17-Feb-2026
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Prothena to Report Fourth Quarter and Full Year 2025 Financial Results on February 19, 2026
Business Wire (Thu, 12-Feb 4:05 PM ET)
Prothena Announces Board of Directors Update
Business Wire (Fri, 12-Dec 4:05 PM ET)
Prothena Announces Poster Presentation on its TDP-43 CYTOPE Program at Neuroscience 2025
Business Wire (Wed, 19-Nov 4:05 PM ET)
Prothena Corp PLC is a clinical biotechnology company that focuses on protein dysregulation and a pipeline of investigational therapeutics with the potential to change the course of devastating neurodegenerative and rare and peripheral amyloid diseases. The company's clinical pipeline of antibody-based product candidates targets a range of indications, including Amyloid Light-chain (AL) amyloidosis (NEOD001), Parkinson's disease and other related synucleinopathies (PRX002), and inflammatory diseases, including ATTR amyloidosis [Coramitug (PRX004)], Alzheimer's disease (PRX123), Neurodegeneration (PRXPRX019), and Others.
Prothena PLC - trades on the NASDAQ stock market under the symbol PRTA.
As of February 17, 2026, PRTA stock price was flat at $8.96 with 343,720 million shares trading.
PRTA has a beta of 0.76, meaning it tends to be less sensitive to market movements. PRTA has a correlation of 0.04 to the broad based SPY ETF.
PRTA has a market cap of $482.29 million. This is considered a Small Cap stock.
Last quarter Prothena PLC - reported $2 million in Revenue and -$.68 earnings per share. This fell short of revenue expectation by $-11 million and missed earnings estimates by -$.12.
In the last 3 years, PRTA traded as high as $79.65 and as low as $4.32.
The top ETF exchange traded funds that PRTA belongs to (by Net Assets): XBI, IWM, VXF, IWN, IBB.
PRTA has underperformed the market in the last year with a return of -35.5%, while the SPY ETF gained +13.2%. In the last 3 month period, PRTA fell short of the market, returning -12.0%, while SPY returned +1.9%. However, in the most recent 2 weeks PRTA has outperformed the stock market by returning +1.7%, while SPY returned -1.3%.
PRTA support price is $8.61 and resistance is $9.32 (based on 1 day standard deviation move). This means that using the most recent 20 day stock volatility and applying a one standard deviation move around the stock's closing price, stastically there is a 67% probability that PRTA shares will trade within this expected range on the day.
