreasing the outliers, compressing the dose range so that we have more consistent dosing, and that should, we think, just add to our ability to manage the safety profile, keep patients on drug for the maximum period of time, maximizing the duration of their clinical benefit. Operator: Our next question comes from the line of Olivia Brayer with Cantor Fitzgerald. Olivia Brayer: My congratulations as well on today's data. Sean, I know you aren't necessarily breaking things out yet by individual treatment line, but anything you can tell us about how many lines of therapy the confirmed partial responses that you had in that 8.6 and 10 mg per kg cohorts? And then I wanted to ask a follow-up on your pivotal design. Any sense yet for what the comparator arm would need to be given that you guys are planning on going straight into the third line setting? And then just kind of a final question. I also wanted to ask about your plan for implementing a prophylaxis protocol as you think about a combination approach and moving this program into earlier treatment lines? Sean McCarthy: Thanks, Olivia. Great questions. In terms of treatment line, I think we just emphasized that, again, late line patient population, we haven't broken that out. But I would say that across the study, it's very consistent with what we saw in the Phase I disclosure in May of last year, where we did break out at that time the specific number of priors for each patient. And you could see one patient, we do like to point out, who had actually 10 prior lines of therapy, who had actually the deepest response. So this drug is active in patients who are heavily pretreated really across the board. I should also emphasize something we haven't really focused on too much today, I can't underscore how important this is, but this is an unselected patient population. So we're not selecting for EpCAM. We're not selecting for target. It really is an all-comer late-stage patient population. This is incredibly valuable and attractive in the context of the use of this drug, ultimately, we think, in its uptake because patients can be rapidly brought on to Varseta-M without a whole lot of workup necessary because we're not selecting for KRAS or BRAF or liver mets. And you could see actually the percentage of patients in the study with liver mets and KRAS mutations is higher than it was last year. It's almost -- it's about 3/4 of patients. I think this gives some important insights into how oncologists are using this drug at this early stage in its development. In terms of the pivotal comparator, I mean, in the third line, if you look at studies being conducted by others, that's bevacizumab plus Lonsurf that is currently the standard of care in the third-line setting, so that's something that we'll look at. As we've said, we do believe this data points in that -- it points us increasingly in that direction. No decisions made yet, but we are actively considering that as the data continues to mature, and in particular, as we get a read on OS later in the year. And then in terms of prophylactic strategies, let me ask Wayne to comment on that in terms of the extrapolation of what we've seen so far into the combination setting. Yu-Waye Chu: Yes. So I mean as we highlighted today, I mean we really believe that we have a very effective prophylactic strategy with the dual use of low loperamide and budesonide. And we don't foresee significant challenges to move into the front line simply for multiple reasons. One, we should remind everyone that both medications are oral. So there's a convenience factor for patients that make this relatively easy to take. Secondly, even in the early line setting, remember that many of the chemotherapy agents used in early line settings themselves cause diarrhea. So management of diarrhea with the standard agents will formally involve some form of anti-GI-motility agents such as loperamide. So the adaptation of loperamide in the prophylactic sense in the early line should not be a significant barrier. Finally, I'll just point out that the use of combination prophylactic agents, it's not just restricted to diarrhea. For example -- nausea and vomiting, for example, typically utilize multiple agents for prophylaxis, including that, that's administered intravenously. So we don't -- so again, I think in total, we don't see this as a significant barrier in any way of implementing prophylaxis in early line settings. Operator: Our next question comes from the line of Etzer Darout with Barclays. Etzer Darout: Congrats as well on this data update. A couple of questions for me. First, just curious about maybe dose selection for the bev combination studies as well as the other tumor types based on the data we're seeing today. And also, the KRAS activity was interesting. Just wondering if you would consider KRAS wild-type as well as mutant in an earlier line setting based again on the data that you're disclosing today? Sean McCarthy: Thanks, Etzer. With regard to -- great questions. With regard to dose selection for the bev combo in other tumors, work in progress. So we are doing some dose ranging with bev as you might imagine, that work has been kicked off, and we'll have more to say about that later this year or early next year. I should also say that in thinking about dose optimization overall, just thinking about where we are now compared to where we were 10 or so months ago, we've narrowed the field from 3 active doses 7.2, 8.6 and 10, so the two highest doses, 8.6 and 10. And these are both great options, and we're learning more about them to pick the go-forward dose with the first pivotal. So we've really learned an enormous amount about how to use this drug and how to optimize dosing in a very short space of time. And we'll be porting that, of course, over to our experience as we begin work in other tumor types as well. So terrific progress. In terms of KRAS mutational status, that's an interesting question because, of course, in the context of EGFR therapies, there is patient selection that relates to the signaling mechanism of the EGF receptor and RAS signaling and such like. In our case, this is one of the beauties of Varseta, it doesn't really matter. We don't think the target is present at high levels on every patient. And we've shown activity in KRAS wild type and KRAS mutant. So I think it just emphasizes that we -- right now, we don't need to select patients. Now that doesn't mean that we're not looking at our data for clues as to where the drug may be perhaps even more active. But right now, the main message with Varseta is that this is a drug for all-comer CRC. Operator: Our next question comes from the line of Anupam Rama with JPMorgan. Anupam Rama: Congrats on the update. Sean, just wanted to follow up on your comments about, hey, we're learning a lot more here about the 8.6 and 10 mg doses that were used in the dose optimization. So any difference there? I know it's only 20 patients, but any difference there in terms of what you're seeing on diarrhea as well as on the efficacy side, ORR in particular? Anything in the dose optimization portion that you can comment on in the 20 or so patients? Sean McCarthy: Yes, thanks, Anupam. With regards to the diarrhea, too early to comment on that. And obviously, the data as it stands, we think is very exciting, but it is early and the dose optimization cohort as we enroll up to the full 40 patients will continue to mature over time. So with regard to activity, the exposure efficacy model that Wayne walked you through is, we think, really important and it integrates so much of the work that we've done over the