Prothena Stock Price, News & Analysis

Prothena (NASDAQ:PRTA), a late-stage clinical biotechnology company focused on protein dysregulation therapeutics, has scheduled the release of its Q2 and H1 2025 financial results for Monday, August 4, 2025, following the U.S. market close. The company has indicated that it will maintain its standard practice of not holding a conference call to discuss the results.

Prothena Corporation (PRTA) announced a significant corporate restructuring, including a 63% workforce reduction to optimize operating costs. The restructuring follows several key milestones, including Roche's advancement of prasinezumab to Phase 3 for early-stage Parkinson's disease, upcoming PRX012 Phase 1 data for Alzheimer's, and various partnered programs with potential milestone payments. The company revised its 2025 financial guidance, projecting a net cash burn of $170-178 million and year-end cash position of approximately $298 million. The expected 2025 net loss is estimated at $240-248 million, including $36 million in non-cash share-based compensation and $45 million non-cash tax expense. The discontinuation of birtamimab development is expected to reduce annualized net cash burn by approximately $96 million.

Prothena (NASDAQ:PRTA) announced that its partner Roche will advance prasinezumab, a potential first-in-class anti-alpha-synuclein antibody, into Phase III development for early-stage Parkinson's disease. The decision follows data from the Phase IIb PADOVA study and open-label extensions from both PADOVA and Phase II PASADENA studies. While prasinezumab showed potential clinical efficacy in reducing motor progression at 104 weeks, it missed statistical significance in the primary endpoint. The drug demonstrated positive trends that appear sustained over longer treatment periods, and provided first biomarker evidence of impact on underlying disease biology. The ongoing PASADENA and PADOVA OLE studies are evaluating long-term safety and efficacy in over 750 early-stage Parkinson's patients.

Prothena (NASDAQ:PRTA) announced that its Phase 3 AFFIRM-AL clinical trial for birtamimab in AL amyloidosis patients failed to meet its primary endpoint of time to all-cause mortality (HR=0.915, p-value=0.7680). The trial also missed its secondary endpoints: 6-minute walk test distance and Short Form-36 Physical Component Score. As a result, Prothena will discontinue all birtamimab development, including the trial's open-label extension. While birtamimab demonstrated a consistent safety profile, the company plans substantial organizational downsizing and expense reductions, with detailed plans expected in June. Despite this setback, Prothena highlighted upcoming pipeline milestones, including Phase 1 ASCENT trial data for PRX012 in Alzheimer's disease (August), and partner updates from Roche (mid-2025), Novo Nordisk (2H25), and Bristol Myers Squibb (2026).

Prothena Corporation (PRTA) reported Q1 2025 financial results with a net loss of $60.2 million ($1.12 per share) and revenue of $2.8 million. The company ended Q1 with $418.8 million in cash and restricted cash. Key upcoming milestones include: 1. Topline results expected in Q2 2025 from Phase 3 AFFIRM-AL trial of birtamimab for AL amyloidosis 2. Multiple clinical readouts for PRX012 (Alzheimer's treatment) starting mid-2025 3. Phase 2b PADOVA trial results for prasinezumab in Parkinson's disease showed possible benefits 4. Phase 2 trial results for coramitug in ATTR-CM expected in 2H 2025 The company projects 2025 net cash use of $168-175 million in operating and investing activities, with an estimated year-end cash position of approximately $301 million.

Prothena Corporation (NASDAQ: PRTA), a late-stage clinical biotechnology company focused on protein dysregulation therapeutics, has scheduled the release of its first quarter 2025 financial results for Thursday, May 8, 2025, after U.S. financial markets close. The company has indicated that, following their usual practice, they will not hold a conference call to discuss the results.

Prothena (PRTA) reported its Q4 and full year 2024 financial results. The company recorded a net loss of $58.0 million in Q4 and $122.3 million for the full year 2024. Total revenue was $2.1 million in Q4 and $135.2 million for the full year 2024.

Key financial metrics include:

• Quarter-end cash position: $472.2 million
• Net cash used in operations: $47.8 million in Q4, $150.3 million for full year
• 2025 cash guidance: Expected net cash use of $168-175 million

Notable developments include:

• Topline results expected in Q2 2025 from Phase 3 AFFIRM-AL trial of birtamimab
• Multiple clinical readouts for PRX012 starting mid-2025
• Received $80 million from Bristol Myers Squibb for PRX019 license
• Phase 2b PADOVA study results for prasinezumab in Parkinson's disease

Prothena (NASDAQ:PRTA), a late-stage clinical biotechnology company focused on protein dysregulation expertise, has scheduled its fourth quarter and full year 2024 financial results announcement for Thursday, February 20, 2025, after U.S. market close. The company will host a live audio conference call at 4:30 PM ET on the same day.

The conference call will be accessible through the company's website at www.prothena.com under the Investors tab, with a replay available for at least 90 days. Participants can also join via dial-in at +1 (800) 715-9871 (U.S./Canada toll-free) or +1 (646) 307-1963 (international) using conference ID 9788564.

Prothena (NASDAQ:PRTA) announced that Oleg Nodelman will step down from the company's Board of Directors to focus on existing and new endeavors. Nodelman, who served on the board for five years since 2019, made significant contributions to the company's current strategy. Board Chair Daniel G. Welch acknowledged Nodelman's strategic impact and his role as a veteran biotechnology investor and advisor. Nodelman expressed confidence in the company's future, particularly noting the anticipated multiple clinical readouts across the portfolio in 2025.