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PRTA NASDAQ

Prothena Corporation plc
1W: -0.9% 1M: +1.3% 3M: -1.9% YTD: -8.7% 1Y: -13.8% 3Y: -81.2% 5Y: -86.7%
$8.81
+0.41 (+4.88%)
After Hours: $8.75 (-0.06, -0.68%)
Weekly Expected Move ±6.8%
$7 $8 $8 $9 $9
NASDAQ · Healthcare · Biotechnology · Tech Score Sell · Power 41 · $431.2M mcap · 44M float · 1.18% daily turnover · Short 70% of daily vol
Credit Risk of going bust: lower than 83% of companies Debt: 1.6% of company value Bonds: none of note held by US funds details ▾
If the stock fell to about $0.01 (down 99.9%), Prothena Corporation plc would be worth roughly what it owes.
Total debt $7.0M against a stock market value of $431.2M.
Distance to default 10.45 (Merton model): prices to 2026-10-26, balance sheet 2026-06-30, debt counted $3.0M (short-term plus half of long-term), stock volatility 47.4%; Altman Z'' 9.96. A ranking and a back-test, not a forecast.
US fund filings (SEC N-PORT) show under $25M of this company's bonds, so there is no bond page. Its debt may be bank loans or privately placed. How these are computed.
Smart Money Score
Moderate 50
Insider+$12.1M
Congress—
ETF Holdings—
Key Statistics
Market Cap$431.2M
52W Range7.73-11.8
Volume594,543
Avg Volume518,400
Beta-0.33
Dividend—
Analyst Ratings
20 Buy 6 Hold 2 Sell
Consensus Buy
Company Info
CEOGene G. Kinney
Employees67
SectorHealthcare
IndustryBiotechnology
IPO Date2012-12-20
77 Sir John Rogerson’s Quay
Dublin, DU D02 VK60
IE
353 1 236 2500
About Prothena Corporation plc

Prothena Corporation plc, a late-stage clinical biotechnology company, focuses on discovery and development of novel therapies to treat diseases caused by protein dysregulation. Its product pipeline includes Prasinezumab, an investigational humanized monoclonal antibody which is in Phase 3 clinical trial for the treatment of parkinson's disease and other synucleinopathies. The company also develops Coramitug, an investigational antibody, which is in Phase 3 clinical trial for the treatment of transthyretin amyloidosis; BMS-986446, an anti-tau antibody which is in Phase 2 clinical trial to treat Alzheimer's disease; PRX019, an investigational antibody which is in Phase 1 clinical trial for the treatment of neurodegenerative diseases; and PRX123, a Dual Aß-Tau Vaccine, which is in preclinical trial for treating Alzheimer's disease. In addition, it develops discovery- and late-preclinical-stage programs include TDP-43 CYTOPE for the treatment of amyotrophic lateral sclerosis; PRX012, a next-generation anti-Aß antibody which is in phase 1 clinical trial to treat Alzheimer's disease; and PRX012-TfR, a preclinical program for the treatment of Alzheimer's disease. It has a license, development, and commercialization agreement with F. Hoffmann-La Roche Ltd. and Hoffmann-La Roche Inc. to develop and commercialize antibodies that target a-synuclein, including prasinezumab; and master collaboration agreement with Bristol Myers Squibb to develop and commercialize antibodies targeting tau, TDP-43. Prothena Corporation plc was incorporated in 2012 and is based in Dublin, Ireland.

Recent Insider Trades

NameTypeSharesPriceDate
SCULLY WILLIAM P P-Purchase 50,000 $8.07 2026-10-23
SCULLY WILLIAM P P-Purchase 100,000 $8.19 2026-10-22
SCULLY WILLIAM P P-Purchase 10,000 $8.46 2026-10-14
SCULLY WILLIAM P P-Purchase 100,000 $8.35 2026-10-13
SCULLY WILLIAM P P-Purchase 90,000 $8.57 2026-10-08

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For informational purposes only. Not investment advice. Data sourced from SEC filings. Privacy Terms