last year or so in understanding the pharmacokinetic and pharmacodynamic profile of Varseta, and we feel very optimistic that we're in the right dose range with adjusted ideal body-weight dosing. So the drug will continue to show robust activity as we move forward. So that data will be forthcoming. But what we've really tried to convey with that model that's based on data from the expansion cohorts itself. This is really important. The PK exposure efficacy model is built on our actual experience in the expansion phase. We think it's highly predictive of what we'll see with the optimization cohorts. And that data, as Wayne also mentioned, will be very helpful as we go to FDA and discuss considerations around project Optimus. Operator: Our next question comes from the line of Robert Driscoll with Wedbush. Robert Driscoll: Congrats again on the data update today. Just kind of given the reduction in GI AEs here with a prophylaxis regimen, and a lot of things kind of in the optimized dosing. Just wondered if you're considering reevaluating the higher dose cohorts here, the 11 or 12? And then second question, just -- could you just remind us of the focused indications here for the broadening study for EpCAM positive tumor types and how big those cohorts might be? Sean McCarthy: Thanks, Robert. So with regard to the question on reducing tox and increasing dose, we're very pleased with where we are right now with these 2 doses. We think they integrate really all of the learning so far. They continue to give us a lot of room to maneuver, as we've always said with Varseta. And so we don't really see a need to push the dose higher. Now that said, this drug is going to have a long life cycle ahead of it. So there's a lot of work that remains to be done to maximize that opportunity. But right now, we feel really good about where we are. In terms of non-CRC, again, there are so many opportunities there. It is so exciting to think about how many patients we could benefit with this drug over time. And nothing really more to say there in terms of exactly where we're going or size of study, but we will provide additional details as the year goes on. It is important to strike a balance. And it's one of the hardest things to do really at the moment. It's striking the balance between going as fast as we can in CRC and getting going elsewhere, but we're going to try and do it all. Operator: [Operator Instructions] Our next question comes from the line of Mitchell Kapoor with H.C. Wainwright. Mitchell Kapoor: Congrats on the impressive data. A couple of questions from us. Firstly, can you comment on the frequency of grade 3 diarrhea events at the 8.6 and 10 mg per kg dose levels? Our work with KOLs was suggesting that the number of events was maybe more important than the headline of the rates of grade 3 diarrhea. And then separately, on the optimized safety regimen, how much of the grade 3 diarrhea improvement to 10% do you attribute to the adjusted body weight dosing versus the updated prophylaxis? And then if you can just help us on the median time on therapy for these optimized safety cohort patients just in light of the median time to onset of the diarrhea events? Chris Ogden: Mitch, this is Chris. I think your first question relates to does grade 3 diarrhea tend to recur, is that my understanding of the question versus just... Mitchell Kapoor: Yes, right. Like are there patients in the hospital once a month or kind of like how does the grade 3 diarrhea manifest itself over time? Sean McCarthy: Yes. So the -- our focus -- Mitch, it's a good question. Our focus is in these optimization cohorts, of course, is to prevent patients getting into it in the first place. And that's really what we're focused on right now. So -- and we're just really encouraged by these initial data. And again, I'd like to really emphasize and really commend Wayne and the team for doing some terrific work here, really listening to our investigators, really understanding the patient experience and keying into some of these key clinical observations, particularly with budesonide and seeing that evidence that given some of these PK outliers that AIBW dosing could be a significant addition to the overall dosing strategy. So in terms of -- on that note, in terms of the role or the contribution of adjusted ideal body weight to the improved safety profile, hard to tell, obviously, right now, we're using loperamide, budesonide and AIBW. And it looks like it's working. So we'll take it. And I think over time, we'll learn more. But it would be expected I guess, said slightly differently, it wouldn't be a surprise, of course, if AIBW was having a significant impact because we did see -- as you can see in the PK curves, we wanted to be very transparent about this and show the per patient PK. You can see that in the non-AIBW, there is a fair amount of variability, some of which is driven by BMI, for example. So we'll learn more over time. And I'm sorry, I think your last question... Mitchell Kapoor: Yes. The last part of it was just trying to understand how long these patients have been on therapy on the optimized safety dose just in light of the median time to onset of diarrhea, so we can understand kind of the context of that 10%, right? Sean McCarthy: Yes. So as we presented in today's update, this is the 2-month cutoff, and that's very relevant because the median time to onset of grade 3 in our experience to date is about 5 weeks. So we do think this is a meaningful time point and we will continue to follow these patients. And we're continuing to enroll, right? We're going to increase enrollment from 20 to 40 patients. This will be a much more mature data set as we move into midyear and into the second half of 2026. So work in progress, but we think a very good start. Operator: That concludes our question-and-answer session. I will now turn the call back over to Dr. Sean McCarthy for closing remarks. Sean McCarthy: Well, thank you again, everyone, for joining us today. We are delighted to have given this update and we appreciate your interest, and we very much look forward to providing additional updates as the year goes on and following up with you all. Take care. Operator: This concludes today's conference. Thank you for your participation. You may now disconnect. Before you buy stock in CytomX Therapeutics, consider this: The Motley Fool Stock Advisor analyst team just identified what they believe are the 10 best stocks for investors to buy now… and CytomX Therapeutics wasn’t one of them. The 10 stocks that made the cut are built for long-term growth and could produce monster returns in the coming years. Consider when Netflix made this list on December 17, 2004... if you invested $1,000 at the time of our recommendation, you’d have $462,983!* Or when Nvidia made this list on April 15, 2005... if you invested $1,000 at the time of our recommendation, you’d have $1,375,447!* That performance is why people listen. 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CytomX (CTMX) Q4 2025 Earnings Transcript was originally published by The Motley Fool

