PROTHENA CORP PUBLIC LTD ( PRTA )

Prothena Discusses Pipeline Progress and Upcoming Milestones

PRTA

New Projects/Investments

Guidance Update

Share Buyback

Prothena Corporation has two Phase 3 programs: prasunezumab for early Parkinson's disease partnered with Roche, and coramitug for ATTR cardiomyopathy partnered with Novo. Novo has initiated its Phase 3, and Roche is expected to initiate its Phase 3 in the fourth quarter.
The company anticipates earning up to $105 million in clinical milestones in 2026, related to coramitug reaching a certain number of enrolled patients and a decision on PRX019 from Bristol.
A share repurchase program for 2026 was approved following a successful Extraordinary General Meeting (EGM).
Preclinical data for the transferrin PRX012 molecule for Alzheimer's disease is expected in 2026, and data for the Phase 2 MTBR Tau program (BMS-986446) is anticipated in 2027.

Dec 4, 2025, 3:50 PM

Prothena Highlights Late-Stage Pipeline, Upcoming Milestones, and 2026 Share Repurchase Plan

PRTA

New Projects/Investments

Share Buyback

Guidance Update

Prothena is advancing a robust pipeline, including two late-stage Phase 3 programs: Prasinezumab for early Parkinson's (partnered with Roche, Phase 3 initiation in Q4) and Coramitug for ATTR cardiomyopathy (partnered with Novo, Phase 3 initiated).
The company anticipates earning $105 million in clinical milestones from Coramitug and PRX019 by the end of 2026.
Significant remaining milestone payments include $620 million for Prasinezumab , $1.13 billion for Coramitug (tax-free) , $562.5 million for PRX005 , and $617.5 million for PRX019 , along with tiered royalties for all partnered programs.
Prothena plans to announce a share repurchase program in 2026 around its Q4 2025 announcement.
The company is also actively seeking partnerships for unpartnered programs and its CyTOPE technology in 2026.

Dec 3, 2025, 6:00 PM

Prothena Outlines Pipeline Strategy and 2026 Financial Focus

PRTA

New Projects/Investments

Share Buyback

Prothena is advancing two late-stage Phase 3 programs: Prasinezumab for early Parkinson's (partnered with Roche) and Coramitug for ATTR cardiomyopathy (partnered with Novo), both of which have initiated Phase 3 trials.
The company expects to achieve $105 million in clinical milestones in 2026 from its Coramitug and PRX019 programs.
Key partnership economics include $620 million remaining in milestones for Prasinezumab (Roche) and $1.13 billion remaining for Coramitug (Novo), with the latter being tax-free.
Prothena plans to announce a share repurchase program in 2026 and is actively seeking partners for unpartnered programs and its CyTOPE technology.

Dec 3, 2025, 6:00 PM

Prothena Highlights Phase 2 Coramitug Data Publication

PRTA

New Projects/Investments

M&A

Prothena announced the publication of Phase 2 clinical trial data for coramitug (formerly PRX004) in Circulation, the official journal of the American Heart Association (AHA).
Coramitug, a potential first-in-class amyloid depleter antibody for ATTR amyloidosis with cardiomyopathy (ATTR-CM), is being developed by Novo Nordisk, which recently initiated the Phase 3 CLEOPATTRA clinical trial.
Prothena is eligible to receive up to $1.2 billion from Novo Nordisk for the acquired ATTR amyloidosis business and pipeline, with $100 million already earned.
Prothena is eligible for an additional clinical milestone payment upon meeting prespecified enrollment criteria in the Phase 3 CLEOPATTRA trial.

Nov 11, 2025, 2:00 PM

Prothena Reports Q3 2025 Financial Results and Clinical Advancements

PRTA

Earnings

Guidance Update

Share Buyback

Prothena reported a net loss of $36.5 million on total revenue of $2.4 million for the third quarter of 2025.
As of September 30, 2025, the company held $331.7 million in cash, cash equivalents, and restricted cash.
Key clinical advancements include Roche's plan to initiate the Phase 3 PARAISO clinical trial for prasinezumab by year-end 2025 and Novo Nordisk's initiation of the Phase 3 CLEOPATTRA clinical trial for coramitug.
The company anticipates earning up to $105 million in clinical milestone payments by the end of 2026 and is seeking shareholder approval for a share capital reduction to support a potential share redemption program in 2026.

