MBX

One-year data demonstrated sustained benefit of once-weekly canvuparatide as a potential PTH replacement therapy in chronic hypoparathyroidism; Phase 3 pivotal trial now recruiting Initial Phase 1 data for MBX 4291, a GLP-1/GIP co-agonist prodrug for obesity, support potential for once-monthly dosing; data from 12-week MAD (Part C) on track for Q4 2026 Nomination of development candidate MBX 6180, a GLP-1/GIP/GCG triple agonist prodrug designed for once-monthly dosing, further expands obesity portfolio $418.6 million in cash and investments expected to support operations into 2029 CARMEL, Ind. and BURLINGTON, Mass., Aug. 06, 2026 (GLOBE NEWSWIRE) -- MBX Biosciences, Inc. (Nasdaq: MBX), a clinical-stage biopharmaceutical company focused on the discovery, development and commercialization of novel precision peptide therapies for the treatment of endocrine and metabolic disorders, today reported financial results for the second quarter ended June 30, 2026, and highlighted recent corporate progress. “The second quarter was highlighted by important milestones across our pipeline, including a first look at clinical data for MBX 4291 supporting its potential for true once-monthly dosing in obesity,” said Steve Hoerter, Chairman and Chief Executive Officer of MBX Biosciences. “In addition, we were proud to present the full Phase 2 and one-year OLE data for once-weekly canvuparatide, which demonstrated sustained benefit and the potential to become a best-in-class treatment for patients with chronic hypoparathyroidism. Now we look forward to dosing the first patients in our Phase 3 trial of canvuparatide this quarter and to presenting 12-week multiple ascending dose (MAD) data for MBX 4291 in the fourth quarter. With a strong balance sheet and an experienced team, we continue to leverage our proprietary PEP™ platform to develop differentiated, long-acting peptide therapies with the potential to meaningfully improve patients’ lives.” Second Quarter 2026 and Corporate Highlights Once-Weekly Canvuparatide for Hypoparathyroidism (HP) Full Phase 2 results and one-year OLE data presented at ENDO 2026: Results demonstrated sustained benefit of once-weekly canvuparatide as a potential PTH replacement therapy through one year, with findings consistent with restoration of systemic PTH activity through normalization of serum calcium, reduction of urine calcium excretion and restoration of bone metabolism, as well as a safety profile and pharmacokinetics supporting once-weekly dosing. Phase 3 trial of once-weekly canvuparatide now recruiting: MBX remains on track to initiate a Phase 3 pivotal trial of once-weekly canvuparatide in chronic hypoparathyroidism in Q3 2026. Clinical trial sites have been activated, and participants are currently being recruited and screened. The oPTimize Phase 3 pivotal, global, multicenter, randomized, double-blind placebo-controlled study will evaluate the safety, pharmacokinetics and efficacy of once-weekly canvuparatide in patients with HP. MBX 4291 and Expanding Obesity Portfolio Initial Phase 1 data for MBX 4291 supports potential for once-monthly dosing: Preliminary blinded data from the ongoing Phase 1 trial of MBX 4291, a dual GLP-1/GIP receptor agonist peptide prodrug, in adults with obesity demonstrated mean weight loss of 7% (range, 0–16%) at eight weeks (n=8, including 2 placebo) in the first multiple ascending dose (MAD) Part B cohort, with MBX 4291 generally well tolerated through eight weeks. The Company remains on track to report data from the first cohort of the 12-week MAD (Part C) in Q4 2026. Cohort C1 is evaluating a 30 mg (once-weekly x 4) + 120 mg (once-monthly) + 180 mg (once-monthly) titration regimen in adult participants with obesity (BMI ≥ 30). Nomination of MBX 6180 as GLP-1/GIP/GCG triple agonist prodrug development candidate: The Company today announced nomination of MBX 6180 as its lead GLP-1/GIP/glucagon (GCG) triple agonist prodrug candidate, further expanding its obesity pipeline to potentially address the full spectrum of patient needs. MBX 6180 combines GLP-1, GIP and GCG receptor agonist activity in a single construct. The differentiated design of MBX 6180 is intended to provide a pharmacokinetic profile supporting once-monthly dosing. The Company expects to present preclinical data from MBX 6180 at a scientific meeting in the fourth quarter of 2026. IND-enabling studies are now underway. Nomination of MBX 5765 as amycretin prodrug development candidate: In May 2026, MBX nominated MBX 5765 as its lead amycretin prodrug development candidate. Enabled by the Company's proprietary PEP™ platform, MBX 5765 combines GLP-1, GIP, GCG, and dual amylin and calcitonin receptor agonist (DACRA) activity in a single peptide construct. The differentiated mechanism of MBX 5765 is designed for once-monthly dosing, superior efficacy and improved tolerability. IND-enabling studies are ongoing. Corporate Executive Appointments to Support Next Phase of Growth: Steve Hoerter, current Executive Chairman of the MBX Board, was appointed Chairman and Chief Executive Officer, succeeding Kent Hawryluk. Mr. Hoerter joined the MBX Board of Directors in April 2025 and was appointed Executive Chairman in November 2025. In addition, John Smither, previously the Interim Chief Financial Officer, was appointed as Chief Financial Officer. Anticipated Milestones Canvuparatide Q3 2026: Initiation of pivotal Phase 3 oPTimize trial MBX 4291 Q4 2026: Results from the first cohort of the 12-week MAD (Part C) portion of the ongoing Phase 1 trial Second Quarter 2026 Financial Results Cash and Cash Equivalents and Marketable Securities: As of June 30, 2026, MBX had cash, cash equivalents and marketable securities of $418.6 million. Based on its current operating plan, the Company expects the combined cash, cash equivalents and marketable securities balance to fund operations into 2029. R&D Expenses: Research and development expenses for the three months ended June 30, 2026, were $31.0 million, compared to $17.7 million for the same period in 2025. The increase of $13.3 million was driven by an increase in start-up costs related to the canvuparatide Phase 3 clinical trial, ongoing conduct of the canvuparatide Phase 2 open-label extension clinical trial, ongoing conduct of the MBX 4291 Phase 1 clinical trial and timing of preclinical activities related to MBX 5765. G&A Expenses: General and administrative expenses for the three months ended June 30, 2026, were $9.9 million, compared to $4.1 million for the same period in 2025. The increase of $5.9 million was driven by higher personnel-related costs (including stock-based compensation) resulting from continued expansion of both our executive leadership team and general infrastructure to support growth in our operations Net Loss: Net loss for the three months ended June 30, 2026, was $37.1 million compared to a net loss of $19.4 million for the same period in 2025. About MBX Biosciences MBX Biosciences is a biopharmaceutical company focused on the discovery, development and commercialization of novel precision peptide therapies based on its proprietary PEP™ platform, for the treatment of endocrine and metabolic disorders. The Company is advancing a pipeline of novel candidates for endocrine and metabolic disorders with clinically validated targets, established endpoints for regulatory approval, significant unmet medical needs and large potential market opportunities. The Company’s pipeline includes canvuparatide (MBX 2109) for the treatment of chronic hypoparathyroidism in Phase 3 development; and an obesity portfolio that includes MBX 4291 in Phase 1 development and MBX 5765 and MBX 6180 in preclinical development, as well as additional discovery candidates. The Company is based in Carmel, Indiana and Burlington, Massachusetts. To learn more, please visit the company website at www.mbxbio.com and follow it on LinkedIn. About MBX’s Proprietary Precision Endocrine Peptide (PEP™) Platform MBX was founded by global leaders with a transformative approach to peptide drug design and development. Leveraging this expertise, the Company designed its proprietary Precision Endocrine Peptide™ (PEP™) platform to overcome the key limitations of unmodified and modified peptide therapies and to improve clinical outcomes and simplify disease management for patients. PEPs are selectively engineered to have optimized pharmaceutical properties, including extended time-action profiles and consistent drug concentrations with low peak-to-trough concentration ratios, consistent exposure to target tissues, and less frequent dosing. Forward-Looking Statements This press release contains “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934, each as amended. The words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “would” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. These forward-looking statements include, but are not limited to, express or implied statements regarding: MBX Biosciences’ expectations regarding the further advancement of its pipeline of programs in endocrine and metabolic disorders, including timing of initiation of a Phase 3 trial for canvuparatide in Q3 2026; the potential for canvuparatide to be a once-weekly PTH replacement therapy; the expected timing of the Phase 1 readout for MBX 4291; the timing of additional obesity candidate nominations; the potential for MBX Biosciences to develop therapies for obesity dosed once monthly; and expectations regarding MBX Biosciences’ uses of capital, expenses and financial results, including the anticipated cash runway timing. Forward-looking statements are based on management’s current expectations and are subject to risks and uncertainties that could negatively affect MBX Biosciences’ business, operating results, financial condition and stock value. Factors that could cause actual results to differ materially from those currently anticipated include: risks relating to the Company’s research and development activities; MBX Biosciences’ ability to execute on its strategy including obtaining the requisite regulatory approvals on the expected timeline, if at all; uncertainties relating to preclinical and clinical development activities; the Company’s dependence on third parties to conduct clinical trials, manufacture its product candidates and develop and commercialize its product candidates, if approved; MBX Biosciences’ ability to attract, integrate and retain key personnel; risks related to the Company’s financial condition and need for substantial additional funds in order to complete development activities and commercialize a product candidate, if approved; risks related to regulatory developments and approval processes of the U.S. Food and Drug Administration and comparable foreign regulatory authorities; risks related to establishing and maintaining MBX Biosciences’ intellectual property protections; risks related to the competitive landscape for MBX Biosciences’ product candidates; and final audit adjustments and other developments that may arise that would cause MBX Biosciences’ expectations with respect to the estimate of cash, cash equivalents and marketable securities as of December 31, 2025 to differ, perhaps materially, from the financial results that will be reflected in MBX Biosciences’ audited consolidated financial statements for the fiscal year ended December 31, 2025; as well as other risks described in “Risk Factors,” in MBX Biosciences’ Quarterly Report on Form 10-Q for the three months ended June 30, 2026, Annual Report on Form 10-K for the year ended December 31, 2025, as well as subsequent filings filed with the Securities and Exchange Commission (SEC). MBX Biosciences expressly disclaims any obligation or undertaking to release publicly any updates or revisions to any forward-looking statements contained herein to reflect any change in its expectations or any changes in events, conditions or circumstances on which any such statement is based, except as required by law, and claims the protection of the safe harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995. MBX Biosciences uses and intends to continue to use its Investor Relations website as a means of disclosing material nonpublic information and for complying with its disclosure obligations under Regulation FD. Accordingly, investors should monitor the Company's Investor Relations website, in addition to following the Company's press releases, SEC filings, public conference calls, presentations, and webcasts. Media Contact:George SheaWe. [email protected] Investor Contact:Jim DeNikeMBX [email protected]

