Prothena (PRTA) Stock Chart & Stock Price History $9.65 -0.05 (-0.52%) Closing price 04:00 PM EasternExtended Trading$9.64 -0.02 (-0.16%) As of 06:30 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 Chart Stock AnalysisAnalyst ForecastsChartCompetitorsEarningsFinancialsHeadlinesInsider TradesOptions ChainOwnershipSEC FilingsShort InterestTrendsBuy This Stock Prothena Stock Price Performance 5 Day Performance+0.26%1 Month Performance-26.83%3 Month Performance-39.76%6 Month Performance-45.34%Year-To-Date Performance-30.58%1 Year Performance-53.93% Receive PRTA Stock News and Ratings via EmailSign-up to receive the latest news and ratings for Prothena and its competitors with MarketBeat's FREE daily newsletter. Email Address PRTA Stock Chart for Monday, April, 28, 2025 PRTA Chart by TradingView Prothena Stock Price History Daily Weekly Monthly Time Frame Custom Range 1 Month 3 Months 6 Months Year-to-Date 1 Year Time Frame Start Date End Date Export to Excel DateOpening PriceClosing PriceHighLowVolumeMarket Capitalization04/25/2025$9.65$9.70+0.52%$9.84$9.39490,570 shs$522.12 million04/24/2025$9.59$9.65+0.63%$9.98$9.45385,916 shs$519.43 million04/23/2025$9.54$9.59+0.52%$10.07$9.44836,739 shs$516.20 million04/22/2025$9.30$9.54+2.58%$9.65$9.211.08 million shs$513.51 million04/21/2025$9.20$9.30+1.09%$9.97$9.00774,020 shs$500.59 million04/18/2025$9.20$9.20$9.48$9.10340,979 shs$495.21 million04/17/2025$9.26$9.20-0.65%$9.48$9.10340,979 shs$495.21 million04/16/2025$9.59$9.26-3.44%$9.58$9.15400,107 shs$498.44 million04/15/2025$9.94$9.59-3.52%$10.04$9.40498,656 shs$516.20 million04/14/2025$10.22$9.94-2.74%$10.45$9.75387,199 shs$535.04 million Get the Latest News and Ratings for PRTA and Related StocksEnter your email address below to receive the latest news and analysts' ratings for Prothena and its competitors with MarketBeat's FREE daily newsletter. 04/11/2025$9.69$10.22+5.47%$10.27$9.59443,720 shs$550.11 million04/10/2025$10.26$9.69-5.56%$10.16$9.54460,785 shs$521.58 million04/09/2025$10.48$10.26-2.10%$10.79$9.301.33 million shs$552.27 million04/09/2025$10.48$10.26-2.10%$10.79$9.301.33 million shs$552.27 million04/08/2025$10.84$10.48-3.32%$11.50$10.35746,553 shs$564.11 million04/08/2025$10.84$10.48-3.32%$11.50$10.35746,553 shs$564.11 million04/07/2025$10.86$10.84-0.18%$11.28$10.001.13 million shs$583.49 million04/04/2025$11.32$10.86-4.06%$11.37$10.68416,995 shs$584.56 million04/03/2025$12.14$11.32-6.75%$11.84$11.11456,544 shs$609.32 million04/02/2025$11.74$12.14+3.41%$12.20$11.54557,435 shs$653.46 million04/01/2025$12.38$11.74-5.17%$12.45$11.42955,283 shs$631.93 million03/31/2025$13.14$12.38-5.78%$12.71$11.78535,684 shs$666.38 million03/28/2025$13.01$13.14+1.00%$13.22$12.70211,926 shs$707.29 million03/27/2025$13.37$13.01-2.69%$13.52$12.71284,214 shs$700.29 million Related Companies Schrödinger Stock Chart Denali Therapeutics Stock Chart Mirum Pharmaceuticals Stock Chart Tarsus Pharmaceuticals Stock Chart Gemini Therapeutics Stock Chart Beam Therapeutics Stock Chart NewAmsterdam Pharma Stock Chart Kymera Therapeutics Stock Chart Belite Bio Stock Chart Bausch Health Companies Stock Chart Receive PRTA Stock News and Ratings via EmailSign-up to receive the latest news and ratings for Prothena and its competitors with MarketBeat's FREE daily newsletter. 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