(PRTA) Prothena - Overview
Stock: Antibody, Vaccine, Neurodegenerative, Amyloidosis, Synucleinopathy
EPS (Earnings per Share)
Revenue
| Risk 5d forecast | |
|---|---|
| Volatility | 64.0% |
| Relative Tail Risk | -10.2% |
| Reward TTM | |
|---|---|
| Sharpe Ratio | -0.69 |
| Alpha | -51.60 |
| Character TTM | |
|---|---|
| Beta | 0.521 |
| Beta Downside | 0.913 |
| Drawdowns 3y | |
|---|---|
| Max DD | 94.17% |
| CAGR/Max DD | -0.50 |
Description: PRTA Prothena December 29, 2025
Prothena Corporation plc (NASDAQ: PRTA) is a Dublin-based, late-stage clinical biotech focused on protein-dysregulation diseases, primarily neurodegenerative disorders. Its lead asset, prasinezumab-a humanized monoclonal antibody targeting α-synuclein-is in a Phase 2b trial for Parkinson’s disease and related synucleinopathies, representing the company’s most advanced commercial candidate.
The pipeline also includes: Coramytug (Phase 2 for transthyretin amyloidosis), BMS-986446 (Phase 2 for Alzheimer’s disease), PRX012 (Phase 1 Alzheimer’s), PRX123 (preclinical dual Aβ-Tau vaccine), and PRX019 (Phase 1 for broader neurodegeneration). Strategic collaborations with Roche (α-synuclein) and Bristol Myers Squibb (tau, TDP-43) provide milestone payments and shared development costs.
Key metrics (as of Q3 2024): market cap ≈ $250 M, cash runway of ~ 18 months, R&D expense ~ $45 M YoY, and a 12-month forward-looking earnings-before-interest-taxes-depreciation-amortisation (EBITDA) breakeven probability of ~ 30 % based on historical biotech success rates. Sector drivers include an aging U.S. population (≈ 20 % over 65) and rising prevalence of Parkinson’s and Alzheimer’s, which have collectively attracted > $12 B of U.S. biotech venture capital in 2023.
For a deeper quantitative assessment, see the ValueRay platform’s detailed PRTA valuation model.
Piotroski VR‑10 (Strict, 0-10) 0.0
| Net Income: -280.5m TTM > 0 and > 6% of Revenue |
| FCF/TA: -0.53 > 0.02 and ΔFCF/TA -27.32 > 1.0 |
| NWC/Revenue: 2448 % < 20% (prev 366.4%; Δ 2082 % < -1%) |
| CFO/TA -0.53 > 3% & CFO -188.0m > Net Income -280.5m |
| Net Debt/EBITDA: error (EBITDA <= 0) |
| Current Ratio: 6.61 > 1.5 & < 3 |
| Outstanding Shares: last quarter (53.8m) vs 12m ago 0.07% < -2% |
| Gross Margin: -153.3% > 18% (prev 0.10%; Δ -15.3k% > 0.5%) |
| Asset Turnover: 2.49% > 50% (prev 22.40%; Δ -19.92% > 0%) |
| Interest Coverage Ratio: -11.30 > 6 (EBITDA TTM -217.8m / Interest Expense TTM 19.4m) |
Altman Z'' -15.00
| A: 0.82 (Total Current Assets 340.0m - Total Current Liabilities 51.4m) / Total Assets 352.6m |
| B: -3.76 (Retained Earnings -1.32b / Total Assets 352.6m) |
| C: -0.46 (EBIT TTM -218.7m / Avg Total Assets 473.9m) |
| D: -22.98 (Book Value of Equity -1.32b / Total Liabilities 57.6m) |
| Altman-Z'' Score: -34.11 = D |
What is the price of PRTA shares?
Over the past week, the price has changed by -7.84%, over one month by -8.24%, over three months by -18.70% and over the past year by -43.50%.
Is PRTA a buy, sell or hold?
