Welcome to our dedicated page for Prothena news (Ticker: PRTA), a resource for investors and traders seeking the latest updates and insights on Prothena stock.
Prothena Corporation plc develops investigational therapeutics built on protein dysregulation expertise for neurodegenerative and rare peripheral amyloid diseases. Company news commonly covers clinical and partner updates for programs such as prasinezumab in Parkinson’s disease, coramitug in ATTR amyloidosis with cardiomyopathy, BMS-986446 in Alzheimer’s disease, PRX019, and CYTOPE-based research.
Updates also include financial results, cash guidance, collaboration revenue and milestone payments from strategic partners, regulatory designations, share repurchase activity, shareholder capital actions, and leadership or governance changes.
Prothena (NASDAQ:PRTA) reported second quarter 2026 net loss of $18.6 million on total revenue of $1.0 million, versus a $125.8 million loss and $4.4 million revenue in Q2 2025. For the first six months of 2026, the company recorded net income of $14.1 million and total revenue of $52.1 million, driven mainly by a $50.0 million milestone payment from Novo Nordisk for the Phase 3 coramitug program.
R&D and G&A expenses declined sharply year over year, and restructuring costs fell to $2.4 million in Q2 2026. Prothena ended June 30, 2026 with $289.1 million in cash, cash equivalents and restricted cash, no debt, and had repurchased 2.24 million shares for $22.3 million under its up to $100 million buyback. Updated 2026 guidance calls for $18–$23 million net cash used and year-end cash around $259 million (midpoint), reflecting cash deployed for share repurchases. Clinical highlights include published Phase 2b PADOVA data for prasinezumab in early Parkinson’s disease, ongoing Phase 3 trials for prasinezumab and coramitug, a Phase 2 trial for moponetug in Alzheimer’s disease, and multiple CYTOPE-based preclinical and research collaborations.
Prothena (NASDAQ:PRTA) announced it will report its second quarter and first six months 2026 financial results on Thursday, August 6, 2026, after the close of U.S. financial markets. The company also said it will not hold a conference call in conjunction with this earnings release, consistent with its past practice.
Prothena (NASDAQ:PRTA) reported Q1 2026 results and business highlights on May 7, 2026. Key items: net income $32.7M, revenue $51.1M (includes $50M Novo Nordisk milestone), cash $330.3M at quarter-end, and updated 2026 net cash use guidance to $18–$23M.
Pipeline and corporate actions: Novo Nordisk coramitug Fast Track and $50M payment, Roche prasinezumab Phase 2/3 updates, completed PRX019 Phase 1, potential $55M BMS milestone, and a $100M share repurchase authorization (≈$7.3M repurchased through 3/31/26).
Summary not available.
Prothena (NASDAQ:PRTA) announced the U.S. FDA has granted Fast Track Designation to coramitug (PRX004), an antibody in Phase 3 development for ATTR amyloidosis with cardiomyopathy (ATTR-CM). Coramitug is being evaluated by Novo Nordisk in the ~1,280-participant CLEOPATTRA trial with primary completion expected in 2029.
Under a July 2021 agreement, Novo Nordisk holds worldwide rights to the program; Prothena is eligible for up to $1.2 billion in payments and has earned $150 million to date.
Prothena (NASDAQ:PRTA) announced leadership updates effective April 10, 2026: Annie Kingston is promoted to Chief Strategy Officer effective immediately, and Michael Isaacs is promoted to General Counsel and Corporate Secretary effective following Mike Malecek’s departure in June 2026. Both will report to Gene Kinney, Ph.D.
The company said Kingston will lead growth strategy and Isaacs will oversee corporate legal functions while Tran Nguyen remains Chief Financial Officer.
Prothena (NASDAQ:PRTA) partners presented clinical updates at AD/PD 2026 on prasinezumab (Roche) for Parkinson’s disease and BMS-986446 (Bristol Myers Squibb) for Alzheimer’s disease.
Key takeaways: PASADENA OLE outcomes suggested an estimated ~2 years “time saved” versus model predictions at five years; PADOVA OLE showed sustained slowing of progression and supportive neuromelanin/iron MRI biomarker signals. BMS reported single-dose safety, dose-proportional exposure and no anti-drug antibodies in healthy participants, including Japanese ethnicity.
Prothena (NASDAQ:PRTA) announced it earned a $50 million clinical milestone payment from Novo Nordisk after reaching a prespecified enrollment target in the Phase 3 CLEOPATTRA trial of coramitug (formerly PRX004) for ATTR amyloidosis with cardiomyopathy.
Prothena has now earned $150 million of a possible $1.2 billion in milestone payments under the 2021 asset sale; CLEOPATTRA targets ~1,280 participants with primary completion expected in 2029.
Prothena (NASDAQ:PRTA) authorized a share repurchase plan to buy up to $100.0 million of its ordinary shares through December 31, 2026.
The company reported $308.4 million in cash, cash equivalents and restricted cash and no debt as of December 31, 2025, and expects to end 2026 with about $255 million excluding repurchases and potential milestones. Prothena noted up to $105 million of potential 2026 clinical milestone payments from partners. Repurchases may occur in open market transactions, under Rule 10b-18, or via 10b5-1 plans, and may be suspended or discontinued at the company’s discretion.
Prothena (NASDAQ:PRTA) reported Q4 2025 net loss of $21.6M and full-year net loss of $244.1M. Quarter-end cash was $308.4M. 2026 guidance: net cash used in operations and investing of $50–55M and year-end cash around $255M (midpoint). Partners Roche, Novo Nordisk and Bristol Myers Squibb advanced Phase 3 or Phase 2 programs with primary completions expected in 2029 and potential partner milestones up to $105M in 2026.
Shareholders approved a capital reduction to enable a potential 2026 share redemption program; company expects to discuss results on a Feb 19, 2026 conference call.