MBX Biosciences recently reported full 12-week Phase 2 Avail trial results and one-year open-label extension data for once-weekly canvuparatide in adults with chronic hypoparathyroidism, showing higher responder rates versus placebo, sustained calcium control, kidney function improvements, and a generally well tolerated safety profile. An interesting angle for investors is the pharmacokinetic profile, with low peak-to-trough variability supporting convenient once-weekly dosing as the company plans a Phase 3 trial start in the third quarter of 2026. We’ll now examine how these Phase 2 and one-year extension results, particularly the sustained responder rate, shape MBX Biosciences’ investment narrative. The best AI stocks today may lie beyond giants like Nvidia and Microsoft. Find the next big opportunity with these 14 smaller AI-focused companies with strong growth potential through early-stage innovation in machine learning, automation, and data intelligence that could fund your retirement. For MBX Biosciences to make sense as a stock, you have to believe that canvuparatide can become a meaningful parathyroid hormone replacement in chronic hypoparathyroidism and that management can translate that into a focused commercial story while funding an early obesity pipeline. The new Phase 2 and one-year extension data broadly support the scientific pillar of that thesis, with sustained responder rates, clean pharmacokinetics and no fresh safety concerns, so they appear to reinforce rather than reset the near term catalyst path around the planned Phase 3 start in the third quarter of 2026. The sharp share pullback after the update suggests expectations around magnitude of benefit or timelines may have been ahead of the data. The bigger issues still look familiar: MBX has no revenue, rising losses of about US$86.61m, recent dilution, an inexperienced but expanding leadership bench and heavy dependence on a single late stage asset to justify a relatively full price to book multiple. However, investors should also factor in how much future funding may be needed before any potential product launch. The valuation report we've compiled suggests that MBX Biosciences' current price could be inflated. The Simply Wall St Community’s single fair value estimate at US$69.09 sits against a backdrop of zero revenue, widening losses and fresh dilution, inviting you to question how much hinges on canvuparatide’s Phase 3 execution. Explore another fair value estimate on MBX Biosciences - why the stock might be worth as much as 95% more than the current price! Disagree with this assessment? Extraordinary investment returns rarely come from following the herd, so go with your instincts. A great starting point for your MBX Biosciences research is our analysis highlighting 5 important warning signs that could impact your investment decision. Our free MBX Biosciences research report provides a comprehensive fundamental analysis summarized in a single visual - the Snowflake - making it easy to evaluate MBX Biosciences' overall financial health at a glance. Markets shift fast. These stocks won't stay hidden for long. Get the list while it matters: The future of work is here. Discover the 33 top robotics and automation stocks leading the charge in AI-driven automation and industrial transformation. Invest in the nuclear renaissance through our list of 88 elite nuclear energy infrastructure plays powering the global AI revolution. Capitalize on the AI infrastructure supercycle with our selection of the 48 best 'picks and shovels' of the AI gold rush converting record-breaking demand into massive cash flow. 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 MBX. Have feedback on this article? Concerned about the content? Get in touch with us directly. Alternatively, email [email protected]

MBX Biosciences Inc. (NASDAQ:MBX) shares dropped 19.6% in premarket trading on Friday despite the company reporting encouraging one-year clinical data for its investigational treatment canvuparatide in patients with chronic hypoparathyroidism. The clinical-stage biopharmaceutical company released updated findings from its 12-week Avail Phase 2 study alongside one-year results from an ongoing open-label extension trial evaluating once-weekly canvuparatide in adult patients with the rare endocrine disorder. The open-label extension study showed that 57% of patients met the responder criteria after one year of treatment. While slightly below the 63% responder rate recorded at the 12-week stage of the Phase 2 trial, the data continued to demonstrate meaningful long-term efficacy. During the Phase 2 study, 63% of patients receiving canvuparatide achieved the primary composite endpoint, compared with 31% of patients treated with placebo. The primary endpoint required patients to maintain albumin-adjusted serum calcium levels within the normal range while remaining independent from conventional therapy. MBX reported a 90% retention rate among participants who entered the open-label extension study, with the vast majority remaining on treatment through the one-year mark. According to the company, the data suggest that canvuparatide successfully restores systemic parathyroid hormone (PTH) activity, supporting multiple markers of disease control. These included normalization of serum calcium levels, reduced urinary calcium excretion, improvements in bone metabolism, and enhanced kidney function. Mean serum calcium levels remained within the normal range throughout the one-year treatment period. At the same time, average 24-hour urine calcium levels declined from baseline measurements, indicating improved calcium regulation. Researchers also observed improvements in estimated glomerular filtration rate (eGFR), a key indicator of kidney function. The gains in eGFR first became apparent by Week 12 and were maintained throughout the one-year follow-up period. Canvuparatide continued to demonstrate a favorable safety profile during the extension study. The company reported no new safety concerns and no treatment-related serious adverse events. Most treatment-emergent adverse events were classified as mild or moderate in severity. Injection-site reactions were reported in approximately 10% of patients receiving the therapy. MBX Biosciences said development of canvuparatide remains on track, with the company continuing preparations for a pivotal Phase III study. Management expects to initiate the Phase III trial during the third quarter of 2026. Despite the positive efficacy and safety findings, investors appeared to focus on the modest decline in responder rates compared with the earlier Phase II results, contributing to the sharp decline in the stock following the announcement. MBX Biosciences stock price

Results from Phase 2 trial of once-weekly canvuparatide accepted for oral presentation at ENDO in June 2026 Phase 3 trial of once-weekly canvuparatide on track to initiate in Q3 2026 Appointment of Mark Soued as Chief Commercial Officer adds launch and commercialization expertise Company to host Obesity Day on May 11th featuring initial blinded data from ongoing MBX 4291 Phase 1 trial and update on expanding obesity portfolio $440.0 million in cash and investments expected to support operations into 2029 CARMEL, Ind. and BURLINGTON, Mass., May 07, 2026 (GLOBE NEWSWIRE) -- MBX Biosciences, Inc. (Nasdaq: MBX), a clinical-stage biopharmaceutical company focused on the discovery, development and commercialization of novel precision peptide therapies for the treatment of endocrine and metabolic disorders, today reported financial results for the first quarter ended March 31, 2026, and highlighted recent corporate progress. “We continue to make excellent progress across our pipeline in 2026, including advancement toward initiation of our Phase 3 trial of once-weekly canvuparatide following a successful End-of-Phase 2 meeting with the FDA,” said Kent Hawryluk, President and Chief Executive Officer of MBX Biosciences. “Now we look forward to presenting our full Phase 2 Avail™ results, including one-year open-label extension data for canvuparatide, while continuing to advance a growing obesity pipeline enabled by our Precision Endocrine Peptide (PEP™) platform. With a world-class leadership team and a strong balance sheet, we are well positioned to execute on our goal of delivering improved, long-acting and well-tolerated peptide therapies for patients.” First Quarter 2026 and Corporate Highlights Once-Weekly Canvuparatide for Hypoparathyroidism Presentation of Phase 2 results and one-year follow-up data in June: Results from the 12-week AvailTM trial of once-weekly canvuparatide have been accepted for oral presentation at the Endocrine Society’s ENDO 2026 annual meeting in Chicago on Saturday, June 13, 2026. In addition, MBX will present one-year open-label extension (OLE) data for once-weekly canvuparatide at the 3rd Parathyroid Summit during the ENDO 2026 annual meeting in Chicago on Friday, June 12, 2026. Phase 3 trial of once-weekly canvuparatide on track to initiate in Q3 2026: Following a successful End-of-Phase 2 meeting with the U.S. Food and Drug Administration (FDA), MBX remains on track to initiate a Phase 3 confirmatory trial of once-weekly canvuparatide in chronic hypoparathyroidism in Q3 2026. MBX 4291 and Expanding Obesity Pipeline Obesity Day to highlight MBX 4291 and expanding obesity pipeline: MBX announced plans to host an Obesity Day on May 11, 2026, featuring initial blinded data from the ongoing Phase 1 trial of MBX 4291 and an update on its expanding obesity pipeline. For more details and to register for the event, click here. The Company remains on track to report data from the 12-week multiple ascending dose (MAD) portion of the ongoing Phase 1 trial of MBX 4291 in Q4 2026. Growing obesity pipeline designed to address full spectrum of patient needs: MBX plans to nominate additional obesity development candidates enabled by its PEPTM platform, each designed for potential once-monthly dosing with improved tolerability. These candidate nominations include an amycretin prodrug, on track for this quarter, and a GLP-1/GIP/glucagon receptor (GCGR) triple-agonist prodrug, expected in Q3 2026. Corporate Expansion of leadership team adds launch and commercialization expertise: Earlier today, MBX announced the appointment of Mark Soued as Chief Commercial Officer. Mr. Soued is a seasoned commercial biopharma executive with deep experience building and growing global commercial organizations. Most recently he led Alnylam Pharmaceuticals’ US amyloidosis business, including the category-defining launch of AMVUTTRA® in ATTR cardiomyopathy. Anticipated Milestones Canvuparatide Q2 2026: Oral presentation of Phase 2 AvailTM results and one-year OLE data during ENDO 2026 Q3 2026: Initiation of Phase 3 trial in chronic hypoparathyroidism MBX 4291 and Expanding Obesity Pipeline Q2 2026: Nomination of amycretin prodrug candidate Q3 2026: Nomination of GLP-1/GIP/GCGR triple-agonist prodrug candidate Q4 2026: Results from 12-week MAD portion of ongoing Phase 1 trial of MBX 4291 Imapextide Q2 