CytomX Therapeutics, Inc. (NASDAQ:CTMX) investors will be delighted, with the company turning in some strong numbers with its latest results. The results were impressive, with revenues of US$10m exceeding analyst forecasts by 119%, and statutory losses of US$0.10 were likewise much smaller than the analysts had forecast. The analysts typically update their forecasts at each earnings report, and we can judge from their estimates whether their view of the company has changed or if there are any new concerns to be aware of. With this in mind, we've gathered the latest statutory forecasts to see what the analysts are expecting for next year. AI is about to change healthcare. These 20 stocks are working on everything from early diagnostics to drug discovery. The best part - they are all under $10bn in marketcap - there is still time to get in early. Following the recent earnings report, the consensus from seven analysts covering CytomX Therapeutics is for revenues of US$33.1m in 2026. This implies a perceptible 6.8% decline in revenue compared to the last 12 months. Per-share losses are expected to explode, reaching US$0.48 per share. Yet prior to the latest earnings, the analysts had been forecasting revenues of US$22.2m and losses of US$0.49 per share in 2026. So there's definitely been a change in sentiment in this update, with the analysts upgrading this year's revenue estimates, while at the same time holding losses per share steady. View our latest analysis for CytomX Therapeutics The analysts increased their price target 52% to US$13.67, perhaps signalling that higher revenues are a strong leading indicator for CytomX Therapeutics's valuation. There's another way to think about price targets though, and that's to look at the range of price targets put forward by analysts, because a wide range of estimates could suggest a diverse view on possible outcomes for the business. The most optimistic CytomX Therapeutics analyst has a price target of US$17.00 per share, while the most pessimistic values it at US$11.00. As you can see, analysts are not all in agreement on the stock's future, but the range of estimates is still reasonably narrow, which could suggest that the outcome is not totally unpredictable. Of course, another way to look at these forecasts is to place them into context against the industry itself. These estimates imply that revenue is expected to slow, with a forecast annualised decline of 9.0% by the end of 2026. This indicates a significant reduction from annual growth of 18% over the last five years. Compare this with our data, which suggests that other companies in the same industry are, in aggregate, expected to see their revenue grow 22% per year. So although its revenues are forecast to shrink, this cloud does not come with a silver lining - CytomX Therapeutics is expected to lag the wider industry. The most important thing to take away is that the analysts reconfirmed their loss per share estimates for next year. They also upgraded their revenue estimates for next year, even though it is expected to grow slower than the wider industry. There was also a nice increase in the price target, with the analysts clearly feeling that the intrinsic value of the business is improving. With that in mind, we wouldn't be too quick to come to a conclusion on CytomX Therapeutics. Long-term earnings power is much more important than next year's profits. At Simply Wall St, we have a full range of analyst estimates for CytomX Therapeutics going out to 2028, and you can see them free on our platform here.. We don't want to rain on the parade too much, but we did also find 5 warning signs for CytomX Therapeutics (3 are potentially serious!) that you need to be mindful of. Have feedback on this article? Concerned about the content? Get in touch with us directly. Alternatively, email editorial-team (at) simplywallst.com. This article by Simply Wall St is general in nature. We provide commentary based on historical data and analyst forecasts only using an unbiased methodology and our articles are not intended to be financial advice. It does not constitute a recommendation to buy or sell any stock, and does not take account of your objectives, or your financial situation. We aim to bring you long-term focused analysis driven by fundamental data. Note that our analysis may not factor in the latest price-sensitive company announcements or qualitative material. Simply Wall St has no position in any stocks mentioned.

Image source: The Motley Fool. Thursday, May 7, 2026 at 5 p.m. ET Chairman & Chief Executive Officer — Sean McCarthy Chief Financial Officer — Chris Ogden Sean McCarthy: Thanks, Chris, and good afternoon, everyone. We're very pleased to be here today to provide an update on our first quarter developments and guidance for what's continuing to be a transformational year for CytomX. 2026 is off to a very exciting start, driven by our excellent clinical progress with Varseta-M in late line colorectal cancer. Varseta-M is a first-in-class EpCAM targeting antibody drug conjugate, or ADC, that was uniquely designed and enabled by our proprietary PROBODY therapeutic masking platform. Varseta-M is the only EpCAM-directed ADC in clinical development to our knowledge, affording us a strong lead and a powerful competitive advantage. EpCAM is one of the most abundant solid tumor surface antigens and CytomX's breakthrough in unlocking EpCAM as an ADC target positions Varseta-M as a company-building asset over the near and long-term. We see multiple layers of value creation potential for CytomX through the advancement of Varseta-M. In colorectal cancer, which I'll now refer to as CRC, our goal is for Varseta to become a core component of the standard of care, including in earlier line therapy. Metastatic CRC remains one of the largest areas of unmet need in oncology today, which really underscores the urgency we feel at CytomX to progress Varseta-M towards the market as rapidly as possible. Commercially, in the late line setting alone, this represents a multibillion-dollar market. In addition to the very substantial opportunity in CRC, we also plan to capitalize on our leadership in EpCAM targeting by developing Varseta-M in other cancers and ultimately as a pan-tumor therapy. Varseta has the long-term potential to positively impact the lives of so many people with cancer, and we are focused on executing with urgency to rapidly progress this potential therapy to regulatory approval. CytomX has made a very strong start in the clinic with Varseta-M. In our most recent Phase I data update in March this year, we shared updated efficacy data in late line metastatic CRC, showing a confirmed overall response rate between 20% and 32% and approximately 7 months of median progression-free survival. These data position Varseta as a potentially transformative step forward in the treatment of metastatic CRC, where currently available therapies offer overall response rates only in the low single digits and just a few months of PFS. Varseta-M is working exactly as designed, and it's unlocking the true potential of EpCAM for the first time. With Varseta, CytomX is bringing the power of the ADC class to colorectal cancer. I want to really underscore here that we've achieved something very significant with our PROBODY platform technology. In our view and based on our preclinical data and efforts of others over many years, we believe we can say with confidence that a conventional unmasked ADC targeting EpCAM would have no chance of achieving dose levels that deliver meaningful anticancer activity due to severe on-target toxicities. In contrast with Varseta-M, we have achieved remarkable anticancer activity in one of the hardest-to-treat cancer types. We firmly believe we have done the hardest experiment first by focusing initially in CRC and that the best is yet to come. In terms of key near-term objectives for Varseta-M, we are currently in dose optimization with the goal of advancing into a registrational study in late line CRC in the first half of 2027. Today, we're very pleased to share that we have completed enrollment in the ongoing dose optimization