--- title: "Prothena Corporation (PRTA) stock: news and investor profile" url: "https://aibio.space/companies/prothena/" publisher: "aibio.space (Biotech Investor Relations News)" summary: "Prothena Corporation plc (NASDAQ: PRTA), Ireland. The directory classifies it as Biotechnology." --- PRTA Prothena Corporation plc NASDAQ · Ireland # Prothena Corporation (PRTA) news Distress · 2026-10-29 ## [Bristol Myers Squibb drops Prothena's PRX019, ending up to $617.5 million in milestones](https://aibio.space/news/bristol-myers-squibb-drops-prothenas-prx019-ending-up-617-5-million/) Bristol Myers Squibb will end its PRX019 license on January 28, 2027, dropping up to $617.5 million in milestones it could have owed. The 8-K cites an internal strategic review and gives no further reason. ## Latest Prothena Corporation news 1. 2025-06-18 Distress [Prothena cuts workforce by about 63% after ending birtamimab development](https://aibio.space/news/prothena-cuts-workforce-about-63-percent-after-ending-birtamimab/) Prothena expects $16 to $20 million in severance and related charges from the workforce reduction. Its Chief Regulatory Officer and Chief People Officer will leave effective August 1, 2025. 2. 2025-06-18 Distress [Prothena cuts about 63% of workforce after ending birtamimab, expects $16 to $20 million in charges](https://aibio.space/news/prothena-cuts-about-63-percent-workforce-after-ending-birtamimab/) Prothena will cut about 63% of its workforce after ending birtamimab, and expects $16 to $20 million in charges, mostly cash. The 8-K gives no headcount, cash balance or savings figure. ## Prothena Corporation at a glance - **Ticker**: PRTA - **Listing**: NASDAQ - **Country**: Ireland - **Cash, Jun 30, 2026**: $288.2 million ### Related companies - [Malin Corporation](https://aibio.space/companies/malin/) EURONEXT: MLC - [Cosmo](https://aibio.space/companies/cosmo-n-v/) SIX: CMHC - [GH Research](https://aibio.space/companies/gh-research/) NASDAQ: GHRS - [Alkermes](https://aibio.space/companies/alkermes/) NASDAQ: ALKS - [Jazz Pharmaceuticals](https://aibio.space/companies/jazz-pharmaceuticals/) NASDAQ: JAZZ - [Amarin Corporation](https://aibio.space/companies/amarin/) NASDAQ: AMRN ### Also on NASDAQ - [Psyence Biomedical](https://aibio.space/companies/psyence-biomedical/) PBM - [MBX Biosciences](https://aibio.space/companies/mbx-biosciences/) MBX - [Monopar Therapeutics](https://aibio.space/companies/monopar-therapeutics/) MNPR - [ALIGN TECHNOLOGY INC](https://aibio.space/companies/align-technology/) ALGN - [Bioventus](https://aibio.space/companies/bioventus/) BVS - [ProQR Therapeutics](https://aibio.space/companies/proqr-therapeutics-n-v/) PRQR ## What Prothena Corporation does Prothena is a late-stage clinical biotechnology company with expertise in protein dysregulation, aiming to address neurodegenerative and rare peripheral amyloid diseases. Its pipeline includes wholly-owned and partnered programs for Parkinson's disease, ATTR amyloidosis with cardiomyopathy, Alzheimer's disease and amyotrophic lateral sclerosis (ALS). Its active clinical programs are all partnered with large pharmaceutical companies: prasinezumab, in the Phase 3 PARAISO trial for early Parkinson's disease with Roche; coramitug, in the Phase 3 CLEOPATTRA trial for ATTR-CM with Novo Nordisk; BMS-986446, in the Phase 2 TargetTau-1 trial for early Alzheimer's disease with Bristol Myers Squibb; and PRX019, in a Phase 1 trial under a global partnership with Bristol Myers Squibb. Its proprietary CYTOPE technology is designed to target intracellular disease pathways in the brain and periphery. Prothena is also conducting preclinical work on PRX012, a wholly-owned anti-Abeta antibody for Alzheimer's disease, combined with a transferrin receptor technology. | Product or program | What it is | Stage | |---|---|---| | prasinezumab | Parkinson's disease, partnered with Roche | Phase 3 | | coramitug | ATTR cardiomyopathy, partnered with Novo Nordisk | Phase 3 | | BMS-986446 | Early Alzheimer's disease, partnered with Bristol Myers Squibb | Phase 2 | | PRX019 | Partnered with Bristol Myers Squibb in a global partnership | Phase 1 | | CYTOPE