2026: Results from Phase 2a STEADI™ trial of imapextide for the treatment of post-bariatric hypoglycemia (PBH) First Quarter 2026 Financial Results Cash and Cash Equivalents and Marketable Securities: As of March 31, 2026, MBX had cash, cash equivalents and marketable securities of $440.0 million. Based on its current operating plan, the Company expects the combined cash, cash equivalents and marketable securities balance to fund operations into 2029. R&D Expenses: Research and development expenses for the three months ended March 31, 2026, were $18.5 million, compared to $22.4 million for the same period in 2025. The decrease of $3.9 million was driven by higher costs for the canvuparatide Phase 2 clinical trial and timing of preclinical studies and manufacturing activities for MBX 4291 in the first quarter of 2025. G&A Expenses: General and administrative expenses for the three months ended March 31, 2026, were $8.8 million, compared to $4.1 million for the same period in 2025. The increase of $4.7 million was driven by increased personnel-related costs resulting from the continued expansion of the Company’s infrastructure to support growth in operations and separation-related costs. Net Loss: Net loss for the three months ended March 31, 2026, was $23.5 million compared to a net loss of $23.9 million for the same period in 2025. About MBX Biosciences MBX Biosciences is a biopharmaceutical company focused on the discovery, development and commercialization of novel precision peptide therapies based on its proprietary PEP™ platform, for the treatment of endocrine and metabolic disorders. The Company is advancing a pipeline of novel candidates for endocrine and metabolic disorders with clinically validated targets, established endpoints for regulatory approval, significant unmet medical needs and large potential market opportunities. The Company’s pipeline includes canvuparatide (MBX 2109) for the treatment of chronic hypoparathyroidism preparing for Phase 3 development; an obesity portfolio that includes MBX 4291 in Phase 1 development, as well as multiple discovery and pre-clinical obesity candidates; and imapextide (MBX 1416) for the treatment of PBH in Phase 2 development. The Company is based in Carmel, Indiana and Burlington, Massachusetts. To learn more, please visit the Company website at www.mbxbio.com and follow it on LinkedIn. About MBX’s Proprietary Precision Endocrine Peptide (PEP™) Platform MBX was founded by global leaders with a transformative approach to peptide drug design and development. Leveraging this expertise, the Company designed its proprietary Precision Endocrine Peptide™ (PEP™) platform to overcome the key limitations of unmodified and modified peptide therapies and to improve clinical outcomes and simplify disease management for patients. PEPs are selectively engineered to have optimized pharmaceutical properties, including extended time-action profiles and consistent drug concentrations with low peak-to-trough concentration ratios, consistent exposure to target tissues, and less frequent dosing. Forward-Looking Statements This press release contains “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934, each as amended. The words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “would” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. These forward-looking statements include, but are not limited to, express or implied statements regarding: MBX Biosciences’ expectations regarding the further advancement of its pipeline of programs in endocrine and metabolic disorders, including timing of initiation of a Phase 3 trial for canvuparatide in Q3 2026 and clinical data presentation at ENDO 2026 in Q2 2026; the potential for canvuparatide to be a once-weekly PTH replacement therapy; the expected timing of the Phase 1 readout for MBX 4291 and planned obesity day presentation; the timing of additional obesity candidate nominations in Q2 and Q3 2026; the potential for MBX Biosciences to develop therapies for obesity dosed once monthly; the expected timing for the Phase 2a STEADI™ trial results; the ability of MBX 1416 to be a treatment of PBH; the potential contributions of the new Chief Commercial Officer; and expectations regarding MBX Biosciences’ uses of capital, expenses and financial results, including the anticipated cash runway timing. Forward-looking statements are based on management’s current expectations and are subject to risks and uncertainties that could negatively affect MBX Biosciences’ business, operating results, financial condition and stock value. Factors that could cause actual results to differ materially from those currently anticipated include: risks relating to the Company’s research and development activities; MBX Biosciences’ ability to execute on its strategy including obtaining the requisite regulatory approvals on the expected timeline, if at all; uncertainties relating to preclinical and clinical development activities; the Company’s dependence on third parties to conduct clinical trials, manufacture its product candidates and develop and commercialize its product candidates, if approved; MBX Biosciences’ ability to attract, integrate and retain key personnel; risks related to the Company’s financial condition and need for substantial additional funds in order to complete development activities and commercialize a product candidate, if approved; risks related to regulatory developments and approval processes of the U.S. Food and Drug Administration and comparable foreign regulatory authorities; risks related to establishing and maintaining MBX Biosciences’ intellectual property protections; risks related to the competitive landscape for MBX Biosciences’ product candidates; and final audit adjustments and other developments that may arise that would cause MBX Biosciences’ expectations with respect to the estimate of cash, cash equivalents and marketable securities as of December 31, 2025 to differ, perhaps materially, from the financial results that will be reflected in MBX Biosciences’ audited consolidated financial statements for the fiscal year ended December 31, 2025; as well as other risks described in “Risk Factors,” in MBX Biosciences’ Quarterly Report on Form 10-Q for the three months ended March 31, 2026, Annual Report on Form 10-K for the year ended December 31, 2025, as well as subsequent filings filed with the Securities and Exchange Commission (SEC). MBX Biosciences expressly disclaims any obligation or undertaking to release publicly any updates or revisions to any forward-looking statements contained herein to reflect any change in its expectations or any changes in events, conditions or circumstances on which any such statement is based, except as required by law, and claims the protection of the safe harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995. MBX Biosciences uses and intends to continue to use its Investor Relations website as a means of disclosing material nonpublic information and for complying with its disclosure obligations under Regulation FD. Accordingly, investors should monitor the Company's Investor Relations website, in addition to following the Company's press releases, SEC filings, public conference calls, presentations, and webcasts. Media Contact: George Shea We. Communications [email protected] Investor Contact: Jim DeNike MBX Biosciences [email protected]

MISSISSAUGA, ON / ACCESS Newswire / March 26, 2026 / Microbix Biosystems Inc. (TSX:MBX)(OTCQB:MBXBF) ("Microbix®" or the Company"), a life sciences innovator, manufacturer, and exporter, announces the voting results from the Annual Meeting of Shareholders of the Company (the "Meeting") which was held on March 25, 2026. At the Meeting, 27.44% of the issued and outstanding shares were represented. Shareholders voted in favour of all resolutions brought before the Meeting. Details of all resolutions that were voted upon are set out in the Management Information Circular (the "Circular") dated February 6, 2026. The Circular is available on the Company's website (https://www.microbix.com) and on SEDAR+ (https://www.sedarplus.ca). All of the board of directors nominees listed in the Circular were re-elected as directors of Microbix. Results of the vote were as follows: Shareholders also approved a resolution re-appointing the Company's auditors, Ernst & Young LLP, with 96.66% of the votes cast in favour. The slides of management's presentation at the Meeting have been posted at https://www.microbix.com. About Microbix Biosystems Inc. Microbix Biosystems Inc. creates proprietary biological products for human health, with over 120 skilled employees and revenues of C$ 18.6 million in its latest fiscal year (2025). It makes a wide range of critical ingredients and devices for the global diagnostics industry, notably antigens for immunoassays and its laboratory quality assessment products (QAPs™) and reference materials (QUANTDx™) that support clinical lab proficiency testing, enable assay development and validation, or help ensure the quality of clinical diagnostic workflows. Its antigens drive the antibody tests of approximately 100 diagnostics makers, while QAPs or QUANTDx are sold to clinical lab accreditation organizations, diagnostics companies, and clinical labs. Microbix QAPs are now available in over 30 countries, supported by a network of international distributors. Microbix is ISO 9001 & 13485 accredited, U.S. FDA registered, Australian TGA registered, Health Canada establishment licensed, and provides IVDR-compliant CE marked products. Microbix also applies its biological expertise and infrastructure to develop other proprietary products and technologies, most notably Kinlytic® urokinase, a biologic thrombolytic drug used to treat blood clots and reagents to support molecular diagnostic testing (e.g., its DxTM™ for patient sample collection. Microbix is traded on the TSX and OTCQX, and headquartered in Mississauga, Ontario, Canada. Forward-Looking Information This news release includes "forward-looking information," as such term is defined in applicable securities laws. Forward-looking information includes, without limitation, discussions about the Meeting or its relevance, Microbix's or others' products or services, business and business results, goals or outlook, risks associated with financial results and stability, development projects such as those referenced in its presentations, regulatory compliance and approvals, access to and sales to foreign jurisdictions, engineering and construction, production (including control over costs, quality, quantity or timeliness of delivery), currency exchange rates, maintaining adequate working capital or raising new capital on acceptable terms or at all, and other similar statements about anticipated future events, conditions or results that are not historical facts. These statements reflect management's current estimates, beliefs, intentions, and expectations; they are not guarantees of future performance. Microbix cautions that all forward-looking information is inherently uncertain and actual performance may be affected by a number of material factors, many of which are beyond its control. Accordingly, actual future events, conditions and results may differ materially from the estimates, beliefs, intentions, and expectations expressed or implied in the forward-looking information. All statements are made as of the date of this news release and represent Microbix's judgement as of the date of this new release, and it is under no obligation to update or alter any forward-looking information except as required by applicable law. Please visit https://microbix.com or https://www.sedarplus.ca for recent Microbix news and filings. For further information, please contact Microbix at: Copyright © 2026 Microbix Biosystems Inc. Microbix®, DxTM™, Kinlytic®, QAPs™, and QUANTDx™ are trademarks of Microbix Biosystems Inc. SOURCE: Microbix Biosystems Inc. View the original press release on ACCESS Newswire