- StrongBuy: 5
- Buy: 3
- Hold: 2
- Sell: 0
- StrongSell: 0
What are the forecasts/targets for the PRTA price?
| Issuer | Target | Up/Down from current |
|---|---|---|
| Wallstreet Target Price | 20.3 | 143.5% |
| Analysts Target Price | 20.3 | 143.5% |
| ValueRay Target Price | 6.1 | -26.7% |
PRTA Fundamental Data Overview February 03, 2026
P/S = 40.2378
P/B = 1.6067
P/EG = 0.8
Revenue TTM = 11.8m USD
EBIT TTM = -218.7m USD
EBITDA TTM = -217.8m USD
Long Term Debt = 9.08m USD (from capitalLeaseObligations, last quarter)
Short Term Debt = 2.88m USD (from shortTermDebt, last quarter)
Debt = 9.08m USD (from shortLongTermDebtTotal, last quarter)
Net Debt = -321.8m USD (from netDebt column, last quarter)
Enterprise Value = 152.5m USD (474.2m + Debt 9.08m - CCE 330.8m)
Interest Coverage Ratio = -11.30 (Ebit TTM -218.7m / Interest Expense TTM 19.4m)
EV/FCF = -0.81x (Enterprise Value 152.5m / FCF TTM -188.2m)
FCF Yield = -123.4% (FCF TTM -188.2m / Enterprise Value 152.5m)
FCF Margin = -1597 % (FCF TTM -188.2m / Revenue TTM 11.8m)
Net Margin = -2380 % (Net Income TTM -280.5m / Revenue TTM 11.8m)
Gross Margin = -153.3% ((Revenue TTM 11.8m - Cost of Revenue TTM 29.9m) / Revenue TTM)
Gross Margin QoQ = none% (prev 100.0%)
Tobins Q-Ratio = 0.43 (Enterprise Value 152.5m / Total Assets 352.6m)
Interest Expense / Debt = 72.11% (Interest Expense 6.55m / Debt 9.08m)
Taxrate = 21.0% (US default 21%)
NOPAT = -172.7m (EBIT -218.7m * (1 - 21.00%)) [loss with tax shield]
Current Ratio = 6.61 (Total Current Assets 340.0m / Total Current Liabilities 51.4m)
Debt / Equity = 0.03 (Debt 9.08m / totalStockholderEquity, last quarter 295.0m)
Debt / EBITDA = 1.48 (negative EBITDA) (Net Debt -321.8m / EBITDA -217.8m)
Debt / FCF = 1.71 (negative FCF - burning cash) (Net Debt -321.8m / FCF TTM -188.2m)
Total Stockholder Equity = 386.0m (last 4 quarters mean from totalStockholderEquity)
RoA = -59.18% (Net Income -280.5m / Total Assets 352.6m)
RoE = -72.66% (Net Income TTM -280.5m / Total Stockholder Equity 386.0m)
RoCE = -55.35% (EBIT -218.7m / Capital Employed (Equity 386.0m + L.T.Debt 9.08m))
RoIC = -44.75% (negative operating profit) (NOPAT -172.7m / Invested Capital 386.0m)
WACC = 7.69% (E(474.2m)/V(483.3m) * Re(7.84%) + (debt cost/tax rate unavailable))
Discount Rate = 7.84% (= CAPM, Blume Beta Adj.) -> floored to rf + 0.7*ERP = 7.95%
Shares Correlation 3-Years: 100.0 | Cagr: 0.15%
Fair Price DCF = unknown (Cash Flow -188.2m)
EPS Correlation: -1.23 | EPS CAGR: 15.97% | SUE: 0.72 | # QB: 0
Revenue Correlation: 4.90 | Revenue CAGR: 21.26% | SUE: -0.10 | # QB: 0
EPS next Quarter (2026-03-31): EPS=-0.32 | Chg30d=-0.060 | Revisions Net=+2 | Analysts=2
EPS next Year (2026-12-31): EPS=0.53 | Chg30d=+1.249 | Revisions Net=+1 | Growth EPS=+111.6% | Growth Revenue=+1072.2%