technology | Targets intracellular disease pathways in the brain and periphery | | | PRX012 | Wholly-owned anti-Abeta antibody for Alzheimer's disease | preclinical | Summarised from the company's [10-K filed Feb 27, 2026](https://www.sec.gov/Archives/edgar/data/1559053/000155905326000008/prta-20251231.htm). ## Prothena Corporation annual financials | Line | FY2025 | FY2024 | |---|---|---| | Research and development | [$134.9 million](https://www.sec.gov/Archives/edgar/data/1559053/000155905326000008/) | [$222.5 million](https://www.sec.gov/Archives/edgar/data/1559053/000155905326000008/) | | Net income (loss) | [-$244.1 million](https://www.sec.gov/Archives/edgar/data/1559053/000155905326000008/) | [-$122.3 million](https://www.sec.gov/Archives/edgar/data/1559053/000155905326000008/) | | Cash from operations | [-$163.6 million](https://www.sec.gov/Archives/edgar/data/1559053/000155905326000008/) | [-$150.1 million](https://www.sec.gov/Archives/edgar/data/1559053/000155905326000008/) | | Cash and equivalents | [$307.5 million](https://www.sec.gov/Archives/edgar/data/1559053/000155905326000022/) | [$471.4 million](https://www.sec.gov/Archives/edgar/data/1559053/000155905326000008/) | Latest balance sheet, Jun 30, 2026 (10-Q): cash and equivalents $288.2 million. Figures as reported to the SEC in XBRL; each one links to its filing. Not adjusted, not investment advice. ## Questions about Prothena Corporation What is the ticker symbol of Prothena Corporation? Prothena Corporation plc trades under the ticker PRTA on NASDAQ. Where is Prothena Corporation listed? Prothena Corporation plc is listed on NASDAQ. Our directory also records these other listings: GETTEX:0PT; LSE:0Y3M; LSX:A1KAVV. What is the SEC CIK of Prothena Corporation? The SEC Central Index Key (CIK) for Prothena Corporation plc is 1559053. Its filings are on SEC EDGAR. How many shares does Prothena Corporation have outstanding? 51,336,974 shares as of 2026-07-30, per the cover page of its 10-Q filed 2026-08-06. Which country or territory is Prothena Corporation listed under? Our directory records Prothena Corporation plc under Ireland. What does Prothena Corporation do? Our directory classifies Prothena Corporation plc as: Biotechnology. This is a directory classification, not a description of the pipeline. What is the ISIN of Prothena Corporation? The ISIN recorded for Prothena Corporation plc is IE00B91XRN20. Does aibio.space cover Prothena Corporation? aibio.space lists Prothena Corporation plc among 2,820 public biotech companies and publishes its news here as stories appear. Where is Prothena Corporation incorporated? SEC records list its state or country of incorporation as L2. What does Prothena Corporation develop? Prothena is a late-stage clinical biotechnology company with expertise in protein dysregulation, aiming to address neurodegenerative and rare peripheral amyloid diseases. Its pipeline includes wholly-owned and partnered programs for Parkinson's disease, ATTR amyloidosis with cardiomyopathy, Alzheimer's disease and amyotrophic lateral sclerosis (ALS). What is prasinezumab from Prothena Corporation? prasinezumab: Parkinson's disease, partnered with Roche Stage: Phase 3. What is coramitug from Prothena Corporation? coramitug: ATTR cardiomyopathy, partnered with Novo Nordisk Stage: Phase 3. Is Prothena Corporation profitable? Prothena Corporation plc reported a net loss of $244.1 million for the fiscal year ended Dec 31, 2025, and used $163.6 million of cash in operations, per its annual report to the SEC. How much does Prothena Corporation spend on research and development? $134.9 million in the fiscal year ended Dec 31, 2025, per its annual report. How much cash does Prothena Corporation have? $288.2 million in cash at Jun 30, 2026, per its 10-Q. ## Investor discussion: Prothena Corporation Members talk about Prothena Corporation (PRTA). Reader posts, not aibio.space reporting, and not investment advice. Rules 1. **Securities violations are strictly forbidden.** No market manipulation, no pump-and-dump, no false or misleading statements, and no inside information. 2. **Say whether you hold the stock.