Phase 3 trial of once-weekly canvuparatide remains on track to initiate in Q3 2026 following recently completed, successful End-of-Phase 2 meeting with FDA 12-week MAD Phase 1 data from MBX 4291 for obesity anticipated in Q4 2026 Planned nomination of amycretin and GLP-1/GIP/glucagon receptor triple-agonist development candidates for obesity expected in Q2 and Q3 2026 $459.1 million in pro forma cash and investments as of December 31, 2025, including $85.4 million in net proceeds from top-tier institutional investors through ATM program; expected to support operations into 2029 CARMEL, Ind., March 12, 2026 (GLOBE NEWSWIRE) -- MBX Biosciences, Inc. (Nasdaq: MBX), a clinical-stage biopharmaceutical company focused on the discovery, development and commercialization of novel precision peptide therapies for the treatment of endocrine and metabolic disorders, today reported financial results for the fourth quarter and full year ended December 31, 2025, and highlighted recent corporate progress. “2025 was a year of continued growth and execution for MBX, highlighted by the clinical validation of our Precision Endocrine Peptide (PEP™) platform,” said Kent Hawryluk, President and Chief Executive Officer of MBX Biosciences. “Following a successful End-of-Phase 2 meeting with the FDA, we now have a clear path to initiate our Phase 3 trial of once-weekly canvuparatide. We are also advancing a growing obesity pipeline, built on our clinically validated PEPTM platform and designed for once-monthly dosing and improved tolerability. We look forward to a data-rich year ahead and to continuing our pursuit of bringing differentiated and best-in-class medicines to patients.” Fourth Quarter 2025 and Recent Corporate Highlights Once-Weekly Canvuparatide for Hypoparathyroidism (HP) End-of-Phase 2 FDA meeting for once-weekly canvuparatide completed: FDA feedback supported advancement into a Phase 3 trial and trial design elements have now been selected, including the number of patients, primary endpoint and key secondary endpoints, as well as dose selection, titration schedule and duration of the study. Initiation of the Phase 3 program remains on track for Q3 2026. EU Orphan Drug Designation granted for canvuparatide: The European Medicines Agency granted orphan drug designation to canvuparatide for the treatment of chronic hypoparathyroidism, supporting its continued clinical development in Europe. MBX expects to present the complete 12-week dataset and one-year follow-up data from the Phase 2 AvailTM trial for once-weekly canvuparatide at a medical conference in Q2 2026. MBX4291 and Early Pipeline Programs for Obesity MBX 4291 advancing through Phase 1: MBX 4291, a GLP-1/GIP co-agonist prodrug designed for potential once-monthly dosing, continues to advance through Phase 1, with 12-week multiple ascending dose data on track to be reported in Q4 2026. Obesity portfolio expansion planned in 2026: MBX expects to nominate two additional obesity development candidates enabled by its PEPTM platform, each designed for potential once-monthly dosing with improved tolerability, including an amycretin prodrug targeted for nomination in Q2 2026 and a GLP-1/GIP/glucagon receptor (GCGR) triple-agonist prodrug candidate targeted for nomination in Q3 2026. Long-Acting Imapextide (MBX 1416) for Post-Bariatric Hypoglycemia (PBH) Phase 2a trial of imapextide (MBX 1416) ongoing: Results from the ongoing Phase 2a STEADITM trial of potential once-weekly imapextide for post-bariatric hypoglycemia are expected in Q2 2026. Corporate Board Appointment: In January 2026, the Company announced the appointment of Laurie Stelzer to its Board of Directors as an independent director and Audit Committee Chair, adding strategic, commercial, and financial leadership to support the Company’s advancement toward late-stage development and long-term growth objectives. Leadership Addition: In March 2026, MBX announced the appointment of Karen Basbaum, MBA, as Chief Business Officer. Ms. Basbaum brings more than two decades of leadership in corporate strategy, business development, and strategic transactions across the biotechnology and pharmaceutical industries. Strengthened Balance Sheet: In February 2026, the Company raised $85.4 million in net proceeds through its At-the-Market (ATM) facility, with participation from new and existing institutional investors. Anticipated Milestones Canvuparatide Q2 2026: Presentation of full Phase 2 AvailTM results at a medical conference, including data from the open-label extension Q3 2026: Initiation of Phase 3 trial in chronic hypoparathyroidism MBX 4291 and Early Obesity Pipeline Q2 2026: Nomination of amycretin prodrug candidate Q3 2026: Nomination of GLP-1/GIP/GCGR triple-agonist prodrug candidate Q4 2026: Results from 12-week multiple ascending dose portion of Phase 1 trial of MBX 4291 Imapextide Q2 2026: Phase 2a STEADI™ trial results of imapextide for the treatment of post-bariatric hypoglycemia Fourth Quarter and Full Year 2025 Financial Results Cash and Cash Equivalents and Marketable Securities: As of December 31, 2025, MBX Biosciences had cash, cash equivalents and marketable securities of $373.7 million. Subsequently, on February 4, 2026, the Company raised an additional $85.4 million in net proceeds through its ATM program, resulting in pro forma cash and investments of $459.1 million as of December 31, 2025. Based on its current operating plan, the Company expects the combined cash, cash equivalents and marketable securities balance to fund operations into 2029. R&D Expenses: Research and development expenses for the three months and full year ended December 31, 2025, were $19.8 million and $79.2 million, respectively, compared to $15.2 million and $57.4 million for the same periods in 2024. The increases of $4.6 million and $21.8 million respectively were driven by costs associated with the ongoing MBX 4291 Phase 1 clinical trial, the canvuparatide Phase 2 AvailTM clinical trial and preparation activities for a Phase 3 clinical trial in canvuparatide. G&A Expenses: General and administrative expenses for the three months and full year ended December 31, 2025, were $6.0 million and $18.9 million, respectively, compared to $3.4 million and $10.8 million for the same periods in 2024. The increases of $2.6 million and $8.1 million, respectively, were driven by increased personnel-related costs as the Company expanded its infrastructure to support its growth in operations and higher professional fees to support operations as a public company. Net Loss: Net loss for the three months ended December 31, 2025, was $22.1 million compared to a net loss of $15.6 million for the same period in 2024. Net loss for the full year ended December 31, 2025 was $87.0 million compared to a net loss of $61.9 million for the same period in 2024. About MBX Biosciences MBX Biosciences is a biopharmaceutical company focused on the discovery, development and commercialization of novel precision peptide therapies based on its proprietary PEP™ platform, for the treatment of endocrine and metabolic disorders. The Company is advancing a pipeline of novel candidates for endocrine and metabolic disorders with clinically validated targets, established endpoints for regulatory approval, significant unmet medical needs and large potential market opportunities. The Company’s pipeline includes canvuparatide (MBX 2109) for the treatment of chronic hypoparathyroidism (HP) preparing for Phase 3 development; an obesity portfolio that includes MBX 4291 in Phase 1 development, as well as multiple discovery and pre-clinical obesity candidates; and imapextide (MBX 1416) for the treatment of post-bariatric hypoglycemia (PBH) in Phase 2 development. The Company is based in Carmel, Indiana. To learn more, please visit the Company website at www.mbxbio.com and follow it on LinkedIn. About MBX’s Proprietary Precision Endocrine Peptide (PEP™) Platform MBX was founded by global leaders with a transformative approach to peptide drug design and development. Leveraging this expertise, the Company designed its proprietary Precision Endocrine Peptide™ (PEP™) platform to overcome the key limitations of unmodified and modified peptide therapies and to improve clinical outcomes and simplify disease management for patients. PEPs are selectively engineered to have optimized pharmaceutical properties, including extended time-action profiles and consistent drug concentrations with low peak-to-trough concentration ratios, consistent exposure to target tissues, and less frequent dosing. Forward-Looking Statements This press release contains “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934, each as amended. The words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “would” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. These forward-looking statements include, but are not limited to, express or implied statements regarding: MBX Biosciences’ expectations regarding the further advancement of its pipeline of programs in endocrine and metabolic disorders, including timing of initiation of a Phase 3 trial for canvuparatide in Q3 2026 and clinical data presentation in Q2 2026; statements regarding MBX Biosciences’ delivery of differentiated endocrine and metabolic compounds allow patient freedom; MBX Biosicences’ pro forma cash and investments as a result of sales under the ATM program; the contributions of its board of directors; the potential for canvuparatide to be a once-weekly PTH replacement therapy; the expected timing of the Phase 1 readout for MBX 4291 and candidate nominations; the potential for MBX Biosciences to develop therapies for obesity dosed once monthly; the expected timing for the Phase 2a STEADI™ trial results; the ability of MBX 1416 to be a treatment of PBH; and expectations regarding MBX Biosciences’ uses of capital, expenses and financial results, including the anticipated cash runway timing. Forward-looking statements are based on management’s current expectations and are subject to risks and uncertainties that could negatively affect MBX Biosciences’ business, operating results, financial condition and stock value. Factors that could cause actual results to differ materially from those currently anticipated include: risks relating to the Company’s research and development activities; MBX Biosciences’ ability to execute on its strategy including obtaining the requisite regulatory approvals on the expected timeline, if at all; uncertainties relating to preclinical and clinical development activities; the Company’s dependence on third parties to conduct clinical trials, manufacture its product candidates and develop and commercialize its product candidates, if approved; MBX Biosciences’ ability to attract, integrate and retain key personnel; risks related to the Company’s financial condition and need for substantial additional funds in order to complete development activities and commercialize a product candidate, if approved; risks related to regulatory developments and approval processes of the U.S. Food and Drug Administration and comparable foreign regulatory authorities; risks related to establishing and maintaining MBX Biosciences’ intellectual property protections; risks related to the competitive landscape for MBX Biosciences’ product candidates; and final audit adjustments and other developments that may arise that would cause MBX Biosciences’ expectations with respect to the estimate of cash, cash equivalents and marketable securities as of December 31, 2025 to differ, perhaps materially, from the financial results that will be reflected in MBX Biosciences’ audited consolidated financial statements for the fiscal year ended December 31, 2025; as well as other risks described in “Risk Factors,” in MBX Biosciences’ Quarterly Report on Form 10-Q for the three months ended September 30, 2025, Annual Report on Form 10-K for the year ended December 31, 2025, as well as subsequent filings filed with the Securities and Exchange Commission (SEC). MBX Biosciences expressly disclaims any obligation or undertaking to release publicly any updates or revisions to any forward-looking statements contained herein to reflect any change in its expectations or any changes in events, conditions or circumstances on which any such statement is based, except as required by law, and claims the protection of the safe harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995. MBX Biosciences uses and intends to continue to use its Investor Relations website as a means of disclosing material nonpublic information and for complying with its disclosure obligations under Regulation FD. Accordingly, investors should monitor the Company's Investor Relations website, in addition to following the Company's press releases, SEC filings, public conference calls, presentations, and webcasts. Media Contact: George Shea We. Communications [email protected] Investor Contact: Jim DeNike MBX Biosciences [email protected]

