| Index | — | P/E | — | EPS (ttm) | -0.84 | Insider Own | 24.34% | Shs Outstand | 51.34M | Perf Week | 3.29% |
| Market Cap | 434.82M | Forward P/E | — | EPS next Y | -1.02 | Insider Trans | 11.08% | Shs Float | 43.91M | Perf Month | -0.82% |
| Enterprise Value | 153.82M | PEG | — | EPS next Q | -0.21 | Short Float | 18.08% | Perf Quarter | 1.68% | ||
| Income | -45.00M | P/S | 8.05 | EPS this Y | — | Short Ratio | 16.34 | Perf Half Y | -20.39% | ||
| Sales | 54.00M | P/B | 1.52 | EPS next Y | -962.66% | ROA | -14.54% | Short Interest | 7.94M | Perf YTD | -11.31% |
| Book/sh | 5.59 | P/C | 1.51 | EPS next 5Y | 92.79% | ROE | -14.98% | 52W High | 11.80 -28.22% | Perf Year | -20.47% |
| Cash/sh | 5.61 | P/FCF | — | EPS past 3/5Y | — | ROIC | -21.36% | 52W Low | 7.73 9.57% | Perf 3Y | -78.65% |
| Dividend Est. | — | EV/EBITDA | — | Sales past 3/5Y | -43.00% 58.49% | Gross Margin | 43.52% | Volatility | 5.62% 5.08% | Perf 5Y | -86.25% |
| Dividend TTM | — | EV/Sales | 2.85 | EPS Y/Y TTM | — | Oper. Margin | -115.09% | ATR (14) | 0.43 | Perf 10Y | -84.66% |
| Dividend Ex-Date | — | Quick Ratio | 25.05 | Sales Y/Y TTM | 440.00% | Profit Margin | -80.67% | RSI (14) | 48.40 | Recom | 2.36 |
| Dividend Gr. 3/5Y | — | Current Ratio | 25.05 | EPS Q/Q | 82.80% | SMA20 | 0.03% | Beta | -0.22 | Target Price | 30.00 |
| Payout | 0.00% | Debt/Eq | 0.02 | Sales Q/Q | -75.00% | SMA50 | -3.35% | Rel Volume | 0.96 | Prev Close | 8.88 |
| Employees | 67 | LT Debt/Eq | 0.01 | Earnings | Feb 25 | SMA200 | -8.30% | Avg Volume | 469.87K | Price | 8.47 |
| IPO Date | Dec 20, 2012 | Option/Short | Yes / Yes | EPS/Sales Surpr. | 17.95% 139.53% | Net Debt/EBITDA | — | Volume | 452,298 | Change | -4.62% |
| Date | Action | Analyst | Rating | Target |
|---|---|---|---|---|
| Jul-24-26 | Reiterated | H.C. Wainwright | Buy | $20 → $30 |
| Mar-13-26 | Reiterated | Stifel Nicolaus | $19 | |
| Dec-01-25 | Reiterated | JMP Securities | Market Outperform | $11 → $19 |
| Dec-01-25 | Reiterated | Deutsche Bank | Buy | $19 |
| Oct-28-25 | Reiterated | UBS | Buy | $15 |
| Oct-28-25 | Reiterated | Piper Sandler | Overweight | |
| Oct-07-25 | Reiterated | HC Wainwright & Co. | Buy | $20 |
| Sep-02-25 | Reiterated | JMP Securities | Market Outperform | $11 |
| May-28-25 | Downgrade | B of A Securities | Neutral → Underperform | |
| May-27-25 | Downgrade | Oppenheimer | Outperform → Perform |
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.
Per-holder 13F data hasn't been ingested for this ticker yet.
