NASDAQ:PRTA Prothena (PRTA) Stock Price, News & Analysis $9.59 -0.35 (-3.52%) Closing price 04:00 PM EasternExtended Trading$9.84 +0.25 (+2.60%) As of 07:55 PM Eastern Extended trading is trading that happens on electronic markets outside of regular trading hours. This is a fair market value extended hours price provided by Polygon.io. Learn more. Add Compare Share Share Stock Analysis Stock AnalysisAnalyst ForecastsChartCompetitorsEarningsFinancialsHeadlinesInsider TradesOptions ChainOwnershipSEC FilingsShort InterestTrendsBuy This Stock About Prothena Stock (NASDAQ:PRTA) 30 days 90 days 365 days Advanced Chart View Price History Chart DataSkip Price History Chart Get Prothena alerts:Sign Up Key Stats Today's Range$9.40▼$10.0450-Day Range$9.59▼$15.8152-Week Range$9.30▼$25.42Volume498,656 shsAverage Volume495,652 shsMarket Capitalization$516.20 millionP/E RatioN/ADividend YieldN/APrice Target$55.00Consensus RatingModerate Buy Company OverviewProthena Corporation plc, a late-stage clinical biotechnology company, focuses on discovery and development of novel therapies to treat diseases caused by protein dysregulation in the United States. The company is involved in developing birtamimab, an investigational humanized antibody that is in Phase III clinical trial for the treatment of AL amyloidosis; Prasinezumab, a humanized monoclonal antibody, for the treatment of Parkinson's disease and other related synucleinopathies which is in Phase IIb clinical trial; NNC6019 that is in Phase lI clinical trial for the treatment of ATTR amyloidosis; and BMS-986446 and PRX012, which is in Phase I clinical trial for the treatment of Alzheimer's disease. Its discovery and preclinical programs include PRX123, a dual Aß-Tau vaccine for the treatment and prevention of Alzheimer's disease; and PRX019 for the treatment of neurogenerative diseases, as well as TDP-43 for the treatment of amyotrophic lateral sclerosis. Prothena Corporation plc 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 a collaboration agreement with Bristol-Myers Squibb to develop and commercialize antibodies targeting tau, TDP-43. The company was incorporated in 2012 and is based in Dublin, Ireland.Read More… Remove Ads Prothena Stock Analysis - MarketRank™See Top-Rated MarketRank™ Stocks71st Percentile Overall ScorePRTA MarketRank™: Prothena scored higher than 71% of companies evaluated by MarketBeat, and ranked 301st out of 916 stocks in the medical sector. Scores are calculated by averaging available category scores, with extra weight given to analysis and valuation. Analyst's Opinion4.4 / 5Analyst RatingModerate Buy Consensus RatingProthena has received a consensus rating of Moderate Buy. The company's average rating score is 2.75, and is based on 6 buy ratings, 2 hold ratings, and no sell ratings.Amount of Analyst CoverageProthena has been the subject of 6 research reports in the past 90 days, demonstrating strong analyst interest in this stock.Read more about Prothena's stock forecast and price target. Earnings and Valuation1.3 / 5Proj. Earnings GrowthGrowing Earnings GrowthEarnings for Prothena are expected to grow in the coming year, from ($4.04) to ($3.33) per share.Price to Earnings Ratio vs. the MarketThe P/E ratio of Prothena is -4.17, which means that its earnings are negative and its P/E ratio cannot be compared to companies with positive earnings.Price to Earnings Ratio vs. SectorThe P/E ratio of Prothena is -4.17, which means that its earnings are negative and its P/E ratio cannot be compared to companies with positive earnings.Price to Book Value per Share RatioProthena has a P/B Ratio of 0.92. P/B Ratios below 1 indicate that a company could be undervalued with respect to its assets and liabilities.Read more about Prothena's valuation and earnings. Short Interest1.0 / 5Short Interest LevelBearish Percentage of Shares Shorted19.72% of the float of Prothena has been sold short.Short Interest Ratio / Days to CoverProthena has a short interest ratio ("days to cover") of 18.7, which indicates bearish sentiment.Change versus previous monthShort interest in Prothena has recently decreased by 4.56%, indicating that investor sentiment is improving. Dividend0.0 / 5Dividend StrengthN/A Dividend YieldProthena does not currently pay a dividend.Dividend GrowthProthena does not have a long track record of dividend growth. Sustainability and ESGN/AEnvironmental ScoreN/A Percentage of Shares Shorted19.72% of the float of Prothena has been sold short.Short Interest Ratio / Days to CoverProthena has a short interest ratio ("days to cover") of 18.7, which indicates bearish sentiment.Change versus previous monthShort interest in Prothena has recently decreased by 4.56%, indicating that investor sentiment is improving. News and Social Media3.4 / 5News Sentiment1.05 News SentimentProthena has a news sentiment score of 1.05. This score is calculated as an average of sentiment of articles about the company over the last seven days and ranges from 2 (good news) to -2 (bad news). This is a higher news sentiment than the 0.80 average news sentiment score of Medical companies.News Coverage This WeekMarketBeat has tracked 8 news articles for Prothena this week, compared to 3 articles on an average week.Search Interest3 people have searched for