Reported positive topline results from the Phase 2 Avail™ trial of once-weekly canvuparatide in hypoparathyroidism (HP) Completed upsized public offering, raising approximately $200 million in gross proceeds $391.7 million in cash, cash equivalents and marketable securities as of September 30, 2025; expected to support operations into 2029 Updated 2026 corporate milestones include clinical data for three Precision Endocrine Peptide™ (PEP) programs and initiation of a Phase 3 trial in HP CARMEL, Ind., Nov. 06, 2025 (GLOBE NEWSWIRE) -- MBX Biosciences, Inc. (Nasdaq: MBX), a clinical-stage biopharmaceutical company focused on the discovery and development of novel precision peptide therapies for the treatment of endocrine and metabolic disorders, today reported financial results for the third quarter ended September 30, 2025, and highlighted recent corporate progress. “The third quarter of 2025 marked another quarter of significant execution as we reported positive topline results from our Phase 2 Avail™ trial of once-weekly canvuparatide,” said Kent Hawryluk, President and Chief Executive Officer of MBX Biosciences. “These strong results support our belief that canvuparatide has the potential to be best-in-class in hypoparathyroidism, an estimated multibillion dollar market. We are preparing for meetings with US and EU regulatory agencies, initiation of our Phase 3 trial and future commercialization. With a clinically validated PEP™ platform, and cash runway into 2029, MBX is well positioned to execute on our value-creating milestones in 2026 across our pipeline and become a leading, fully integrated endocrine and metabolic disease biopharma company.” In November 2025, the Company's board of directors appointed Steve Hoerter to serve as executive chairperson, to support the Company’s executive team with his perspective and commercialization experience, as the Company prepares for the start of a Phase 3 trial and begins pre-commercial activities. Mr. Hoerter joined the Company’s board of directors earlier this year, bringing more than 30 years of pharmaceutical commercialization and executive leadership experience, most recently as President and Chief Executive Officer of Deciphera Pharmaceuticals until its $2.4 billion acquisition by Ono Pharmaceutical in 2024. Jim Cornelius also retired from the board as of October 31, 2025, after more than five years of valuable service. Third Quarter 2025 and Recent Corporate Highlights Hypoparathyroidism (HP): Canvuparatide (MBX 2109) Positive topline results from Phase 2 Avail™ trial of once-weekly canvuparatide support Phase 3 advancement: The Company announced that once-weekly canvuparatide achieved the primary composite endpoint in the Phase 2 Avail™ trial in adults with hypoparathyroidism, with 63% of canvuparatide-treated patients achieving responder status at 12 weeks, and 79% achieving responder status at six months in the ongoing open-label extension study. Canvuparatide is the Company’s potential once-weekly parathyroid hormone (PTH) peptide prodrug. The Company expects to conduct an End of Phase 2 meeting with the U.S. Food and Drug Administration and Scientific Advice with the European Medicines Agency in Q1 2026. The Company also intends to present Avail™ Phase 2 results at a medical meeting in Q2 2026; report one-year results from its ongoing canvuparatide open-label extension study in Q2 2026; and initiate a Phase 3 trial in Q3 2026. Obesity: MBX 4291 Dosed first participant in Phase 1 trial of MBX 4291 for the treatment of obesity (NCT07142707): The Company initiated its first clinical trial in obesity with the dosing of the first participant in the Phase 1 study of MBX 4291, a Precision Endocrine Peptide™ (PEP™) glucagon-like peptide-1 (GLP-1)/glucose-dependent insulinotropic polypeptide (GIP) co-agonist prodrug. The three-part, randomized, double-blind, placebo-controlled trial is designed to evaluate safety, tolerability, pharmacokinetics, and pharmacodynamics of single and multiple ascending (SAD and MAD) doses in adults with obesity. Planned 12-week MAD portion: Following completion of Parts A and B, the Company plans to evaluate multiple ascending doses of MBX 4291, or matching placebo, administered over 12 weeks in up to two cohorts consisting of 30 participants each in a 2:1 randomization ratio. Participants are expected to receive up to a total of 12 study intervention administrations one week or one week and one month apart with increasing doses of MBX 4291 and will be followed for 120 days after the first dose. Results from the planned 12-week MAD portion are expected in Q4 2026. Post-bariatric Hypoglycemia (PBH): Imapextide (MBX 1416) Dosed first patient in Phase 2a STEADI™ trial of imapextide (MBX1416) for post-bariatric hypoglycemia (NCT07029412): The Company initiated a Phase 2a, open-label exploratory study to evaluate preliminary efficacy of subcutaneous imapextide in patients with PBH. Approximately ten patients aged 18 to 65 years with a history of hypoglycemia following Roux-en-Y or sleeve gastrectomy will be included in the study. Participants will undergo three mixed-meal tolerance tests, one at baseline and again 48 hours after each imapextide administration, to evaluate the effect of imapextide on increasing post-prandial glucose nadir. Imapextide’s effect in reducing post-prandial insulin and C-peptide peaks will also be evaluated. Results are expected in Q2 2026. Corporate Completed upsized public offering: The Company completed an upsized public offering of its common stock, raising approximately $200 million in gross proceeds before deducting underwriting discounts, commissions, and other offering expenses. Anticipated Milestones Canvuparatide Q1 2026: End of Phase 2 meeting and EMA Scientific Advice Q2 2026: Presentation of Phase 2 results at a medical meeting Q2 2026: Phase 2 one-year open label extension study data Q3 2026: Phase 3 canvuparatide HP trial initiation MBX 4291 Q4 2026: Results from 12-week multiple ascending dose portion of Phase 1 trial of MBX 4291 for the treatment of obesity Imapextide Q2 2026: Phase 2a STEADI™ trial results of imapextide for the treatment of post-bariatric hypoglycemia (PBH) Third Quarter 2025 Financial Results Cash and Cash Equivalents and Marketable Securities: As of September 30, 2025, the Company had cash, cash equivalents and marketable securities of $391.7 million, which includes proceeds from its upsized public offering. Based on its current operating plan, management expects the combined cash and marketable securities balance to fund operations into 2029. R&D Expenses: Research and development expenses for the three months ended September 30, 2025, were $19.3 million compared to $16.7 million for the same period in 2024. The increase of $2.6 million was driven by costs associated with the ongoing MBX 4291 Phase 1 clinical trial and the canvuparatide Phase 2 clinical trial. G&A Expenses: General and administrative expenses for the three months ended September 30, 2025, were $4.7 million compared to $2.9 million for the same period in 2024. The increase of $1.8 million was driven by increased personnel-related costs as the Company expanded its infrastructure to support its growth in operations as a public company. Net Loss: Net loss for the three months ended September 30, 2025, was $21.6 million compared to a net loss of $18.1 million for the same period in 2024. About MBX Biosciences MBX Biosciences is a biopharmaceutical company focused on the discovery and development of novel precision peptide therapies based on its proprietary PEP™ platform, for the treatment of endocrine and metabolic disorders. The Company is advancing a pipeline of novel candidates for endocrine and metabolic disorders with clinically validated targets, established endpoints for regulatory approval, significant unmet medical needs and large potential market opportunities. The Company’s pipeline includes canvuparatide (MBX 2109) for the treatment of chronic hypoparathyroidism (HP) preparing for Phase 3 development; imapextide (MBX 1416) for the treatment of post-bariatric hypoglycemia (PBH) in Phase 2 development; and an obesity portfolio that includes MBX 4291 in Phase 1 development, as well as multiple discovery and pre-clinical obesity candidates. The Company is based in Carmel, Indiana. To learn more, please visit the Company website at www.mbxbio.com and follow it on LinkedIn. About MBX’s Proprietary Precision Endocrine Peptide (PEP™) Platform MBX was founded by global leaders with a transformative approach to peptide drug design and development. Leveraging this expertise, the Company designed its proprietary Precision Endocrine Peptide™ (PEP™) platform to overcome the key limitations of unmodified and modified peptide therapies and to improve clinical outcomes and simplify disease management for patients. PEPs are selectively engineered to have optimized pharmaceutical properties, including extended time-action profiles and consistent drug concentrations with low peak-to-trough concentration ratios, consistent exposure to target tissues, and less frequent dosing. Forward-Looking Statements This press release contains “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934, each as amended. The words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “would” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. These forward-looking statements include, but are not limited to, express or implied statements regarding: MBX Biosciences’ expectations regarding the Phase 2 trial of canvuparatide, including timing of results from the open-label extension and timing of initiation of a Phase 3 trial; the potential for canvuparatide to be a best-in-class, once-weekly PTH replacement therapy; the expected timing of results from the Phase 2a trial for imapextide; statements related to the ability of imapextide to be a treatment of PBH; the expected timing of results from the Phase 1 trial for MBX 4291; and expectations regarding MBX Biosciences’ uses of capital, expenses and financial results, including the anticipated cash runway timing. Forward-looking statements are based on management’s current expectations and are subject to risks and uncertainties that could negatively affect MBX Biosciences’ business, operating results, financial condition and stock value. Factors that could cause actual results to differ materially from those currently anticipated include: risks relating to the Company’s research and development activities; MBX Biosciences’ ability to execute on its strategy including obtaining the requisite regulatory