PRTA

ProthenaC

Nasdaq / Pharmaceuticals, Biotechnology & Life Sciences

At close

2026-06-02

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AI scenario view

RankAlpha Sentiment Codex

B+

Bull case

25%

Probability

Target price

$16.00

+74.1% vs current

Most likely

Base case

50%

Probability

Target price

$12.50

+36.0% vs current

B-

Bear case

25%

Probability

Target price

$7.25

-21.1% vs current

AI sentiment snapshot

Latest data as of 2026-04-17

AI commentary

Sentiment is mildly constructive but still monitoring-oriented. The March $50 million Novo milestone improved cash optics, while the more durable upside case still depends on partnered neurodegeneration programs that now stretch from a 2026 PRX019 decision to 2027-2029 clinical milestones and readouts; that keeps PRTA investable as a cash-backed option on partner execution, not as a clean near-term readout trade [#IR-2026-03-09] [#IR-2026-02-19] [#8-K-2026-02-27].

RankAlpha Sentiment Codex - 2026-04-17

Open full AI memo

Evidence flagged

peer set is too generic or lacks enough direct operating comparators; small-cap biotech peer set is too weak or includes unrelated comparators for a standard-conviction report

Impact

tentative

Confidence

AI events

2026-06-30catalystMarch coramitug milestone may keep improving cash-runway sentimentHigh impact

Prothena said on March 9 that it earned a $50 million milestone from Novo Nordisk after a prespecified enrollment target in the Phase 3 CLEOPATTRA trial, lifting total earned milestones from Novo to $150 million and improving near-term balance-sheet optics versus the February cash guide [#IR-2026-03-09] [#IR-2026-02-19].

2026-12-31eventBristol Myers Squibb PRX019 advancement decision remains the key 2026 binaryHigh impact

Management said it expects Bristol Myers Squibb to decide on the potential advancement of PRX019 in 2026, and Prothena said it could earn a clinical milestone by year-end 2026 if Bristol Myers decides to further develop the program; a positive decision would add external validation and incremental cash, while a delay or no-go would hurt sentiment [#IR-2026-02-19].

2027-06-30catalystPartnered neurodegeneration portfolio preserves long-duration option value beyond 2026High impact

Prothena said Roche started the Phase 3 PARAISO trial for prasinezumab in Parkinson's disease and Novo Nordisk started the Phase 3 CLEOPATTRA trial for coramitug in ATTR-CM, both with primary completions expected in 2029; the company also highlighted approximately $3 billion of aggregate future partnered milestones plus royalties, so continued partner execution is the clearest long-horizon value lever even if near-term readouts are limited [#IR-2026-02-19] [#8-K-2026-02-27].

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Recommendation

N/A

No formal recommendation provided.

Open AI Memo

As of 2026-04-17 • Updated nightlySource: Internal modelMethodology