This section highlights FDA-related milestones and regulatory updates for drugs developed by Prothena (PRTA).
Over the past two years, Prothena has reported clinical trial outcomes, regulatory submissions, approvals, and other FDA events for drugs and therapies such as
PRX004, Prasinezumab, and Birtamimab. For definitions of regulatory abbreviations such as NDA, BLA, or PDUFA, see the event status legend.
Select a button below to view the list of FDA events for that drug.
PRX004 FDA Regulatory Events
PRX004 is a drug developed by Prothena for the following indication: ATTR amyloidosis.
This drug is under review by the U.S. Food and Drug Administration (FDA).
Below is a timeline of key regulatory milestones for this therapy.
- Drug:
- PRX004
- Announced Date:
- April 27, 2026
- Indication:
- ATTR amyloidosis
Announcement
Prothena Corporation plc announced that the U.S. Food and Drug Administration (FDA) has granted Fast Track Designation to coramitug, a potential best-in-class amyloid depleter antibody currently in Phase 3 development for the treatment of ATTR amyloidosis with cardiomyopathy (ATTR-CM).
AI Summary
Prothena Corporation announced that the U.S. Food and Drug Administration has granted Fast Track Designation to coramitug, a potential best-in-class amyloid-depleting antibody currently in Phase 3 development for ATTR amyloidosis with cardiomyopathy (ATTR-CM). The designation is meant to help speed the development and review of treatments that address unmet medical needs.
ATTR-CM is a progressive heart disease caused by transthyretin protein forming amyloid deposits in the heart. Existing therapies may slow disease progression but do not clear those deposits. Coramitug is a humanized monoclonal antibody that targets misfolded transthyretin and is designed to promote clearance of amyloid through antibody-mediated phagocytosis, potentially removing harmful deposits.
Novo Nordisk holds worldwide rights to coramitug under an earlier agreement with Prothena. Under that deal, Prothena may receive up to $1.2 billion tied to development and sales milestones, with $150 million received to date. Prothena’s CEO said the Fast Track designation underscores commitment to advancing coramitug for patients with ATTR-CM.
Read Announcement- Drug:
- PRX004
- Announced Date:
- November 11, 2025
- Indication:
- ATTR amyloidosis
Announcement
Prothena Corporation plc announced the publication of Phase 2 clinical trial data for coramitug (formerly PRX004), a potential first-in-class amyloid depleter antibody, for the treatment of ATTR amyloidosis with cardiomyopathy (ATTR-CM), in the American Heart Association's journal, Circulation.
AI Summary
Prothena announced that Phase 2 clinical trial data for coramitug (formerly PRX004) were published in the American Heart Association journal Circulation following a late‑breaking presentation at the AHA Scientific Sessions on November 10, 2025. The randomized, multicenter, double‑blind, placebo‑controlled study evaluated coramitug as a potential first‑in‑class amyloid‑depleting antibody for transthyretin amyloid cardiomyopathy (ATTR‑CM). The published results showed safety and biomarker effects that supported continued development.
Novo Nordisk has launched the Phase 3 CLEOPATTRA trial to test coramitug versus placebo on cardiovascular outcomes in patients with ATTR‑CM. Coramitug is designed to remove deposited amyloid and circulating non‑native TTR while leaving the normal TTR tetramer intact. This depleter mechanism could improve organ function and might be used alone or with existing therapies. After acquiring Prothena’s ATTR program, Novo’s progress in Phase 3 also affects potential milestone payments to Prothena.
Read Announcement
Prasinezumab FDA Regulatory Events
Prasinezumab is a drug developed by Prothena for the following indication: Parkinson's disease.
This drug is under review by the U.S. Food and Drug Administration (FDA).
Below is a timeline of key regulatory milestones for this therapy.
- Drug:
- Prasinezumab
- Announced Date:
- June 16, 2025
- Indication:
- Parkinson's disease
Announcement
Prothena Corporation plc announced partner Roche will advance prasinezumab, an investigational anti-alpha-synuclein antibody, into Phase III development in early-stage Parkinson's disease.
AI Summary
Prothena Corporation plc announced that partner Roche will move forward with advancing prasinezumab into Phase III development for early-stage Parkinson’s disease. Prasinezumab is an investigational antibody that targets aggregated alpha-synuclein—a protein believed to drive the progression of Parkinson’s. Data from the Phase IIb PADOVA study, along with ongoing open-label extension studies, showed that prasinezumab may provide additional benefits on top of current symptomatic treatments. The studies noted promising trends, including a potential delay in motor progression and early signs of impacting the underlying disease biology. This development represents an important step toward creating the first disease-modifying treatment option for Parkinson’s, a condition that affects millions worldwide and has high unmet medical needs. By progressing to Phase III trials, this partnership hopes to further explore prasinezumab’s potential in slowing down the progression of Parkinson’s disease.
Read Announcement- Drug:
- Prasinezumab
- Announced Date:
- December 19, 2024
- Indication:
- Parkinson's disease
Announcement
Prothena Corporation plc announced results from the Phase IIb PADOVA study conducted by partner Roche investigating prasinezumab in 586 people with early-stage Parkinson's disease, treated for a minimum of 18 months while on stable symptomatic treatment.
AI Summary
Prothena Corporation plc announced promising results from the Phase IIb PADOVA study conducted by Roche for prasinezumab in 586 early-stage Parkinson's patients. Participants were treated for at least 18 months while continuing stable symptomatic therapy. The study showed a numerical delay in motor progression and positive trends across several secondary and exploratory endpoints. Notably, the primary endpoint—time to confirmed motor progression—demonstrated a trend favoring prasinezumab, especially in the subgroup of patients already receiving levodopa, indicating a potential clinical benefit in slowing disease advancement.
The treatment was well tolerated with no new safety concerns observed. Roche plans to further evaluate the data and collaborate with health authorities to determine the next steps for prasinezumab’s development as a potential disease-modifying therapy for Parkinson’s disease.
Read Announcement
Birtamimab FDA Regulatory Events
Birtamimab is a drug developed by Prothena for the following indication: AL Amyloidosis.
This drug is under review by the U.S. Food and Drug Administration (FDA).
Below is a timeline of key regulatory milestones for this therapy.
- Drug:
- Birtamimab
- Announced Date:
- May 23, 2025
- Indication:
- AL Amyloidosis
Announcement
Prothena Corporation plc announced the Phase 3 AFFIRM-AL clinical trial evaluating birtamimab in patients with AL amyloidosis did not meet its primary endpoint (HR=0.915, p-value=0.7680).
AI Summary
Prothena Corporation plc announced that the Phase 3 AFFIRM-AL clinical trial evaluating birtamimab in patients with AL amyloidosis did not meet its primary endpoint. The trial showed a hazard ratio of 0.915 with a p-value of 0.7680, meaning that birtamimab did not improve time to all-cause mortality compared to standard care. Secondary endpoints, including the 6-minute walk test and a physical health score, were also not met. As a result, Prothena will discontinue the development of birtamimab and halt the open-label extension of the AFFIRM-AL trial.
The decision to stop the program is part of a broader plan to decrease ongoing operating expenses and reduce the company’s organizational size. Prothena plans to provide further updates in June regarding its efforts to adjust spending and explore additional business options.
Read Announcement