approvals on the expected timeline, if at all; uncertainties relating to preclinical and clinical development activities; the Company’s dependence on third parties to conduct clinical trials, manufacture its product candidates and develop and commercialize its product candidates, if approved; MBX Biosciences’ ability to attract, integrate and retain key personnel; risks related to the Company’s financial condition and need for substantial additional funds in order to complete development activities and commercialize a product candidate, if approved; risks related to regulatory developments and approval processes of the U.S. Food and Drug Administration and comparable foreign regulatory authorities; risks related to establishing and maintaining MBX Biosciences’ intellectual property protections; and risks related to the competitive landscape for MBX Biosciences’ product candidates; as well as other risks described in “Risk Factors,” in MBX Biosciences’ Quarterly Report on Form 10-Q for the three months ended September 30, 2025, Annual Report on Form 10-K for the year ended December 31, 2024 filed with the Securities and Exchange Commission (SEC), as well as subsequent filings with the SEC. MBX Biosciences expressly disclaims any obligation or undertaking to release publicly any updates or revisions to any forward-looking statements contained herein to reflect any change in its expectations or any changes in events, conditions or circumstances on which any such statement is based, except as required by law, and claims the protection of the safe harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995. MBX uses and intends to continue to use its Investor Relations website as a means of disclosing material nonpublic information and for complying with its disclosure obligations under Regulation FD. Accordingly, investors should monitor the Company's Investor Relations website, in addition to following the Company's press releases, SEC filings, public conference calls, presentations, and webcasts. Media Contact: Cassidy McClain Inizio Evoke Comms [email protected] (619) 694-6291 Investor Contact: Jim DeNike MBX Biosciences [email protected]

On September 22, 2025, MBX Biosciences announced positive topline results from its Phase 2 Avail trial, with once-weekly canvuparatide achieving the primary endpoint with statistical significance and a high responder rate at 6 months in adults with chronic hypoparathyroidism. An impressive 94% of patients who completed the study chose to enter the open-label extension, highlighting ongoing patient engagement and interest in the therapy’s long-term potential. We'll explore how the advancement to a Phase 3 trial for canvuparatide factors into MBX Biosciences' evolving investment narrative. Uncover the next big thing with financially sound penny stocks that balance risk and reward. For shareholders of MBX Biosciences, the big picture focuses on believing in the company’s ability to transition promising clinical results, like the recent Phase 2 win for canvuparatide, into an eventual commercial product. The strong efficacy and patient retention reported in the latest trial are likely to be a meaningful short-term catalyst, boosting optimism ahead of the planned Phase 3 trial in 2026. The company’s follow-on equity offering alongside these results also signals an intention to secure additional funding, which may impact existing shareholders in the near term but could strengthen the balance sheet for next-phase development efforts. However, risks persist, including the ongoing lack of revenue, continued net losses, a new management team, and a need to outperform established competitors if canvuparatide is eventually approved. Those factors are now seen in a new light, as positive clinical progress could support market confidence, but execution risks remain central to the MBX story. But, with no operating revenue, funding needs should remain front of mind for investors. Our valuation report here indicates MBX Biosciences may be overvalued. Among two Simply Wall St Community fair value estimates, views stretch from US$5.34 to a peak of US$53.43 per share. This wide range shows how differently market participants view MBX’s future as clinical milestones unfold, especially as funding requirements and execution risk become more prominent. Explore these viewpoints to weigh how optimism and uncertainty may affect performance. Explore 2 other fair value estimates on MBX Biosciences - why the stock might be worth less than half the current price! Disagree with this assessment? Create your own narrative in under 3 minutes - extraordinary investment returns rarely come from following the herd. A great starting point for your MBX Biosciences research is our analysis highlighting 4 important warning signs that could impact your investment decision. Our free MBX Biosciences research report provides a comprehensive fundamental analysis summarized in a single visual - the Snowflake - making it easy to evaluate MBX Biosciences' overall financial health at a glance. Markets shift fast. These stocks won't stay hidden for long. Get the list while it matters: Rare earth metals are the new gold rush. Find out which 30 stocks are leading the charge. Find companies with promising cash flow potential yet trading below their fair value. Trump has pledged to "unleash" American oil and gas and these 22 US stocks have developments that are poised to benefit. 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 MBX. Have feedback on this article? Concerned about the content? Get in touch with us directly. Alternatively, email [email protected]

Topline results for the Phase 2 Avail™ trial of canvuparatide in hypoparathyroidism on track for Q3 2025 Imapextide (MBX 1416) Phase 2a trial initiation in patients with post-bariatric hypoglycemia anticipated in Q3 2025 MBX 4291 Phase 1 trial initiation in obesity anticipated in Q3 2025 $224.9 million in cash, cash equivalents and marketable securities as of June 30, 2025; expected to support operations into mid-2027 CARMEL, Ind., Aug. 07, 2025 (GLOBE NEWSWIRE) -- MBX Biosciences, Inc. (Nasdaq: MBX), a clinical-stage biopharmaceutical company focused on the discovery and development of novel precision peptide therapies for the treatment of endocrine and metabolic disorders, today reported financial results for the second quarter ended June 30, 2025, and highlighted recent corporate progress. “We are pleased to report continuous clinical development progress across our entire pipeline of Precision Endocrine Peptide (PEP) product candidates with a number of value-creating milestones anticipated in the second half of this year,” said Kent Hawryluk, President and Chief Executive Officer of MBX Biosciences. “We look forward to sharing topline results from our Phase 2 Avail™ trial of canvuparatide in hypoparathyroidism this quarter. In addition, we are on track to initiate a Phase 2a clinical trial for imapextide, a peptide therapy for the treatment of post-bariatric hypoglycemia, and a Phase 1 trial evaluating MBX 4291 in patients with obesity, both in this quarter.” Second Quarter 2025 and Recent Corporate Highlights Hypoparathyroidism (HP): Canvuparatide (MBX 2109) Phase 2 topline data from Avail trial expected in Q3 2025. Topline results from the Phase 2 Avail trial of canvuparatide, a potential long-acting, once-weekly parathyroid hormone (PTH) peptide prodrug candidate, are on track to be reported in the third quarter of 2025. Post-bariatric Hypoglycemia (PBH): Imapextide (MBX 1416) Patient screening underway in Phase 2a trial: The Company has completed an end-of-Phase 1 meeting and a Phase 2a clinical trial evaluating imapextide, a long-acting glucagon-like peptide 1 (GLP-1) receptor antagonist for the treatment of PBH, is expected to begin in the third quarter of 2025. Obesity: MBX 4291 Phase 1 trial to initiate Q3 2025: MBX 4291, a GLP-1/glucose-dependent insulinotropic polypeptide (GIP) co-agonist prodrug is being developed as a once-monthly treatment for patients with obesity. In June, the Company submitted an investigational new drug (IND) application for MBX 4291 and received clearance to proceed in July. A Phase 1 trial initiation is anticipated in the third quarter of 2025. Corporate Leadership team additions: In June, MBX appointed Andreas Moraitis, M.D., as Senior Vice President of Clinical Development overseeing clinical advancement of canvuparatide. Second Quarter 2025 Financial Results Cash and Cash Equivalents and Marketable Securities: As of June 30, 2025, MBX Biosciences had cash, cash equivalents and marketable securities of $224.9 million. Based on its current operating plan, management expects the combined cash, cash equivalents and marketable securities balance to fund operations into mid-2027. R&D Expenses: Research and development expenses for the three months ended June 30, 2025, were $17.7 million compared to $14.4 million for the same period in 2024. The increase of $3.3 million was driven by costs associated with ongoing IND-enabling studies for MBX 4291 and the ongoing canvuparatide Phase 2 clinical trial. G&A Expenses: General and administrative expenses for the three months ended June 30, 2025, were $4.1 million compared to $2.3 million for the same period in 2024. The increase of $1.8 million was driven by increased personnel-related costs as the Company expanded its infrastructure to support its growth in operations as a public company. Net Loss: Net loss for the three months ended June 30, 2025, was $19.4 million compared to a net loss of $15.9 million for the same period in 2024. About MBX Biosciences MBX Biosciences is a biopharmaceutical company focused on the discovery and development of novel precision peptide therapies based on its proprietary PEP™ platform, for the treatment of endocrine and metabolic disorders. The Company is advancing a pipeline of novel candidates for endocrine and metabolic disorders with clinically validated targets, established endpoints for regulatory approval, significant unmet medical needs and large potential market opportunities. The Company’s pipeline includes canvuparatide (MBX 2109) for the treatment of chronic hypoparathyroidism (HP) in Phase 2 development; imapextide (MBX 1416) for the treatment of post-bariatric hypoglycemia (PBH) in Phase 2 development; and an obesity portfolio that includes MBX 4291, in Phase 1 development, as well as multiple discovery and pre-clinical obesity candidates. The Company is based in Carmel, Indiana. To learn more, please visit the Company website at www.mbxbio.com and follow it on LinkedIn. About MBX’s Proprietary Precision Endocrine Peptide (PEP™) Platform MBX was founded by global leaders with a transformative approach to peptide drug design and development. Leveraging this expertise, the Company designed its proprietary Precision Endocrine Peptide™ (PEP™) platform to overcome the key limitations of unmodified and modified peptide therapies and to improve clinical outcomes and simplify disease management for patients. PEPs are selectively engineered to have optimized pharmaceutical properties, including extended time-action profiles and consistent drug concentrations with low peak-to-trough concentration ratios, consistent exposure to target tissues, and less frequent dosing. Forward-Looking Statements This press release contains “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934, each as amended. The words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “would” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. These forward-looking statements include, but are not limited to, express or implied statements regarding: MBX Biosciences’ expectations regarding the Phase 2 Avail™ trial of canvuparatide, including the timing of topline results; statements related to the potential for canvuparatide to be