← Back to All US Stocks

Prothena Corp. Public Ltd. Co (PRTA) Stock Fundamental Analysis & AI Rating 2026

PRTA Nasdaq Pharmaceutical Preparations L2 CIK: 0001559053
Recently Updated • Analysis: Apr 14, 2026 • SEC Data: 2025-12-31
STRONG SELL
88% Conf
Pending
Analysis scheduled

📊 PRTA Key Takeaways

Revenue: $9.7M
Net Margin: -2,520.6%
Free Cash Flow: $-163.7M
Current Ratio: 7.72x
Debt/Equity: 0.00x
EPS: $-4.53
AI Rating: STRONG SELL with 88% confidence
Prothena Corp. Public Ltd. Co (PRTA) receives a STRONG SELL rating with 88% confidence from our AI fundamental analysis based on SEC 10-K filings. With revenue of $9.7M, net profit margin of -2,520.6%, and return on equity (ROE) of -87.0%, Prothena Corp. Public Ltd. Co demonstrates mixed fundamentals in the Healthcare sector. Below is our complete PRTA stock analysis for 2026.

Is Prothena Corp. Public Ltd. Co (PRTA) a Good Investment?

Claude

Prothena exhibits severe operational distress with minimal revenue of $9.7M declining 31.5% YoY against massive operating losses of -$214.6M, resulting in negative cash burn of -$163.6M annually. The company is spending over $22 for every $1 of revenue generated, indicating a fundamentally broken business model. With approximately 1.9 years of cash runway remaining at current burn rates, the deteriorating trajectory presents high extinction risk without successful capital raise or clinical/commercial breakthroughs.

Why Buy Prothena Corp. Public Ltd. Co Stock? PRTA Key Strengths

Claude
  • + Strong balance sheet with $307.5M cash and only $46.3M liabilities, providing near-term financial flexibility
  • + Zero long-term debt eliminates refinancing risk and preserves capital raising capacity
  • + Exceptional liquidity position with 7.72x current ratio ensuring short-term solvency

PRTA Stock Risks: Prothena Corp. Public Ltd. Co Investment Risks

Claude
  • ! Catastrophic unprofitability with -2520.6% net margin and -$163.6M annual operating cash burn
  • ! Collapsing revenue base of $9.7M with 31.5% YoY decline suggests failed commercial product strategy or lack of approved assets
  • ! Approximately 1.9 years of cash runway at current burn rate creates existential risk without profitability inflection or successful capital raise

Key Metrics to Watch

Claude
  • * Monthly operating cash burn rate and runway extension timeline
  • * Revenue stabilization and new product approvals or commercial launch success
  • * Operating loss reduction and achievement of cash flow breakeven milestones

Prothena Corp. Public Ltd. Co (PRTA) Financial Metrics & Key Ratios

Revenue
$9.7M
Net Income
$-244.1M
EPS (Diluted)
$-4.53
Free Cash Flow
$-163.7M
Total Assets
$326.8M
Cash Position
$307.5M

💡 AI Analyst Insight

Strong liquidity with a 7.72x current ratio provides a solid financial cushion.

PRTA Profit Margin, ROE & Profitability Analysis

Gross Margin N/A
Operating Margin -2,216.4%
Net Margin -2,520.6%
ROE -87.0%
ROA -74.7%
FCF Margin -1,690.3%

PRTA vs Healthcare Sector: How Prothena Corp. Public Ltd. Co Compares

How Prothena Corp. Public Ltd. Co compares to Healthcare sector averages

Net Margin
PRTA -2,520.6%
vs
Sector Avg 12.0%
PRTA Sector
ROE
PRTA -87.0%
vs
Sector Avg 15.0%
PRTA Sector
Current Ratio
PRTA 7.7x
vs
Sector Avg 2.0x
PRTA Sector
Debt/Equity
PRTA 0.0x
vs
Sector Avg 0.6x
PRTA Sector

Sector benchmarks are approximate industry averages. Actual sector performance may vary.

Is Prothena Corp. Public Ltd. Co Stock Overvalued? PRTA Valuation Analysis 2026

Based on fundamental analysis, Prothena Corp. Public Ltd. Co has mixed fundamental signals relative to the Healthcare sector in 2026.

Return on Equity
-87.0%
Sector avg: 15%
Net Profit Margin
-2,520.6%
Sector avg: 12%
Revenue Growth
N/A
Year-over-year
Debt/Equity
0.00x
Sector avg: 0.6x

Note: This is a fundamental analysis based on SEC filings. For P/E ratio, price targets, and market-based valuation, consult financial data providers. This is not investment advice.

Prothena Corp. Public Ltd. Co Balance Sheet: PRTA Debt, Cash & Liquidity

Current Ratio
7.72x
Quick Ratio
7.72x
Debt/Equity
0.00x
Debt/Assets
14.2%
Interest Coverage
N/A
Long-term Debt
N/A

PRTA Revenue & Earnings Growth: 5-Year Financial Trend

PRTA 5-year financial data: Year 2021: Revenue $200.6M, Net Income -$77.7M, EPS $-1.95. Year 2022: Revenue $200.6M, Net Income -$111.1M, EPS $-2.78. Year 2023: Revenue $200.6M, Net Income $67.0M, EPS $1.38. Year 2024: Revenue $135.2M, Net Income -$116.9M, EPS $-2.47. Year 2025: Revenue $135.2M, Net Income -$147.0M, EPS $-2.76.
Revenue
Net Income
EPS (right axis)

5-Year Trend Summary: Prothena Corp. Public Ltd. Co's revenue has declined by 33% over the 5-year period, indicating business contraction. The most recent EPS of $-2.76 indicates the company is currently unprofitable.