** Every post states long, short or no position. 3. **No paid or sponsored posts.** Do not post for anyone who pays or rewards you. 4. **No buy or sell calls and no price targets.** 5. **No accusations of crime or fraud against named people** unless you link a court filing or a regulator's release that makes them. 6. **No personal details and no spam.** No links at all for your first 7 days as a member. Posts that break the rules may be deleted without notice, and the account restricted or closed. See the [terms](https://aibio.space/terms/#discussion) and the [privacy policy](https://aibio.space/privacy/#discussion). ## Capital-markets timeline Financings, listing notices, splits, legal actions and other investor events at Prothena Corporation, newest first. Each line links the filing it comes from. 1. 2026-10-29 Distress Reported the end of a material agreement. SEC Form 8-K (Items 1.02,9.01). [Source](https://www.sec.gov/Archives/edgar/data/1559053/000155905326000026/prta-20261028.htm) 2. 2025-06-18 Distress Reported a restructuring, a workforce reduction or a review of strategic alternatives. SEC Form 8-K (Items 2.05,5.02). [Source](https://www.sec.gov/Archives/edgar/data/1559053/000119312525142725/d945146d8k.htm) ## Stock chart Price chart and quote supplied by TradingView, delayed as the exchange requires. It loads only if you choose to show it. Information only, not investment advice. [Open NASDAQ:PRTA on TradingView](https://www.tradingview.com/symbols/NASDAQ-PRTA/). ## SEC filings and registration - **SEC name**: Prothena Corp Public Ltd Co - **CIK**: 1559053 - **Industry (SIC)**: Pharmaceutical Preparations (2834) - **US tickers**: PRTA (Nasdaq) - **State or country of incorporation**: L2 - **Fiscal year ends**: December 31 - **Filer category**: Accelerated filer - **Business address**: 77 SIR JOHN ROGERSON'S QUAY, BLOCK C, DUBLIN 2, Ireland, D02 VK60 - **Phone**: 011-353-1-236-2500 - **Shares outstanding**: 51,336,974 as of 2026-07-30 (10-Q filed 2026-08-06) - **Former names**: Prothena Corp plc; Neotope Corp Ltd ### Recent filings (8-K and 6-K are the company's own announcements) - [8-K](https://www.sec.gov/Archives/edgar/data/1559053/000155905326000024/prta-20261002.htm) filed 2026-10-02 - [10-Q](https://www.sec.gov/Archives/edgar/data/1559053/000155905326000022/prta-20260630.htm) filed 2026-08-06 - [8-K](https://www.sec.gov/Archives/edgar/data/1559053/000155905326000021/prta-20260806.htm) filed 2026-08-06 - [8-K](https://www.sec.gov/Archives/edgar/data/1559053/000119312526226968/d48146d8k.htm) filed 2026-05-15 - [10-Q](https://www.sec.gov/Archives/edgar/data/1559053/000155905326000017/prta-20260331.htm) filed 2026-05-07 - [8-K](https://www.sec.gov/Archives/edgar/data/1559053/000155905326000016/prta-20260507.htm) filed 2026-05-07 - [DEF 14A](https://www.sec.gov/Archives/edgar/data/1559053/000155905326000012/prta-20260327.htm) filed 2026-03-27 - [8-K](https://www.sec.gov/Archives/edgar/data/1559053/000155905326000009/prta-20260227.htm) filed 2026-02-27 Source: [SEC EDGAR](https://www.sec.gov/cgi-bin/browse-edgar?action=getcompany&CIK=0001559053), retrieved October 23, 2026. Shares outstanding is the cover-page figure from the latest periodic report. The SEC does not publish share prices. ## Listing details Prothena Corporation plc is a public biotech or pharmaceutical company listed on NASDAQ under the ticker PRTA, recorded under Ireland. The directory classifies it as Biotechnology. aibio.space tracks 2,820 public biotech companies worldwide and publishes investor news on them. - **Company**: Prothena Corporation plc - **Ticker**: PRTA - **Listing**: NASDAQ - **Country or territory**: Ireland - **Business scope**: Biotechnology - **ISIN**: IE00B91XRN20 - **Other listed symbols**: GETTEX:0PT; LSE:0Y3M; LSX:A1KAVV - **Last quote in directory**: 2026-10-21 - **Directory source**: [Listing page](https://www.tradingview.com/symbols/NASDAQ-PRTA/) Listing facts come from our company directory, researched on October 22, 2026. A listing record does not certify that a security currently trades. [Tell us about a change](https://aibio.space/reputation/#update). 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