cohorts with 40 total patients now enrolled across the 8.6 and 10 milligram per kilogram doses, taking total enrollment across the Phase I study to 113 patients. We remain well on track for an update before the end of this year as we work towards prioritizing 1 of these 2 doses of this highly active drug candidate for our first pivotal study. In evaluating the potential registrational study dose, we're focused on optimizing the risk benefit of Varseta-M, building on the significant learnings in the dose escalation, expansion and optimization phases. Regarding Varseta-M safety, we have been highly encouraged by the preliminary results we shared in March from dose optimization that show that updated patient management strategies have the potential to substantially reduce the rate of high-grade diarrhea we saw earlier in Phase I development. This is the principal adverse event of interest with Varseta, and it's something we feel confident we can get an increasingly well-developed understanding of as we move forward through the optimization cohorts and beyond. Typically, patients respond very well to management and our overall discontinuation rates are low, accounting for the impressive progression-free survival data we have shared to-date. In terms of our next clinical communication, we expect to provide an overall Phase I data update, including safety and efficacy from the monotherapy dose optimization in the second half of this year. We expect these data, along with FDA interactions in 2026 to inform Varseta-M monotherapy dose selection and the first registrational study design. Our primary goal with Varseta-M is initially to develop in the late line where we see this drug candidate as highly differentiated and frankly, as offering a highly impactful new option for CRC patients. Over time, our vision for Varseta in CRC is to replace systemic irinotecan in the treatment paradigm and potentially to displace chemotherapy entirely. Accordingly, and in parallel to its development as a monotherapy in CRC, we are aggressively advancing Varseta-M into combination studies to enable earlier line utilization. Strategically, we see an enormous opportunity for Varseta in early line CRC. To access this opportunity, we have initiated a combination with bevacizumab as a first step to moving Varseta into earlier line therapy. Anti-VEGF antibodies, including bevacizumab are extensively utilized in early and late line CRC treatment. So this will be a foundational combination. Varseta-M doses assessed in combination with bevacizumab will include both every 2 weeks and every 4 weeks schedules to align dosing with the approved 5 mg per kg every 2-week schedule standardly used in the clinic today. We expect initial clinical data for this combination by the first half of 2027. We're also accelerating plans to study Varseta in combination with chemotherapy, and we plan to begin a Phase I/II chemotherapy combination study in the second half of 2026, evaluating Varseta in combination with bevacizumab by fluorouracil and leucovorin with the potential to advance into the first and second lines. In addition to our work in colorectal cancer, we are on track to begin Phase I expansion cohorts in additional EpCAM-expressing indications in the second half of 2026. We look forward to providing an update on the initial non-CRC indications later this year with the goal of generating clinical data supporting Varseta's ultimate pan-tumor potential. Turning now to CX-801, our masked interferon alpha-2b program, which is currently in Phase I development for advanced checkpoint refractory melanoma. Our vision here is for CX-801 to become a new centerpiece for combination cancer immunotherapy as we harness and redirect the power of this cytokine to reprogram and activate antitumor immunity. We initially see CX-801 as well positioned to address the high unmet need in PD-1 refractory melanoma where response rates to approved standard of care remain in the single-digit percentages with limited treatment options available or in clinical development. Interferon alpha-2b is a potent cytokine that has validated clinical activity in melanoma and other cancers and our initial translational data from Phase I suggests that CX-801's mechanism of action is working as designed in the tumor microenvironment. Importantly, our data shared at SITC in 2025 are highly supportive of our strategy for combining with the checkpoint inhibitor, KEYTRUDA. Our ongoing CX-801 Phase I monotherapy dose escalation study has advanced to the fourth dose level, which exceeds the approved clinical dose of unmasked interferon alpha-2b. CX-801 has been well tolerated to-date, suggesting that our masking strategy is broadening the therapeutic window as designed. Combination dose escalation with KEYTRUDA is also progressing very well and is now actively enrolling in the third dose level. Overall, we view CX-801 as very well positioned to address a significant unmet need in advanced melanoma, and we look forward to sharing initial clinical data by the end of this year. With that, I'll now transition back to Chris. Chris Ogden: Thank you, Sean. Reinforcing Sean's earlier sentiment, we kicked off 2026 from a position of strength, not only with Varseta-M's encouraging data, but with the financing completed in March, a strong balance sheet that enables us to continue to execute against the significant value creation potential of Varseta and the PROBODY platform. CytomX is in a strong financial position with projected cash runway to at least the second half of 2028 and the potential to achieve multiple milestones. Of note, our runway guidance does not include any supplemental milestones from existing collaborations or any new business development. Importantly, we expect our current cash position will enable us to advance Varseta-M into a registrational study in late line CRC, also deliver safety and efficacy data for Varseta-M in combination with bevacizumab as well as Varseta-M data in combination with chemotherapy and deliver initial clinical data for Varseta-M in indications beyond CRC. Based on these opportunities, which have the potential to yield significant long-term commercial potential, we expect our capital allocation to be highly focused on Varseta-M over the near to medium term. With that, I'll now walk through our first quarter financial results. As of March 31, 2026, we ended the quarter with $346.7 million in cash, cash equivalents and investments versus $137.1 million in cash as of December 31, 2025. Looking at revenue and operating expenses for the quarter, total revenue was $10.3 million compared to $50.9 million in the first quarter of 2025. The decrease in revenue was primarily attributed to the completion of obligations in 2025 under collaborations with Bristol Myers Squibb and Amgen. Operating expenses for the first quarter were $29.8 million compared to $28.3 million in the first quarter of 2025. R&D expenses were $19.2 million during the first quarter, representing an increase of $0.4 million versus the first quarter of 2025, primarily due to increased manufacturing activities for Varseta-M, partially offset by $1.8 million in restructuring expense incurred in the first quarter of 2025. G&A expenses increased by $1.1 million during the 3 months ended March 31, 2026, to $10.6 million compared to $9.4 million for the corresponding period in 2025, which included $1.1 million of one-time restructuring expenses. As we move throughout the remainder of 2026, we will continue to be disciplined in our capital allocation and advancing the highest Varseta-M priorities for patients and CytomX