a once-weekly PTH replacement therapy; the expected timing for the Phase 2a trial for imapextide and statements related to an end-of-phase 1 meeting with the FDA; statements related to the ability of imapextide to be a treatment of PBH; the expected timing of the initiation of a Phase 1 trial for MBX 4291; and expectations regarding MBX Biosciences’ uses of capital, expenses and financial results, including the anticipated cash runway timing. Forward-looking statements are based on management’s current expectations and are subject to risks and uncertainties that could negatively affect MBX Biosciences’ business, operating results, financial condition and stock value. Factors that could cause actual results to differ materially from those currently anticipated include: risks relating to the Company’s research and development activities; MBX Biosciences’ ability to execute on its strategy including obtaining the requisite regulatory approvals on the expected timeline, if at all; uncertainties relating to preclinical and clinical development activities; the Company’s dependence on third parties to conduct clinical trials, manufacture its product candidates and develop and commercialize its product candidates, if approved; MBX Biosciences’ ability to attract, integrate and retain key personnel; risks related to the Company’s financial condition and need for substantial additional funds in order to complete development activities and commercialize a product candidate, if approved; risks related to regulatory developments and approval processes of the U.S. Food and Drug Administration and comparable foreign regulatory authorities; risks related to establishing and maintaining MBX Biosciences’ intellectual property protections; and risks related to the competitive landscape for MBX Biosciences’ product candidates; as well as other risks described in “Risk Factors,” in MBX Biosciences’ Quarterly Report on Form 10-Q for the three months ended June 30, 2025, Annual Report on Form 10-K for the year ended December 31, 2024 filed with the Securities and Exchange Commission (SEC), as well as subsequent filings with the SEC. MBX Biosciences expressly disclaims any obligation or undertaking to release publicly any updates or revisions to any forward-looking statements contained herein to reflect any change in its expectations or any changes in events, conditions or circumstances on which any such statement is based, except as required by law, and claims the protection of the safe harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995. MBX uses and intends to continue to use its Investor Relations website as a means of disclosing material nonpublic information and for complying with its disclosure obligations under Regulation FD. Accordingly, investors should monitor the Company's Investor Relations website, in addition to following the Company's press releases, SEC filings, public conference calls, presentations, and webcasts. Media Contact: Katie Beach Oltsik Inizio Evoke Comms [email protected] (937) 232-4889 Investor Contact: Jim DeNike MBX Biosciences [email protected]

Topline results for the Phase 2 Avail™ evaluating canvuparatide in patients with hypoparathyroidism expected in 3Q 2025 Investigational New Drug submission for MBX 4291 on track for 2Q 2025 $240.8 million in cash, cash equivalents and marketable securities as of March 31, 2025; expected to support operations into mid-2027 CARMEL, Ind., May 12, 2025 (GLOBE NEWSWIRE) -- MBX Biosciences, Inc. (Nasdaq: MBX), a clinical-stage biopharmaceutical company focused on the discovery and development of novel precision peptide therapies for the treatment of endocrine and metabolic disorders, today reported financial results for the first quarter ended March 31, 2025, and highlighted recent corporate progress. “We’ve followed up on our strong execution in 2024 with excellent progress on all our programs enabled by a strong balance sheet and cash position,” said Kent Hawryluk, President and Chief Executive Officer of MBX Biosciences. “Following full enrollment of the Phase 2 Avail trial investigating canvuparatide for the treatment of hypoparathyroidism, we look forward to reporting top line results in the third quarter of 2025. We’re also on track to submit our investigational new drug (IND) application this quarter for MBX 4291, a novel glucagon-like peptide 1 (GLP-1)/glucose-dependent insulinotropic polypeptide (GIP) co-agonist prodrug for treating obesity. In addition to these milestones, we also expect to begin a Phase 2 trial for MBX 1416 in post-bariatric hypoglycemia patients in the second half of this year and share further details on our additional obesity candidates currently in pre-clinical development.” First Quarter 2025 and Recent Corporate Highlights Hypoparathyroidism (HP): Canvuparatide (MBX 2109) Phase 2 topline data from Avail trial expected in 3Q 2025. MBX completed enrollment of 64 participants, exceeding its original enrollment target, in the Phase 2 Avail trial of canvuparatide, a potential long-acting parathyroid once-weekly hormone peptide prodrug candidate, in the first quarter of 2025. Topline results are expected in the third quarter of 2025. Obesity: MBX 4291 IND application submission on track for Q2 2025: MBX 4291, a GLP-1/GIP co-agonist prodrug, is being developed as a once-monthly treatment for obesity. The Company expects to submit an IND application for MBX 4291 this quarter. Post-bariatric Hypoglycemia (PBH): MBX 1416 Phase 2 trial expected to be initiated in 2H 2025: In January, MBX reported Phase 1 top line results for its MBX 1416 long-acting GLP-1 receptor antagonist developed for the treatment of PBH. A Phase 2 trial is expected to be initiated in the second half of 2025 following completion of an End of Phase 1 meeting with the U.S. Food & Drug Administration (FDA). Corporate New Independent Director: Earlier in April, MBX announced the appointment of Steve Hoerter as an independent director to the Company’s board of directors. As a veteran executive with a wealth of pharmaceutical leadership and commercialization, as well as extensive board experience, Mr. Hoerter will be instrumental in supporting MBX Biosciences during the next stage of the Company’s growth. First Quarter 2025 Financial Results Cash and Cash Equivalents and Marketable Securities: As of March 31, 2025, MBX Biosciences had cash, cash equivalents and marketable securities of $240.8 million. Based on its current operating plan, management expects the combined cash, cash equivalents and marketable securities balance to fund operations into mid-2027. R&D Expenses: Research and development expenses for the three months ended March 31, 2025, were $22.4 million compared to $11.0 million for the same period in 2024. The increase of $11.4 million was driven by costs associated with ongoing IND-enabling studies for MBX 4291 and the ongoing Phase 2 Avail trial of canvuparatide. G&A Expenses: General and administrative expenses for the three months ended March 31, 2025, were $4.1 million compared to $2.3 million for the same period in 2024. The increase of $1.8 million was driven by increased personnel-related costs as the Company expanded its infrastructure to support its growth in operations. Net Loss: Net loss for the three months ended March 31, 2025, was $23.9 million compared to a net loss of $12.3 million for the same period in 2024. About MBX Biosciences MBX Biosciences is a biopharmaceutical company focused on the discovery and development of novel precision peptide therapies based on its proprietary PEP™ platform, for the treatment of endocrine and metabolic disorders. The Company is advancing a pipeline of novel candidates for endocrine and metabolic disorders with clinically validated targets, established endpoints for regulatory approval, significant unmet medical needs and large potential market opportunities. The Company’s pipeline includes canvuparatide (MBX 2109) for the treatment of chronic hypoparathyroidism (HP) in Phase 2 development; MBX 1416 for the treatment of post-bariatric hypoglycemia (PBH) in Phase 1 development; and an obesity portfolio that includes MBX 4291, with an IND filing anticipated in Q2 2025, as well as multiple discovery and pre-clinical obesity candidates. The Company is based in Carmel, Indiana. To learn more, please visit the Company website at www.mbxbio.com and follow it on LinkedIn. About MBX’s Proprietary Precision Endocrine Peptide (PEP™) Platform MBX was founded by global leaders with a transformative approach to peptide drug design and development. Leveraging this expertise, the Company designed its proprietary Precision Endocrine Peptide™ (PEP™) platform to overcome the key limitations of unmodified and modified peptide therapies and to improve clinical outcomes and simplify disease management for patients. PEPs are selectively engineered to have optimized pharmaceutical properties, including extended time-action profiles and consistent drug concentrations with low peak-to-trough concentration ratios, consistent exposure to target tissues, and less frequent dosing. Forward-Looking Statements This press release contains “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934, each as amended. The words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “would” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. These forward-looking statements include, but are not limited to, express or implied statements regarding: MBX Biosciences’ expectations regarding the Phase 2 Avail™ trial of canvuparatide, including the timing of topline results; the expected timing of the IND application submission for MBX 4291; statements related to MBX 2491 being developed as a once-monthly treatment for obesity; expectations regarding development of MBX Biosciences’ additional obesity candidates currently in pre-clinical development; the expected timing for the Phase 2 trial for MBX 1416 in PBH patients; statements related to the ability of MBX 1416 to be a treatment of PBH; statements related to the contribution of MBX Biosciences’ leadership and board of directors; and expectations regarding MBX Biosciences’ uses of capital, expenses and financial results, including the anticipated cash runway timing. Forward looking statements are based on management’s current expectations and are subject to risks and uncertainties that could negatively affect MBX Biosciences’ business, operating results, financial condition and stock value. Factors that could cause actual results to differ materially from those currently anticipated include: risks relating to the Company’s research and development activities; MBX Biosciences’ ability to execute on its strategy including obtaining the requisite regulatory approvals on the expected timeline, if at all; uncertainties relating to preclinical and clinical development activities; the Company’s dependence on third parties to conduct clinical trials, manufacture its product candidates and develop and commercialize its product candidates, if approved; MBX Biosciences’ ability to attract, integrate and retain key personnel; risks related to the Company’s financial condition and need for substantial additional funds in order to complete development activities and commercialize a product candidate, if approved; risks related to regulatory developments and approval processes of the U.S. Food and Drug Administration and comparable foreign regulatory authorities; risks related to establishing and maintaining MBX Biosciences’ intellectual property protections; and risks related to the competitive landscape for MBX Biosciences’ product candidates; as well as other risks described in “Risk Factors,” in MBX Biosciences’ Quarterly Report on Form 10-Q for the three months ended March 31, 2025 filed with the Securities and Exchange Commission (SEC), its Annual Report on Form 10-K for the year ended December 31, 2024 filed with the SEC, as well as subsequent filings with the SEC. MBX Biosciences expressly disclaims any obligation or undertaking to release publicly any updates or revisions to any forward-looking statements contained herein to reflect any change in its expectations or any changes in events, conditions or circumstances on which any such statement is based, except as required by law, and claims the protection of the safe harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995. MBX uses and intends to continue to use its Investor Relations website as a means of disclosing material nonpublic information and for complying with its disclosure obligations under Regulation FD. Accordingly, investors should monitor the Company's Investor Relations website, in addition to following the Company's press releases, SEC filings, public conference calls, presentations, and webcasts. Media Contact: Katie Beach Oltsik Inizio Evoke Comms [email protected] (937) 232-4889 Investor Contact: Jim DeNike MBX Biosciences [email protected]

