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Upturn AI Summary - About
Prothena Corporation plc(PRTA)
Advisory History & Simulated Performance *
*as per simulation (see disclosures)- ALL
- 1Y
- 1M
- 1W
- BUY Advisory
- SELL Advisory (Profit)
- SELL Advisory (Loss)
- Profit
- Loss
- PASS (Skip)
Stock price based on last close Advisory Performance History (Simulated)
Upturn Advisory & Investor View for PRTA
10/19/2026: PRTA (1-star) is currently NOT-A-BUY. Pass it for now.
Prothena Corporation plc is a clinical-stage biotechnology company focused on developing therapies for neurodegenerative and peripheral amyloid diseases. The company is primarily known for its strategic partnership model, where it collaborates with major pharmaceutical firms to co-develop its proprietary antibody-based pipeline. Its main investment appeal lies in the potential for its clinical candidates, such as Prasinezumab and Birtamimab, to address significant unmet medical needs. However, the stock is subject to high risk due to binary trial outcomes, heavy reliance on partners, and a lack of revenue-generating products. It is generally suitable for growth-oriented investors with a high risk tolerance who are closely monitoring clinical milestones.
How to Read the Upturn Advisory
The Upturn Star Rating and the current BUY, SELL, or PASS advisory are generated by Upturn’s AI advisory engine based on proprietary signal analysis, price behavior, advisory history, and historical signal performance.
Company fundamentals, valuation, risks, and news provide supporting context about the business.
Investor Fit
| Investor style | Fit | Why |
|---|---|---|
| Growth investor | Mixed fit | The company offers high-risk, high-reward exposure to breakthrough drug development. |
| Momentum investor | Strong fit while signal remains positive | The stock often reacts sharply to clinical trial catalysts and partnership news. |
| Value investor | Weak fit | The company lacks current earnings and traditional valuation metrics, making it unsuitable for classic value strategies. |
| Dividend investor | Weak fit | Prothena does not pay a dividend. |
| Low-risk investor | Weak fit | High volatility associated with clinical-stage biotech makes this inappropriate for low-risk portfolios. |
Risk Profile
| Risk factor | Level | Why it matters |
|---|---|---|
| Price volatility | High | Clinical results create significant swings in share price. |
| Valuation risk | Medium / high | Valuation is based on future probabilities of drug success rather than current cash flow. |
| Competition risk (Biotech) | High | Competitors like Biogen have deeper resources to bring competing drugs to market. |
| Business quality | Medium | The company is a research entity without its own commercial scale. |
| Dividend income | Low / none | No income is returned to shareholders. |
| Execution risk | High | Failure at any clinical stage can result in significant loss of shareholder value. |
Price Behavior
Downtrend
The stock has experienced a sustained decline in price over recent periods.
Moderately Choppy
The stock has experienced noticeable price swings while retaining some directional structure.
Analysis of Past Performance
Type Stock | Historic Profit -26.51% | Avg. Invested days 26 | Today’s Advisory PASS |
Upturn Advisory Rating  | Upturn Advisory Performance  1.0 | Stock Returns Performance  1.0 |
| Profits based on simulation | Last Close 10/19/2026 |
Upturn Scorecard
Upturn Star Rating 
Company Fundamentals
Financial Health Rating
Growth Momentum Score
Ownership
Top 5 Institutional Investors
Unit Economics (Per $1K Revenue)
Economic Dimensions
Quantitative Style Profile
Style Classification
Quality Focused
Key Highlights
Company Size Small-Cap Stock | Market Capitalization 428.66M USD | Price to earnings Ratio - | 1Y Target Price 21.4 |
Price to earnings Ratio - | 1Y Target Price 21.4 | ||
Volume (30-day avg) 537.2K shares | Beta -0.29 | 52 Weeks Range 7.73 - 11.80 | Updated Date 10/18/2026 |
52 Weeks Range 7.73 - 11.80 | Updated Date 10/18/2026 | ||
Dividends yield (FY) - | Basic EPS (TTM) -0.82 |
How Company Makes Money
| Business area | What it includes | Retail investor read |
|---|---|---|
| Research Collaborations | Milestone payments and royalties from pharmaceutical partners for co-developed therapies. | Revenue is not from direct product sales but from payments earned when drugs reach development goals. |
Analyzing Revenue: Products, Geography and Growth
Revenue by Products
Product revenue - Year on Year
Valuation
Trailing PE - | Forward PE 10.63 | Enterprise Value 164.40M | Price to Sales(TTM) 7.86 |
Enterprise Value 164.40M | Price to Sales(TTM) 7.86 | ||
Enterprise Value to Revenue 3.01 | Enterprise Value to EBITDA -3.58 | Shares Outstanding 51.34M | Shares Floating 34.12M |
Shares Outstanding 51.34M | Shares Floating 34.12M | ||
Percent Insiders 22.56 | Percent Institutions 93.21 |
Financial Metrics
🧭 Investment Snapshot
Total Revenue (Scale)
Total money earned from selling products or services before any costs. It is needed to understand the scale of the business and its ability to generate income.
Net Income (Profit)
Final profit after all expenses, interest, and taxes are deducted. It is needed to determine the overall profitability available to shareholders.
Free Cash Flow (Cash Strength)
Cash remaining after operating activities and capital expenditures, showing cash available for growth. It is needed to evaluate the company’s ability to invest, pay dividends, or reduce debt.
📈 Growth & Strength
Operating Income (Core Profit)
Profit from core operations after deducting all operating expenses. It is needed to measure how efficiently the company runs its primary business activities.
EBITDA (Cash Earnings)
Earnings before interest, taxes, depreciation, and amortization, indicating operating cash potential. It is needed to compare operating performance across companies without accounting or financing differences.
Gross Profit (Unit Profitability)
Revenue minus cost of revenue, showing profit after direct production costs. It is needed to evaluate core business profitability before overhead expenses.
🛡️ Financial Safety
Cash (Liquidity Buffer)
Total cash and cash equivalents on hand. It is needed to evaluate immediate liquidity and financial flexibility.
Total Debt (Leverage Risk)
Total debt including both short-term and long-term components. It is needed to assess the company’s leverage and financial risk.
Net Working Capital (Short-Term Health)
Current assets minus current liabilities, indicating short-term liquidity strength. It is needed to assess whether the company can meet its short-term obligations.
🧱 Balance Sheet Strength
Stockholder Equity (Net Worth)
Total equity value held by shareholders. It is needed to understand the net worth of the company from the owners’ perspective.
Total Assets (Asset Base)
The full value of everything the company owns, including cash, inventory, equipment, and investments. It is needed to understand the resource base used to generate revenue.
Income Before Tax (Pre-Tax Earnings)
Income before provision for income taxes. It is needed to analyze profitability independent of tax structures.
⚙️ Cost & Drag Factors
Cost of Revenue (Production Cost)
Direct costs required to produce and deliver the products or services sold. It is needed to assess efficiency in production and service delivery.
Total Operating Expenses (Operating Cost)
Indirect costs of running the business such as salaries, marketing, and administration. It is needed to understand how much it costs to sustain ongoing business operations.
Income Tax Expense (Tax Drag)
Amount of taxes paid or payable to the government. It is needed to evaluate the impact of taxation on overall profitability.
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