stakeholders. With that, I'll turn the call back to Sean for closing remarks. Sean McCarthy: Thanks, Chris, and thanks, everyone, for joining us today. We're very proud of the remarkable progress we've made with Varseta-M, and we're now in the privileged position of bringing the transformative potential of an EpCAM directed antibody drug conjugate to colorectal cancer patients. We look forward to providing additional updates as the year progresses and as the development program for Varseta-M broadens substantially. We also remain focused on the advancement of the clinical program for CX-801 with the initial goal of delivering a more effective treatment option for patients with advanced melanoma. Before I conclude today's call, I want to sincerely thank and recognize the patients who join our studies, their families, our clinical investigators and our dedicated CytomX team. With that, operator, let's go ahead and open up the call for Q&A. Operator: [Operator Instructions] And our first question will come from Paul Jeng of Guggenheim. Paul Jeng: So for Varseta-M, can you just talk a little bit about the scope of the clinical update you'll have in the second half? Will some or most of the dose optimization cohort patients have sufficient follow-up for PFS? Do you plan to break down responses by subgroup such as third line versus fourth line plus of therapy? And then how are you thinking about initial disclosures of overall survival from the study? Sean McCarthy: Yes. Thanks, Paul, for the questions. So we are expecting that the update in the second half will be fairly substantial. As we've mentioned today, we've now enrolled 113 patients across the dose escalation expansion and now optimization phases of the study. So this is a very rich data set that is emerging for our first evaluation of Varseta in CRC patients. So in terms of the update, it will be across the entire study. It will include data from the full 40 patients optimization phase. And yes, we expect to have a reasonable follow-up in terms of safety and efficacy for the optimization patients, including, I would think an initial estimate of PFS. As you'll recall, last year, our guidance as we came through the second half of 2025 was that we wanted to communicate data this year when it was mature and meaningful, and that continues to be the case and continues to be our philosophy. In terms of subgroups, yes, we'll certainly communicate the demographics of the patient population that we're enrolling. We do expect it to look quite similar to the patient population that we enrolled in the escalation and expansion phases. And I want to emphasize that one of the really differentiating and distinguishing features of Varseta-M as a drug for colorectal cancer is that we can treat every patient. We're not selecting patients. We don't need to select patients. This really is a drug for all-comer late line CRC. And we see this as potentially a huge competitive advantage as we move the drug toward the market. In terms of the third component of your question and overall survival, yes, we absolutely anticipate having or providing, if you like, a first look at OS in this update in the second half of the year. Operator: And our next question will be coming from the line of Edward Tenthoff of Piper Sandler. Edward Tenthoff: Really excited for more data looking in the back half. I just had one quick clarification question on 1-2 chemo combo. Will that be triplet? So will you have -- or I guess, quadruple with the 2 chemos? And will that include Avastin? And do you need any of the Avastin combo data to start that chemo combo trial? I just want to make sure I understand that correctly. Sean McCarthy: Ted, thanks for the question. Taking the first question first in terms of the nature of the combination, yes, we absolutely will want to evaluate the Varseta-M plus chemo plus bev combination. We will want to look at that. Right now, we don't see the data from the ongoing -- sorry, Varseta-M plus bev as gating necessarily to starting that work in the second half. We do, of course, see that bev combination work -- the Varseta-M/bev combination is going to be really important to further down the road, considering from a registrational study perspective, the design of that study, if indeed we do, at some future point, decide to compare Varseta-M plus bev against other comparator arms. But we do plan to look at that triplet in the chemo combination later this year. Edward Tenthoff: Yes. And then that's really helpful. And then when it comes to the new EpCAM positive tumors, I'm really excited to hear what you're thinking is. Maybe you can share with us now kind of what goes into some of that prioritization because there's a lot of different places you could go? Sean McCarthy: Yes, there are so many places we could go because EpCAM is such a broadly expressed cancer target on so many solid tumors. So we do have a lot of opportunities to work through and prioritize. It's not lost on us, of course, or really anybody else that there are some -- there's quite a number of, if you like, adjacent GI tumors that can make a lot of sense to evaluate with Varseta-M. There are also many others. So something that we continue to work through and prioritize, and we will communicate more specificity on exactly what we're planning to do in the second half. Operator: [Audio Gap] line of Anupam Rama of JPMorgan. Unknown Analyst: This is [ Joyce ] on for Anupam. I think previously, you had said you were targeting midyear FDA interactions to start discussing the pivotal trial design. To what extent is reaching alignment on the trial design ultimately gated on seeing your dose optimization update later this year? I think you can start having those conversations with FDA now with your initial data in hand. So just how should we think about the update later this year in terms of solidifying your registrational strategy? Sean McCarthy: Yes. Thanks. Great question. Really important question. And I'll start by saying that we're just really excited to have this dialogue with FDA as we progress through the year. We anticipate multiple interactions. And we do expect that the data from the optimization cohorts will be central to those conversations in relation to dose selection for the first pivotal study. That's, of course, a large part of the reason we're doing these additional 2n equals 20 cohorts at the 8.6 and 10 mg per kg doses is to generate data to satisfy Project Optimus and have a highly productive a conversation with FDA as we can. So yes, that data will be important, and that's why we're guiding that really towards the end of the year or by the end of the year, the next comprehensive update that we plan to provide will not only include, of course, data across the 113-patient Phase I study, but will also include guidance as to where we're going next in terms of design of the first pivotal study, what the patient population is, what the comparator arm is and of course, what the dose is. Operator: And our next question will be coming from the line of Roger Song of Jefferies. Nabeel Nissar: Congrats on the progress. This is Nabeel on for Roger. Maybe one for me first. So just on the 8.6 versus 10 mg per kg, just a little bit curious if you could maybe give some color on the dose decision logic because we saw the headline ORR of 32% versus 20%. But what is the framework that you guys would apply to finally lock in on a dose? Or is it related to tolerability at this point? Because we noticed in the exposure response model, it looks like there's pretty similar efficacy. So are you weighing depth and durability? Are