Enrollment complete in Phase 2 Avail™ trial of canvuparatide in hypoparathyroidism; topline results on track for Q3 2025 MBX 1416 Phase 2 trial in patients with post-bariatric hypoglycemia expected to begin in 2H 2025 Investigational New Drug submission anticipated in Q2 2025 for MBX 4291 in obesity $262.1 million in cash, cash equivalents and marketable securities as of December 31, 2024; expected to support operations into mid-2027 CARMEL, Ind., March 17, 2025 (GLOBE NEWSWIRE) -- MBX Biosciences, Inc. (Nasdaq: MBX), a clinical-stage biopharmaceutical company focused on the discovery and development of novel precision peptide therapies for the treatment of endocrine and metabolic disorders, today reported financial results for the fourth quarter and full year ended December 31, 2024, and highlighted recent corporate progress. “MBX is entering 2025 with strong momentum following significant and transformational progress in 2024,” said Kent Hawryluk, President and Chief Executive Officer of MBX Biosciences. “We are poised to deliver Phase 2 clinical data on our lead program in hypoparathyroidism, canvuparatide, with topline results from our Avail™ trial anticipated in the third quarter of 2025. Additionally, we are well-positioned to enter the clinic with our first obesity candidate later this year, pending clearance of our investigational new drug (IND) application with the U.S. Food and Drug Administration (FDA). Finally, we look forward to initiating a Phase 2 trial evaluating MBX 1416 in post-bariatric hypoglycemia (PBH) patients in the second half of 2025.” Fourth Quarter 2024 and Recent Corporate Highlights Hypoparathyroidism (HP): Canvuparatide (MBX 2109) Completed Enrollment in Phase 2 Avail Trial in HP patients: In March 2025, MBX announced the completion of enrollment of 64 patients with HP in the Phase 2 Avail trial of canvuparatide, the Company’s potential long-acting parathyroid once-weekly hormone (PTH) peptide prodrug. Topline results from the randomized, double-blind, placebo-controlled 12-week trial are anticipated in the third quarter of 2025. Published Phase 1 Trial Results: In December 2024, MBX announced the publication of a peer-reviewed article highlighting results from the Phase 1 study of canvuparatide titled “MBX 2109, a Once-Weekly Parathyroid Hormone Replacement Therapy Prodrug: Phase 1, First-in-Human, Randomized Trial” in The Journal of Clinical Endocrinology and Metabolism (JCEM) and can be accessed here. Post-bariatric Hypoglycemia (PBH): MBX 1416 Positive results from MBX 1416 Phase 1 trial support Phase 2 advancement: In January 2025, the Company announced positive topline results from its Phase 1 single ascending dose and multiple ascending dose clinical trial of MBX 1416 in healthy adult volunteers. MBX 1416 is the Company’s long-acting glucagon-like peptide 1 (GLP-1) receptor antagonist in development for the treatment of PBH. MBX anticipates initiating a Phase 2 study of MBX 1416 in patients with PBH in the second half of 2025 following completion of an End-of-Phase 1 meeting with the FDA. Obesity: MBX 4291 IND filing on track for Q2 2025: MBX expects to submit an IND application to the FDA in the second quarter of 2025 for MBX 4291, the Company’s GLP-1/GIP co-agonist prodrug for the potential once-monthly treatment of obesity. Corporate Leadership Team Additions: In March 2025, the Company announced the appointments of Chatan Charan, Ph.D. as Senior Vice President, Pharmaceutical Development and Chemistry, Manufacturing and Controls and Mark Hope as Senior Vice President, Regulatory and Quality, adding additional expertise in support of the company’s ongoing advancement and expansion of its novel product candidates. Fourth Quarter and Full Year 2024 Financial Results Cash and Cash Equivalents and Marketable Securities: As of December 31, 2024, MBX Biosciences had cash, cash equivalents and marketable securities of $262.1 million. Based on its current operating plan, the Company expects the combined cash, cash equivalents and marketable securities balance to fund operations into mid-2027. R&D Expenses: Research and development expenses for the three months and full year ended December 31, 2024, were $15.2 million and $57.4 million, respectively, compared to $7.7 million and $28.5 million for the same periods in 2023. The increases of $7.5 million and $28.9 million, respectively, were driven by costs associated with ongoing IND-enabling studies for MBX 4291 and the ongoing canvuparatide Phase 2 clinical trial. G&A Expenses: General and administrative expenses for the three months and full year ended December 31, 2024, were $3.4 million and $10.8 million, respectively, compared to $2.3 million and $6.8 million for the same periods in 2023. The increases of $1.1 million and $4.0 million, respectively, were driven by increased personnel-related costs as the Company expanded its infrastructure to support its growth in operations. Net Loss: Net loss for the three months ended December 31, 2024, was $15.6 million compared to a net loss of $8.8 million for the same period in 2023. Net loss for the full year ended December 31, 2024 was $61.9 million compared to a net loss of $32.6 million for the same period in 2023. About MBX Biosciences MBX Biosciences is a biopharmaceutical company focused on the discovery and development of novel precision peptide therapies based on its proprietary PEP™ platform, for the treatment of endocrine and metabolic disorders. The Company is advancing a pipeline of novel candidates for endocrine and metabolic disorders with clinically validated targets, established endpoints for regulatory approval, significant unmet medical needs and large potential market opportunities. The Company’s pipeline includes its lead product candidate canvuparatide (MBX 2109), in Phase 2 development for the treatment of chronic hypoparathyroidism (HP); MBX 1416, in Phase 1 development for the treatment of post-bariatric hypoglycemia (PBH); and an obesity portfolio that includes MBX 4291, with an IND filing anticipated in Q2 2025, as well as multiple discovery and pre-clinical candidates in development for the treatment of obesity. The Company is based in Carmel, Indiana. To learn more, please visit the Company website at www.mbxbio.com and follow it on LinkedIn. About MBX’s Proprietary Precision Endocrine Peptide (PEP™) Platform MBX was founded by global leaders with a transformative approach to peptide drug design and development. Leveraging this expertise, the Company designed its proprietary Precision Endocrine Peptide™ (PEP™) platform to overcome the key limitations of unmodified and modified peptide therapies and to improve clinical outcomes and simplify disease management for patients. PEPs are selectively engineered to have optimized pharmaceutical properties, including extended time-action profiles and consistent drug concentrations with low peak-to-trough concentration ratios, consistent exposure to target tissues, and less frequent dosing. Forward-Looking Statements This press release contains “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934, each as amended. The words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “would” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. These forward-looking statements include, but are not limited to, express or implied statements regarding: MBX Biosciences’ expectations regarding the Phase 2 Avail™ trial of canvuparatide, including enrollment and the timing of topline results; statements related to the potential for canvuparatide to be a once-weekly PTH replacement therapy; the expected timing for the Phase 2 trial for MBX 1416 and statements related to an end-of-phase 1 meeting with the FDA; statements related to the ability of MBX 1416 to be a treatment of PBH; the expected timing of the IND filing for MBX 4291 and initiation of a Phase 1 trial thereafter; statements related to the contribution of leadership; and expectations regarding MBX Biosciences’ uses of capital, expenses and financial results, including the anticipated cash runway timing. Forward looking statements are based on management’s current expectations and are subject to risks and uncertainties that could negatively affect MBX Biosciences’ business, operating results, financial condition and stock value. Factors that could cause actual results to differ materially from those currently anticipated include: risks relating to the Company’s research and development activities; MBX Biosciences’ ability to execute on its strategy including obtaining the requisite regulatory approvals on the expected timeline, if at all; uncertainties relating to preclinical and clinical development activities; the Company’s dependence on third parties to conduct clinical trials, manufacture its product candidates and develop and commercialize its product candidates, if approved; MBX Biosciences’ ability to attract, integrate and retain key personnel; risks related to the Company’s financial condition and need for substantial additional funds in order to complete development activities and commercialize a product candidate, if approved; risks related to regulatory developments and approval processes of the U.S. Food and Drug Administration and comparable foreign regulatory authorities; risks related to establishing and maintaining MBX Biosciences’ intellectual property protections; and risks related to the competitive landscape for MBX Biosciences’ product candidates; as well as other risks described in “Risk Factors,” in MBX Biosciences’ Quarterly Report on Form 10-Q for the nine months ended September 30, 2024 filed with the Securities and Exchange Commission (SEC), its Annual Report on Form 10-K for the year ended December 31, 2024 filed with the SEC, as well as subsequent filings with the SEC. MBX Biosciences expressly disclaims any obligation or undertaking to release publicly any updates or revisions to any forward-looking statements contained herein to reflect any change in its expectations or any changes in events, conditions or circumstances on which any such statement is based, except as required by law, and claims the protection of the safe harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995. MBX uses and intends to continue to use its Investor Relations website as a means of disclosing material nonpublic information and for complying with its disclosure obligations under Regulation FD. Accordingly, investors should monitor the Company's Investor Relations website, in addition to following the Company's press releases, SEC filings, public conference calls, presentations, and webcasts. Media Contact: Katie Beach Oltsik Inizio Evoke Comms [email protected] (937) 232-4889 Investor Contact: Jim DeNike MBX Biosciences [email protected]