Prothena/$PRTA
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Capital at risk
About Prothena
Prothena Corp PLC is a late-stage clinical biotechnology company that focuses on protein dysregulation and a pipeline of investigational therapeutics with the potential to change the course of devastating neurodegenerative and rare and peripheral amyloid diseases. Prothena is developing and applying its proprietary CYTOPE technology to target a broad spectrum of intracellular disease pathways in the brain and periphery. The company's pipeline includes both wholly-owned and partnered programs like Prasinezumab, Coramitug (PRX004), BMS-986446 (PRX005), PRX019, TDP-43 CYTOPE, and PRX012-TfR, being developed for the potential treatment of Parkinson's disease, ATTR amyloidosis with cardiomyopathy, Alzheimer's disease, Amyotrophic lateral sclerosis (ALS), and other neurodegenerative diseases.
- Ticker
- $PRTA
- Sector
- Health
- Primary listing
- NASDAQ
- Employees
- 67
- Headquarters
- Dublin, Ireland
- Website
- www.prothena.com
Prothena Metrics
BasicAdvanced
$435M
-
-$0.83
-0.35
-
Price and volume
Market cap
$435M
Beta
-0.35
52-week high
$11.80
52-week low
$7.73
Average daily volume
536K
Financial strength
Current ratio
25.048
Quick ratio
24.721
Long term debt to equity
0.014
Total debt to equity
0.024
Profitability
EBITDA (TTM)
-59.04
Gross margin (TTM)
-19.11%
Net profit margin (TTM)
-80.67%
Operating margin (TTM)
-109.79%
Effective tax rate (TTM)
0.81%
Revenue per employee (TTM)
$810,000
Management effectiveness
Return on assets (TTM)
-10.67%
Return on equity (TTM)
-14.39%
Valuation
Price to revenue (TTM)
8.291
Price to book
1.53
Price to tangible book (TTM)
1.53
Price to free cash flow (TTM)
-7.447
Free cash flow yield (TTM)
-13.43%
Free cash flow per share (TTM)
-1.137
Growth
Revenue change (TTM)
427.32%
Earnings per share change (TTM)
-85.19%
3-year revenue growth (CAGR)
-1.83%
10-year revenue growth (CAGR)
44.93%
3-year earnings per share growth (CAGR)
-33.19%
10-year earnings per share growth (CAGR)
-13.37%
What the Analysts think about Prothena
Analyst ratings (Buy, Hold, Sell) for Prothena stock.
Analyst projections of the future price of Prothena stock.
Bulls say / Bears say
Roche’s Phase 2b PADOVA results showed exploratory clinical and biological signals that were consistent across clinical and biomarker measures. The findings support taking prasinezumab into Phase 3, although they do not yet prove it works. (BioSpace)
Coramitug has FDA Fast Track status and is being tested in a large Phase 3 study for ATTR cardiomyopathy. Earlier Phase 2 results showed improvement in a heart-failure biomarker and several measures of heart function, giving the programme clinical support beyond its disease rationale. (BioSpace)
Prothena ended Q2 with $289.1 million in cash and expects only $18–23 million of net cash use from operations and investing for 2026. This gives it a substantial buffer while partners advance its clinical programmes. (Last10K)
The PADOVA findings were described as exploratory, so they are not conclusive evidence that prasinezumab changes Parkinson’s disease progression. The ongoing Phase 3 trial still has to establish whether the signal translates into a clear clinical benefit. (BioSpace)
Prothena’s Phase 1 results for its wholly owned Alzheimer’s antibody PRX012 showed higher rates of ARIA-E, a brain-swelling safety issue, than approved anti-amyloid antibodies. That could limit how suitable the drug is for patients, despite its ability to reduce amyloid plaque. (MarketScreener)
Prothena has little current revenue to cushion delays: Q2 revenue was $1.01 million and it still reported an $18.6 million loss. Its two largest partnered Phase 3 programmes are not expected to reach primary completion until 2029, leaving years before pivotal results could validate them. (Simply Wall St, City A.M.)
Data summarised monthly by Lightyear AI. Last updated on 9 Oct 2026.
Prothena Financial Performance
Revenues and expenses
Prothena Earnings Performance
Company profitability
Upcoming events
No upcoming events
Prothena News
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Funds containing Prothena
Fund name | Fund size | $PRTA weighting |
|---|---|---|
iShares Healthcare Innovation£DRDR | $1.3B | 0.04% |
iShares Healthcare Innovation€2B78 | $1.2B | 0.04% |
iShares Healthcare Innovation$HEAL | $1.3B | 0.04% |
iShares Ageing Population$AGED | $953M | 0.03% |
iShares Nasdaq US Biotechnology£BTEK | $1.1B | 0.03% |
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