you weighing safety more? Sean McCarthy: Yes. Thanks, Nabeel. That's obviously -- there's a lot in that question in terms of the work that we are doing in real time, and we'll be continuing to do as we move through the year to lock in on the go-forward dose. And first thing I'll say is we think we've got 2 great choices here in terms of the 8.6 and 10 mg per kg doses, both of which, as you'll recall, we're currently evaluating on an adjusted ideal body weight basis in the context of the dose optimization cohort. So we're going to learn a lot as the year goes by as to the performance of these 2 doses, of course, in terms of efficacy, also in terms of safety. And on efficacy specifically, as we've been discussing for quite some time now, we do anticipate that at least our base case for our first registrational study, we do anticipate that overall survival will be our primary endpoint. And that, of course, means that ORR is really an important metric here for how the drug is performing, and this drug is performing extraordinarily well, as you said, 20% ORR at 8.6%, 32% at 10 MPK, that is remarkable activity. But we also have remarkable progression-free survival of 7 months as reported on March 16, and we are very keen to see how that translates into OS as the data matures with OS, of course, as I just mentioned, being our primary and most likely primary in the go-forward pivotal study. So we'll see. We'll see how these 2 doses deliver in terms of all of these different metrics, and we'll choose accordingly. Operator: And our next question will come from the line of Olivia Brayer of Cantor Fitzgerald. Olivia Brayer: For that second half data disclosure, can I just clarify that you guys plan to break out tolerability and efficacy for those 40 patients specifically in the optimization cohort? And if so, will we still get PFS and potentially even an early look at some OS data from those patients specifically? And then from a timing perspective, top line second half of this year, does that mean you'll likely follow it up with a presentation at a medical conference sometime in early 2027? And then I've got one quick follow-up on the new formulation with bev. Sean McCarthy: Yes. Thanks, Olivia. So yes, obviously, the 40 patients optimization cohorts is of high interest to us and others. And so we absolutely plan to report the full safety picture, which we gave an early look at in the March 16 disclosure. We gave an early look at the first 2 months of experience, which is very encouraging. So we plan to give a similar look for the full 40 patients by the end of the year, together with efficacy. And as I've already mentioned, PFS would certainly be a goal there to have PFS for those 40 patients. I think OS is going to be too early. We're just -- as we've reported today, we've completed enrollment, but that's been relatively recent. So I think OS is going to be immature. But we do anticipate having OS from the escalation and expansion phases, which I think will be particularly telling because remember that in those patients, those first escalation and expansion patients, we have not optimized our adverse event management plan, but we were still able to deliver 7 months of PFS, and we're optimistic that we'll have an encouraging OS number as we get to report that later in the year. In terms of venue for data updates, we do think a medical meeting this year is on the cards. Certainly, as we move into 2027, additional medical meetings, we're, of course, keeping our options open. Olivia Brayer: Okay. Very helpful. And then for the combination with bev, is there anything you guys can tell us at this point about the formulation work that you've done to get Varseta-M administered as an every 2 and 4-week dosing schedule instead of every 3 weeks? Or is there any data that you'll be sharing there at some point? Sean McCarthy: Well, there's no real formulation work that needs to be done. It's simply an adjustment of the schedule from Q3 to Q2 and then accordingly to Q4. And that's to match the -- as I just mentioned on the call, that's to match the established clinical use of bev in the FOLFOX/FOLFIRI setting on a 2-week schedule. So there's no additional formulation. It's simply a question of adjusting the frequency of dosing to match the use of bevacizumab in the marketplace today. Operator: And our next question will come from the line of Matt Biegler of OpCo. Matthew Biegler: Just kind of curious how you're seeing the emerging competitive profile here of Varseta-M versus the other ADCs that are also in development, Precem-TcT being one of them. And then I guess more importantly, do you think this is like a winner takes all, zero-sum game here with the Topo-1-based ADCs? Or do you think different patients might get different ADCs depending on certain health status, et cetera? Sean McCarthy: Thanks, Matt. Well, we certainly don't see this as winner takes all by any means. And I think that would be a very unusual scenario for an oncology drug in this class in an area of unmet need like this. I mean, our thinking is very different on that question. So first of all, with regard to Varseta-M, we have a first-in-class anti-EpCAM antibody drug conjugate. And again, I really can't emphasize how important it is to realize that we've done something really, really -- I'll use the word special with our technology to unlock the potential of EpCAM for the first time with our PROBODY therapeutic platform. Secondly, we really do believe that Varseta-M has the potential to be the best-in-class ADC for colorectal cancer. This drug is highly active. It's highly active in terms of its response rate. It's highly active in terms of its progression-free survival, and we'll see what it can deliver in terms of overall survival as we move forward. This is a very active drug, and we believe does have the potential to be best-in-class. So we're going all out with this drug to get it to the market as quickly as we can. We think it's highly competitive. And we think there's a ton of value to build in our company with this drug, most importantly, an enormous amount of benefit to bring to these patients. Operator: [Operator Instructions] Our next question will be coming from the line of Mitchell Kapoor of H.C. Wainwright. Unknown Analyst: This is [ Yan Zi ] sitting in for Mitchell. I was wondering, could you break -- so actually, with the enrollment now complete in the 40 patients dose optimization cohort, can you give any update on whether Grade 3 or higher diarrhea in the optimized adjusted ideal body weight plus prophylaxis population is still tracking closer to that initial 10% rate that was seen in the first 20 patients or whether it moves closer to something like the historical 25% to 30% range at the 8.6 and 10 mg per kg as follow-up has occurred? Sean McCarthy: Well, no new data today. That data will be coming. We're obviously -- we're highly encouraged by the initial data we presented on March 16 from the first couple of months of follow-up of the first 20 patients enrolled into the optimization cohorts with a rate of Grade 3 diarrhea of 10%. I think we commented at the time, and we've been very consistent about this over the last few months that our objective is, of course, to manage the rate of Grade 3 to the best of our ability with this updated AE management strategy that includes upfront use of loperamide and budesonide. It appears to be performing very well as of that first data update, and we're encouraged to see additional data now from the full 40 patients. That data will be shared later in the year. Our goal overall is to manage the Grade 3s into the 