PRTA Revenue Growth, EPS Growth & YoY Performance

Revenue Growth
N/A
Year-over-year
Net Income Growth
N/A
Year-over-year
EPS Growth
N/A
Earnings per share
FCF Margin
-1,690.3%
Free cash flow / Revenue

PRTA Quarterly Earnings & Performance

Quarterly financial performance data for Prothena Corp. Public Ltd. Co including revenue, net income, and earnings per share.
Quarter Revenue Net Income EPS
Q3 2025 $970.0K -$36.5M $-0.68
Q2 2025 $4.4M -$5.4M $-0.10
Q1 2025 $50.0K -$60.2M $-1.12
Q3 2024 $970.0K $21.9M $0.38
Q2 2024 $4.0M -$5.4M $-0.10
Q1 2024 $50.0K -$46.9M $-0.89
Q3 2023 $1.5M $21.9M $0.38
Q2 2023 $1.3M -$36.3M $-0.88

Data sourced from SEC EDGAR 10-Q quarterly filings. Figures may represent quarterly or cumulative values.

Prothena Corp. Public Ltd. Co Dividends, Buybacks & Capital Allocation

Operating Cash Flow
-$163.6M
Cash generated from operations
Capital Expenditures
$110.0K
Investment in assets
Dividends
None
No dividend program

PRTA SEC Filings: Latest 10-K & 10-Q Analysis

Access official SEC EDGAR filings for Prothena Corp. Public Ltd. Co (CIK: 0001559053)

📋 Recent SEC Filings

Date Form Document Action
Apr 10, 2026 4 xslF345X06/form4.xml View →
Mar 27, 2026 DEF 14A prta-20260327.htm View →
Mar 5, 2026 4 xslF345X05/form4.xml View →
Mar 5, 2026 4 xslF345X05/form4.xml View →
Mar 5, 2026 4 xslF345X05/form4.xml View →

Frequently Asked Questions about PRTA

What is the AI rating for PRTA?

Prothena Corp. Public Ltd. Co (PRTA) has an AI rating of STRONG SELL with 88% confidence, based on fundamental analysis of SEC EDGAR filings.

What are PRTA's key strengths?

Claude: Strong balance sheet with $307.5M cash and only $46.3M liabilities, providing near-term financial flexibility. Zero long-term debt eliminates refinancing risk and preserves capital raising capacity.

What are the risks of investing in PRTA?

Claude: Catastrophic unprofitability with -2520.6% net margin and -$163.6M annual operating cash burn. Collapsing revenue base of $9.7M with 31.5% YoY decline suggests failed commercial product strategy or lack of approved assets.

What is PRTA's revenue and growth?

Prothena Corp. Public Ltd. Co reported revenue of $9.7M.

Does PRTA pay dividends?

Prothena Corp. Public Ltd. Co does not currently pay dividends.

Where can I find PRTA SEC filings?

Official SEC filings for Prothena Corp. Public Ltd. Co (CIK: 0001559053) including 10-K, 10-Q, and 8-K reports are available on SEC EDGAR.

What is PRTA's EPS?

Prothena Corp. Public Ltd. Co has a diluted EPS of $-4.53.

How is the AI analysis conducted?

Two independent AI systems — Claude (Anthropic) and ChatGPT (OpenAI) — analyze SEC EDGAR filings including 10-K annual reports and 10-Q quarterly reports. Each AI evaluates financial health, profitability ratios, balance sheet strength, and growth metrics. The combined rating reflects both perspectives for balanced insights.

Is PRTA a good stock to buy right now?

Based on our AI fundamental analysis in April 2026, Prothena Corp. Public Ltd. Co has a STRONG SELL rating with 88% confidence. Review the strengths and risks sections above before making a decision. This is not investment advice.

Is PRTA stock overvalued or undervalued?

Valuation metrics for PRTA: ROE of -87.0% (sector avg: 15%), net margin of -2,520.6% (sector avg: 12%). Compare these metrics with sector averages to assess valuation.

Should I buy PRTA stock in 2026?

Our dual AI analysis gives Prothena Corp. Public Ltd. Co a combined STRONG SELL rating for 2026. Revenue is data pending, with profitability at or below sector average. Always conduct your own research.

What is PRTA's free cash flow?

Prothena Corp. Public Ltd. Co's operating cash flow is $-163.6M, with capital expenditures of $110.0K. FCF margin is -1,690.3%.

How does PRTA compare to other Healthcare stocks?

Vs Healthcare sector averages: Net margin -2,520.6% (avg: 12%), ROE -87.0% (avg: 15%), current ratio 7.72 (avg: 2).

Top Rated Stocks
NSSC 92% MLI 92% MELI 92% MDXG 92% MANH 92% INVA 92% GGG 92% GCT 92% FTNT 92% FSLR 92%
Sector: All Healthcare Stocks →
Disclaimer: This analysis is generated by Claude AI (Anthropic) and ChatGPT (OpenAI) based on publicly available SEC EDGAR filings. It does not include stock price data and should not be considered financial advice. All fundamental data is sourced from SEC public domain filings. Always conduct your own research and consult with a qualified financial advisor before making investment decisions.
Data Source: SEC EDGAR | Analysis Date: Apr 14, 2026 | Data as of: 2025-12-31 | Powered by Claude AI