Nov 6, 2025, 9:09 PM

8-K

Prothena Reports Q3 2025 Financial Results and Business Highlights

PRTA

Earnings

Guidance Update

Share Buyback

Prothena reported a net loss of $36.5 million and total revenue of $2.4 million for the third quarter of 2025, with $331.7 million in cash, cash equivalents, and restricted cash as of September 30, 2025.
The company expects full-year 2025 net cash used in operating and investing activities to be between $170 million and $178 million, projecting an approximate $298 million cash position by year-end.
Key clinical advancements include Roche's plan to initiate the Phase 3 PARAISO trial for prasinezumab by year-end 2025, Novo Nordisk's initiation of the Phase 3 CLEOPATTRA trial for coramitug, and Bristol Myers Squibb receiving Fast Track designation for BMS-986446 for Alzheimer's disease.
An Extraordinary General Meeting is scheduled for November 19, 2025, to approve a capital reduction, which could enable a share redemption program in 2026.

Nov 6, 2025, 9:05 PM

Taysha Gene Therapies Reports Q3 2025 Results and TSHA-102 Program Updates

PRTA

Earnings

Guidance Update

New Projects/Investments

Taysha Gene Therapies reported a net loss of $32.7 million, or $0.09 per share, for the three months ended September 30, 2025.
As of September 30, 2025, the company held $297.3 million in cash and cash equivalents, which is expected to support planned operating expenses and capital requirements into 2028.
The FDA granted Breakthrough Therapy designation to TSHA-102 for the treatment of Rett syndrome, and Taysha finalized FDA alignment on the REVEAL pivotal trial protocol.
Dosing of the first patient in the REVEAL pivotal trial is scheduled for Q4 2025, and the company regained full unencumbered rights to the TSHA-102 Rett syndrome program in October 2025.

Nov 4, 2025, 12:00 PM

Prothena's Partner Bristol Myers Squibb Secures FDA Fast Track Designation for Alzheimer's Drug

PRTA

New Projects/Investments

Prothena Corporation plc announced that its partner, Bristol Myers Squibb, has received Fast Track Designation from the U.S. FDA for BMS-986446 (PRX005), an anti-MTBR-tau-targeting antibody for the treatment of early Alzheimer's disease.
This designation is intended to facilitate the development and expedite the review of the investigational drug, which is currently in Phase 2 development and fully enrolled.
BMS-986446 is being investigated as a potential disease-modifying therapy designed to slow or delay the progression of Alzheimer's disease by neutralizing the spread and promoting the clearance of pathological tau.
Prothena is eligible to receive additional regulatory and sales milestone payments of up to $562.5 million and tiered royalties on net sales from Bristol Myers Squibb under their global license agreement.

Oct 1, 2025, 8:45 PM

Prothena Announces Phase 1 ASCENT Clinical Program Results for PRX012

PRTA

New Projects/Investments

Prothena announced results from its Phase 1 ASCENT clinical program for PRX012, an anti-amyloid beta antibody for early symptomatic Alzheimer’s disease.
The program demonstrated dose- and time-dependent reductions in amyloid plaque, with the 400 mg dose achieving a mean reduction in amyloid PET to 27.47 centiloids (CL) at month 12.
However, PRX012 was associated with higher overall ARIA-E rates relative to FDA-approved anti-Aβ antibodies, making it less appropriate for the patients studied.
Prothena plans to explore potential partnership interest to advance PRX012 and its preclinical PRX012-TfR (transferrin receptor) antibody, which is being developed to potentially lower ARIA risk.

Aug 27, 2025, 8:05 PM

Earnings Transcripts

Quarterly earnings call transcripts for PROTHENA CORP PUBLIC LTD.

Q4 2024

Feb 20, 2025

Q4 2023

Feb 15, 2024

Q4 2022

Feb 23, 2023

Q4 2021

Feb 18, 2022

Q4 2020

Feb 11, 2021