10% to 20% range. That we think is really the target. And that's based on our own research. It's based on a lot of conversations we've had. And quite honestly, a lot of work that's been published and presented by others over the last 6 or so months. So we're -- we feel we're very much on track, as I said in my prepared remarks, to get a strong handle on that particular aspect of the Varseta-M program. Unknown Analyst: I see. Curious also, so for an optimized regimen, how standardized is prophylaxis practice? Do you see any implementation friction that could matter in a community oncology setting if, for example, Varseta-M moves earlier in late line CRC? Sean McCarthy: We really don't. The upfront work that we're doing right now with these optimization cohorts is absolutely intended to pin down a prophylaxis strategy that will be readily translated into the community setting as we move into our first pivotal study and of course, as we bring the drug to the market. So it's a good question. It's an important question, and it's one that we've asked ourselves, and that is, again, just to restate a big part of why we're doing this upfront optimization work right now. But we -- right now, we don't see any challenges with the translation, if you like, of this updated AE management plan into a larger number of sites and ultimately into the commercial marketplace. Operator: I'm not showing any further questions in the queue. I would now like to turn the call back to Dr. Sean McCarthy, Chairman and CEO, for closing remarks. Sean McCarthy: Thank you. And again, I'd just like to thank everyone for joining us today. We're very excited about our progress here. I hope that comes across. And we really look forward to providing additional updates as the year progresses. Operator: And this concludes today's program. Thank you for participating. You may now disconnect. Before you buy stock in CytomX Therapeutics, consider this: The Motley Fool Stock Advisor analyst team just identified what they believe are the 10 best stocks for investors to buy now… and CytomX Therapeutics wasn’t one of them. The 10 stocks that made the cut could produce monster returns in the coming years. 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As with all our articles, The Motley Fool does not assume any responsibility for your use of this content, and we strongly encourage you to do your own research, including listening to the call yourself and reading the company's SEC filings. Please see our Terms and Conditions for additional details, including our Obligatory Capitalized Disclaimers of Liability. The Motley Fool has no position in any of the stocks mentioned. The Motley Fool has a disclosure policy. CytomX (CTMX) Q1 2026 Earnings Transcript was originally published by The Motley Fool

- Positive data announced from Phase 1 Dose Expansion Study of varsetatug masetecan (“Varseta-M”) EpCAM PROBODY® ADC in Patients with Advanced Colorectal Cancer (CRC) - - Enrollment of 40 patients in Varseta-M Dose Optimization completed; data update expected in 2H 2026 to inform monotherapy dose selection and potential registrational trial in late line CRC - - Varseta-M Phase 1 study evaluating combination with bevacizumab is ongoing with initial data expected by 1H 2027; Phase 1/2 Varseta-M chemotherapy combination study to be initiated in 2H 2026 - - Initiation of Phase 1 expansion cohort(s) in non-CRC indications planned for 2H 2026 - - Company to host conference call today at 5 p.m. ET / 2 p.m. PT - SOUTH SAN FRANCISCO, Calif., May 07, 2026 (GLOBE NEWSWIRE) -- CytomX Therapeutics, Inc. (Nasdaq: CTMX), a leader in the field of masked, conditionally activated biologics, today announced Q1 2026 financial results and provided a business update. “CytomX has continued to gain tremendous momentum in 2026 and we remain highly focused on executing against the multiple layers of potential value creation we see for Varseta-M. Our top priority is to advance this highly differentiated, first in class EpCAM ADC into a registrational study in late-line CRC while also investing to unlock the broader potential of Varseta-M in earlier line CRC and other cancers,” said Dr. Sean McCarthy, chairman and CEO of CytomX Therapeutics.” Continued Dr. McCarthy, “Strategically, we view Varseta-M as a company-building asset, uniquely enabled by the CytomX PROBODY therapeutic platform. Varseta-M is the only EpCAM targeted ADC in clinical development and is, we believe, ideally positioned to address the large unmet need in colorectal cancer as well as a broad range of EpCAM-expressing tumors. Based on the highly encouraging clinical results presented to-date and Varseta-M’s pan-tumor potential, we plan to execute with speed and focus to maximize benefit for people with cancer.” Pipeline Program Updates: Varsetatug masetecan (EpCAM PROBODY Topo-1 ADC, CX-2051) On March 16th 2026, CytomX announced positive data from the ongoing Phase 1 dose expansion study of Varseta-M in patients with advanced colorectal cancer (CRC). As of April 2026, enrollment into Varseta-M Dose Optimization cohorts was complete, having reached the goal of 40 total patients across the 8.6 mg/kg Q3W and 10 mg/kg Q3W doses1. Additional Phase 1 Varseta-M data, including data from ongoing dose optimization, is anticipated to be presented in the second half of 2026. This update is expected to support monotherapy dose selection and a potential registrational trial design in late line CRC. FDA interactions are planned in 2026 with goal of aligning on the potential first registrational study for Varseta-M monotherapy in advanced CRC starting in 1H 2027. A Phase 1 Varseta-M combination study with bevacizumab in CRC has commenced with an initial focus on determining combination dose(s) for later phase development, including in earlier lines of therapy. Varseta-M doses to be assessed in combination with bevacizumab will include Q2W and Q4W schedules to align with the approved bevacizumab CRC dose of 5 mg/kg Q2W. Initial clinical data are anticipated by 1H 2027. Phase 1/2 combination study including Varseta-M administered with bevacizumab, 5-fluorouracil, and leucovorin is planned to start in 2H 2026. Initiation of initial Phase 1 expansion cohort(s) in non-CRC indications is planned for 2H 2026. CX-801 (PROBODY Interferon alpha-2b) The CX-801 Phase 1 study in advanced melanoma is ongoing. The CX-801 monotherapy dose escalation portion of the study has reached the fourth dose level. CX-801 monotherapy has been generally well tolerated at dose levels exceeding the approved dose of unmasked IFNα2b.2 In May 2025, Phase 1 dose escalation of CX-801 in combination with KEYTRUDA® (pembrolizumab) was initiated. Dose escalation of CX-801 in combination with KEYTRUDA® is currently enrolling the third dose level. Biomarker data from the CX‑801 monotherapy study in advanced melanoma were presented at the 2025 Society for Immunotherapy of Cancer (SITC) Annual Meeting, reinforcing CX‑801’s mechanism of action and supporting the ongoing combination trial with KEYTRUDA®. Initial clinical data for CX-801 in combination with KEYTRUDA® in advanced melanoma is projected by the end of 2026. KEYTRUDA® is a registered trademark of Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA Corporate and Financial: Financial: Completed an equity follow-on offering in March 2026 with gross proceeds of $250 million. CytomX ended Q1 2026 with $346.7 million of cash, cash equivalents and investments with expected cash runway to at least the second half of 2028. Research Pipeline and Collaborations: CytomX has research collaborations with Amgen, Regeneron, and