PRTA on MarketBeat in the last 30 days. This is an increase of 200% compared to the previous 30 days.MarketBeat FollowsOnly 1 people have added Prothena to their MarketBeat watchlist in the last 30 days. This is a decrease of -75% compared to the previous 30 days. Company Ownership3.3 / 5Insider TradingN/A Insider Buying vs. Insider SellingIn the past three months, Prothena insiders have not sold or bought any company stock.Percentage Held by Insiders28.20% of the stock of Prothena is held by insiders. A high percentage of insider ownership can be a sign of company health.Percentage Held by Institutions97.08% of the stock of Prothena is held by institutions. High institutional ownership can be a signal of strong market trust in this company.Read more about Prothena's insider trading history. Receive PRTA Stock News and Ratings via Email Sign-up to receive the latest news and ratings for Prothena and its competitors with MarketBeat's FREE daily newsletter. Email Address PRTA Stock News HeadlinesAnalysts Set Prothena Co. plc (NASDAQ:PRTA) Price Target at $55.00April 14 at 2:19 AM | americanbankingnews.comProthena Corporation: Multiple Failures Make It RiskyMarch 3, 2025 | seekingalpha.comTrump Treasure April 19Thanks to President Trump… A $900 investment across5 specific cryptos… Could gain 12,000% so quickly that, just 12 months later…April 15, 2025 | Paradigm Press (Ad)Prothena price target raised to $110 from $94 at Piper SandlerFebruary 26, 2025 | markets.businessinsider.comProthena Reports 2024 Financial Results and 2025 OutlookFebruary 22, 2025 | tipranks.comProthena’s Balanced Earnings Call Highlights Growth and ChallengesFebruary 22, 2025 | tipranks.comAnalysts Are Bullish on These Healthcare Stocks: Prothena (PRTA), Integer Holdings (ITGR)February 22, 2025 | markets.businessinsider.comProthena Reports Fourth Quarter and Full Year 2024 Financial Results, and Provides Financial Guidance and Business HighlightsFebruary 21, 2025 | uk.finance.yahoo.comSee More Headlines PRTA Stock Analysis - Frequently Asked Questions How have PRTA shares performed this year? Prothena's stock was trading at $13.85 at the beginning of the year. Since then, PRTA shares have decreased by 30.8% and is now trading at $9.59. View the best growth stocks for 2025 here. How were Prothena's earnings last quarter? Prothena Co. plc (NASDAQ:PRTA) released its quarterly earnings results on Thursday, February, 20th. The biotechnology company reported ($1.08) earnings per share for the quarter, missing analysts' consensus estimates of ($1.02) by $0.06. The biotechnology company earned $2.12 million during the quarter, compared to analysts' expectations of $7.53 million. Prothena had a negative net margin of 90.50% and a negative trailing twelve-month return on equity of 22.67%. Read the conference call transcript. Who are Prothena's major shareholders? Top institutional shareholders of Prothena include Hennion & Walsh Asset Management Inc. (0.14%), SG Americas Securities LLC (0.13%), Rhumbline Advisers (0.12%) and GAMMA Investing LLC (0.01%). Insiders that own company stock include Ecor1 Capital, Llc, Gene G Kinney, Tran Nguyen, Dennis J Selkoe, Richard T Collier, Lars Ekman, Michael J Malecek, Karin L Walker, Hideki Garren, Carol D Karp, Wagner M Zago and Brandon S Smith. View institutional ownership trends. How do I buy shares of Prothena? Shares of PRTA stock can be purchased through any online brokerage account. Popular online brokerages with access to the U.S. stock market include Charles Schwab, E*TRADE, Fidelity, and Vanguard Brokerage Services. What other stocks do shareholders of Prothena own? Based on aggregate information from My MarketBeat watchlists, some other companies that Prothena investors own include Voyager Therapeutics (VYGR), American Water Works (AWK), Humana (HUM), Waste Connections (WCN), The RMR Group (RMR), DiamondRock Hospitality (DRH) and AUO (AUOTY). Company Calendar Last Earnings2/20/2025Today4/15/2025Next Earnings (Estimated)5/06/2025Fiscal Year End12/31/2025Get Stock AlertsIndustry, Sector and Symbol Stock ExchangeNASDAQ SectorMedical Industry Pharmaceutical preparations Sub-IndustryPharmaceutical Products Current SymbolNASDAQ:PRTA CIK1559053 Webwww.prothena.com Phone(531) 236-2500Fax353-1902-3510Employees130Year FoundedN/APrice Target and Rating Average Stock Price Target$55.00 High Stock Price Target$110.00 Low Stock Price Target$20.00 Potential Upside/Downside+473.5%Consensus RatingModerate Buy Rating Score (0-4)2.75 Research Coverage8 Analysts Profitability EPS (Most Recent Fiscal Year)($2.30) Trailing P/E RatioN/A Forward P/E RatioN/A P/E GrowthN/ANet Income$-147,030,000.00 Net Margins-90.50% Pretax Margin-105.02% Return on Equity-22.67% Return on Assets-19.68% Debt Debt-to-Equity RatioN/A Current Ratio11.52 Quick Ratio11.52 Sales & Book Value Annual Sales$135.16 million Price / Sales3.82 Cash FlowN/A Price / Cash FlowN/A Book Value$10.46 per share Price / Book0.92Miscellaneous Outstanding Shares53,827,000Free Float38,635,000Market Cap$516.20 million OptionableOptionable Beta0.07 The Best High-Yield Dividend Stocks for 2025Discover the 10 Best High-Yield Dividend Stocks for 2025 and secure reliable income in uncertain markets. 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