| Line Item (USD, M) | TTM — | FY 2025 12/31/2025 | FY 2024 12/31/2024 | FY 2023 12/31/2023 | FY 2022 12/31/2022 | FY 2021 12/31/2021 | FY 2020 12/31/2020 | FY 2019 12/31/2019 | FY 2018 12/31/2018 | |
|---|---|---|---|---|---|---|---|---|---|---|
| Total Revenue | 54 | 10 | 135 | 91 | — | — | — | — | — | |
| Cost of Goods Sold Incl. D&A | 31 | 4 | 0 | 0 | — | — | — | — | — | |
| Gross Profit | 23 | 6 | 135 | 91 | — | — | — | — | — | |
| Selling, General and Administrative Excl. Other | 50 | 59 | 67 | 62 | — | — | — | — | — | |
| Research and Development | 66 | 135 | 223 | 221 | — | — | — | — | — | |
| Other Operating Expense | -30 | -3 | 0 | -1 | — | — | — | — | — | |
| Operating Income | -62 | -185 | -155 | -191 | — | — | — | — | — | |
| Interest Expense | 0 | 0 | 0 | 0 | — | — | — | — | — | |
| Unusual Expense | — | — | — | — | — | — | — | — | — | |
| Non-Operating Income (Expense) | 20 | -16 | 26 | 31 | — | — | — | — | — | |
| Net Income Before Taxes | -44 | -201 | -129 | -160 | — | — | — | — | — | |
| Income Taxes | 0 | 43 | -7 | -13 | — | — | — | — | — | |
| Consolidated Net Income | -45 | -244 | -122 | -147 | — | — | — | — | — | |
| Net Income From Continuing Operations | -45 | -244 | -122 | -147 | — | — | — | — | — | |
| Net Income | -45 | -244 | -122 | -147 | — | — | — | — | — | |
| EPS (Recurring) | -0.83 | -4.53 | -2.27 | -2.76 | — | — | — | — | — | |
| EPS (Basic, Before Extraordinaries) | -0.83 | -4.53 | -2.27 | -2.76 | — | — | — | — | — | |
| EPS (Diluted) | -0.84 | -4.53 | -2.27 | -2.76 | — | — | — | — | — | |
| EBITDA | -42 | -200 | -128 | -160 | — | — | — | — | — | |
| Other After Tax Adjustments | — | — | — | — | — | — | — | — | — | |
| Stock Option Compensation Expense | — | — | — | — | — | — | — | — | — | |
| Price To Earnings Ratio | — | — | — | — | — | — | — | — | — | |
| Price To Sales Ratio | 8.16 | 51.57 | 5.54 | 21.17 | — | — | — | — | — | |
| Gross Margin | 42.59 | 60.00 | 100.00 | 100.00 | — | — | — | — | — | |
| Operating Margin | -114.81 | -1,850.00 | -114.81 | -209.89 | — | — | — | — | — | |
| Net Margin | -83.33 | -2,440.00 | -90.37 | -161.54 | — | — | — | — | — | |
| Shares Outstanding | 52 | 54 | 54 | 53 | — | — | — | — | — | |
| Market Capitalization | 440 | 516 | 748 | 1,926 | — | — | — | — | — | |
| Operating Lease Expense | — | — | — | — | — | — | — | — | — |
| Insider | Relationship | Date | Transaction | Cost | #Shares | Value ($) | #Shares Total | SEC Form 4 |
|---|---|---|---|---|---|---|---|---|
| SCULLY WILLIAM P | 10% Owner | Oct 23 '26 | Buy | 8.07 | 50,000 | 403,525 | 1,187,000 | Oct 26 |
| SCULLY WILLIAM P | 10% Owner | Oct 22 '26 | Buy | 8.19 | 100,000 | 818,520 | 1,137,000 | Oct 26 |
| SCULLY WILLIAM P | 10% Owner | Oct 14 '26 | Buy | 8.46 | 10,000 | 84,569 | 1,037,000 | Oct 15 |
| SCULLY WILLIAM P | 10% Owner | Oct 13 '26 | Buy | 8.35 | 100,000 | 835,480 | 1,027,000 | Oct 15 |
| SCULLY WILLIAM P | 10% Owner | Oct 08 '26 | Buy | 8.57 | 90,000 | 770,904 | 529,000 | Oct 09 |
| SCULLY WILLIAM P | 10% Owner | Oct 07 '26 | Buy | 8.40 | 125,000 | 1,050,150 | 439,000 | Oct 09 |
| SCULLY WILLIAM P | 10% Owner | Oct 02 '26 | Buy | 8.57 | 100,000 | 857,240 | 314,000 | Oct 06 |
| SCULLY WILLIAM P | 10% Owner | Sep 29 '26 | Buy | 8.68 | 162,000 | 1,405,674 | 214,000 | Sep 30 |
| SCULLY WILLIAM P | 10% Owner | Sep 28 '26 | Buy | 8.60 | 103,500 | 889,872 | 187,000 | Sep 29 |
| SCULLY WILLIAM P | 10% Owner | Sep 18 '26 | Buy | 8.43 | 100,000 | 843,460 | 927,000 | Sep 21 |
| SCULLY WILLIAM P | 10% Owner | Sep 02 '26 | Buy | 9.47 | 27,000 | 255,739 | 827,000 | Sep 03 |
| SCULLY WILLIAM P | 10% Owner | Aug 20 '26 | Buy | 8.79 | 50,000 | 439,430 | 800,000 | Aug 21 |
| SCULLY WILLIAM P | 10% Owner | Aug 07 '26 | Buy | 8.62 | 37,500 | 323,220 | 790,000 | Aug 10 |
| Isaacs Michael John | General Counsel & Company Sec. | Jul 29 '26 | Sale | 8.47 | 8,386 | 71,055 | 35,745 | Jul 30 |
| Kingston Anne Evans | Chief Strategy Officer | Jul 29 '26 | Sale | 8.47 | 7,662 | 64,919 | 55,782 | Jul 30 |