Moderna. Drug discovery programs continue in our research collaborations with a focus on bispecific immunotherapies, including T-cell engagers. Q1 2026 Financial Results: Cash, cash equivalents and investments totaled $346.7 million as of March 31, 2026, compared to $137.1 million as of December 31, 2025. Cash as of March 31, 2026 included $234.2 million of net proceeds from the completion of an underwritten public offering in March 2026. Total revenue was $10.3 million for the quarter ended March 31, 2026, compared to $50.9 million for the first quarter of 2025. The decrease in revenue was driven primarily by the completion of our performance obligations during 2025 in the collaborations with Bristol Myers Squibb and Amgen. Total operating expense for quarter ended March 31, 2026 was $29.9 million compared to $28.3 million for the first quarter ended March 31, 2025, an increase of $1.6 million. Research and development expenses increased by $0.4 million during the quarter ended March 31, 2026, to $19.2 million compared to $18.9 million for the quarter ended March 31, 2025. Research and development expenses increased primarily due to increased manufacturing activities for Varseta-M, partially offset by $1.7 million of restructuring expenses incurred in the first quarter of 2025. General and administrative expenses increased by $1.3 million during the quarter ended March 31, 2026, to $10.7 million, compared to $9.4 million for the quarter ended March 31, 2025. The general and administrative expenses for the first quarter of 2025 included $1.1 million of one-time restructuring expenses. About CytomX Therapeutics, Inc. CytomX is a clinical-stage, oncology-focused biopharmaceutical company focused on developing novel conditionally activated, masked PROBODY® therapeutics designed to be localized to the tumor microenvironment. By pioneering a novel pipeline of localized biologics, powered by its PROBODY therapeutic platform, CytomX’s vision is to create safer, more effective therapies for the treatment of cancer. CytomX’s robust and differentiated pipeline comprises therapeutic candidates across multiple treatment modalities including antibody-drug conjugates (“ADCs”), cytokines and T-cell engagers. CytomX’s clinical-stage pipeline includes varsetatug masetecan (Varseta-M; CX-2051) and CX-801. Varseta-M is a masked, conditionally activated ADC armed with a topoisomerase-1 inhibitor payload and directed toward epithelial cell adhesion molecule (EpCAM). EpCAM is a highly expressed tumor antigen that has previously been undruggable due to expression on normal tissues. Varseta-M is designed to open a therapeutic window for this high potential target and is initially being developed for the treatment of metastatic colorectal cancer. Varseta-M was discovered in collaboration with ImmunoGen, now part of AbbVie. CX-801 is a masked interferon alpha-2b PROBODY® cytokine with broad potential applicability in traditionally immuno-oncology sensitive as well as insensitive (cold) tumors. CX-801 is initially being developed for the treatment of metastatic melanoma. CytomX has established strategic collaborations with multiple leaders in oncology, including Amgen, Regeneron and Moderna. For more information about CytomX and how it is working to make conditionally activated treatments the new standard-of-care in the fight against cancer, visit www.cytomx.com and follow us on LinkedIn and X (formerly Twitter). CytomX Therapeutics Forward-Looking Statements This press release includes forward-looking statements. Such forward-looking statements involve known and unknown risks, uncertainties and other important factors that are difficult to predict, may be beyond CytomX’s control, and may cause the actual results, performance, or achievements to be materially different from any future results, performance or achievements expressed or implied in such statements, including those related to the future potential of partnerships or collaboration agreements and projected cash runway. Accordingly, you should not rely on any of these forward-looking statements, including those relating to the potential benefits, safety and efficacy or progress of CytomX’s or any of its collaborative partners’ product candidates, including varsetatug masetecan (Varseta-M) and CX-801, the potential benefits or applications of CytomX’s PROBODY® therapeutic platform, CytomX's planned interactions with the U.S. Food and Drug Administration and the ability to align on a potential registrational study design and regulatory pathway for Varseta-M, CytomX’s or its collaborative partners’ ability to develop and advance product candidates into and successfully complete clinical trials, including the ongoing and planned clinical trials of Varseta-M and CX-801 and the timing of initial and ongoing data availability for CytomX’s clinical trials, including Varseta-M and CX-801, and other development milestones. Risks and uncertainties that contribute to the uncertain nature of the forward-looking statements include: the unproven nature of CytomX’s novel PROBODY® therapeutic technology; uncertainties around the Company’s ability to raise sufficient funds to carry out its planned research and development; CytomX’s clinical trial product candidates are in the initial stages of clinical development and its other product candidates are currently in preclinical development, and the process by which preclinical and clinical development could potentially lead to an approved product is long and subject to significant risks and uncertainties, including the possibility that the results of preclinical research and early clinical trials, including initial Varseta-M clinical trial results, may not be predictive of future results; the possibility that CytomX’s clinical trials will not be successful; the possibility that current preclinical research may not result in additional product candidates; CytomX’s dependence on the success of Varseta-M and CX-801; CytomX’s reliance on third parties for the manufacture of the Company’s product candidates; possible regulatory developments in the United States and foreign countries, including China and the European Union; and the risk that we may incur higher costs than expected for research and development. Additional applicable risks and uncertainties include those relating to CytomX’s preclinical research and development, clinical development, and other risks identified under the heading "Risk Factors" included in CytomX’s Quarterly Report on Form 10-Q filed with the SEC on May 7, 2026. The forward-looking statements contained in this press release are based on information currently available to CytomX and speak only as of the date on which they are made. CytomX does not undertake and specifically disclaims any obligation to update any forward-looking statements, whether as a result of any new information, future events, changed circumstances or otherwise. PROBODY is a U.S. registered trademark of CytomX Therapeutics, Inc. All other trademarks are the properties of their respective owners. Company Contact: Chris Ogden SVP, Chief Financial Officer [email protected] Investor Contact: Precision AQ Stephanie Ascher [email protected] Media Contact: Precision AQ Colleen Ketchum [email protected] __________________ (1) The condensed balance sheet as of December 31, 2025 was derived from the audited financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2025. ——————————————————————— 1 8.6 mg/kg and 10 mg/kg based on adjusted ideal body weight (AIBW) 2 Merck & Co., Inc. (2018). Sylatron (peginterferon alfa-2b) prescribing information. U.S. Food and Drug Administration