Prothena (PRTA) Stock Overview
A late-stage clinical biotechnology company, focuses on discovery and development of novel therapies to treat diseases caused by protein dysregulation. More details
| Snowflake Score | |
|---|---|
| Valuation | 4/6 |
| Future Growth | 5/6 |
| Past Performance | 0/6 |
| Financial Health | 5/6 |
| Dividends | 0/6 |
Rewards
Risk Analysis
No risks detected for PRTA from our risk checks.
PRTA Community Fair Values
Create NarrativeSee what 9 others think this stock is worth. Follow their fair value or set your own to get alerts.
Analyst Price Targets
Pharmaceuticals & Biotech opportunity
ST
Fair Value from
US$21.5362.9% undervalued intrinsic discount
Looking to be second time lucky with a game-changing new product
Key Takeaways Unicycive has successfully completed clinical development of its lead asset, Oxylanthanum Carbonate (OLC). OLC has been designed to improve on current phosphate binders by offering better efficacy, fewer pills, and improved tolerability over alternative treatments for hyperphosphatemia chronic kidney disease patients on dialysis.
Read full narrativeProthena Corporation plc Competitors
Price History & Performance
| Historical stock prices | |
|---|---|
| Current Share Price | US$10.79 |
| 52 Week High | US$11.69 |
| 52 Week Low | US$4.32 |
| Beta | -0.33 |
| 1 Month Change | 9.43% |
| 3 Month Change | 22.89% |
| 1 Year Change | 33.54% |
| 3 Year Change | -85.97% |
| 5 Year Change | -53.87% |
| Change since IPO | 49.86% |
Recent News & Updates
PRTA: ATTR Milestones And Share Repurchase Plan Will Support Future Upside
Analysts maintained Prothena's fair value estimate at $21.00, citing largely unchanged assumptions regarding revenue growth, profit margin, discount rate, and a very large future P/E multiple. What's in the News Prothena has earned $150 million to date out of up to $1.2 billion in eligible milestone payments from Novo Nordisk under their ATTR amyloidosis agreement.PRTA: ATTR Milestones And Share Repurchase Will Drive Future Upside
Analysts have kept their price target for Prothena broadly unchanged at $21.00, with only slight adjustments to underlying assumptions on discount rate, revenue growth, profit margin and future P/E, in order to better reflect their current view of the stock's risk and earnings profile. What's in the News Prothena has earned $150 million to date of the total eligible milestone payments of up to $1.2 billion from Novo Nordisk under their ATTR amyloidosis agreement, including a recent $50 million milestone tied to a prespecified enrollment target in the ongoing Phase 3 CLEOPATTRA trial of coramitug for ATTR-CM (Key Developments).Recent updates
PRTA: ATTR Milestones And Share Repurchase Plan Will Support Future Upside
Analysts maintained Prothena's fair value estimate at $21.00, citing largely unchanged assumptions regarding revenue growth, profit margin, discount rate, and a very large future P/E multiple. What's in the News Prothena has earned $150 million to date out of up to $1.2 billion in eligible milestone payments from Novo Nordisk under their ATTR amyloidosis agreement.PRTA: ATTR Milestones And Share Repurchase Will Drive Future Upside
Analysts have kept their price target for Prothena broadly unchanged at $21.00, with only slight adjustments to underlying assumptions on discount rate, revenue growth, profit margin and future P/E, in order to better reflect their current view of the stock's risk and earnings profile. What's in the News Prothena has earned $150 million to date of the total eligible milestone payments of up to $1.2 billion from Novo Nordisk under their ATTR amyloidosis agreement, including a recent $50 million milestone tied to a prespecified enrollment target in the ongoing Phase 3 CLEOPATTRA trial of coramitug for ATTR-CM (Key Developments).PRTA: Share Buyback And ATTR Milestones Will Support Future Upside
Analysts have nudged their price target on Prothena to $21.00 from $20.50, reflecting updated assumptions on growth, margins, and a very large prospective future P/E multiple. What's in the News Prothena has earned a total of $150 million to date from potential milestone payments of up to $1.2 billion under its ATTR amyloidosis agreement with Novo Nordisk, tied to clinical development and sales milestones (Key Developments).PRTA: Share Buyback And Index Inclusion Will Support Future Upside
Analysts now set their Prothena price target at about $20.50, compared with roughly $20.33 previously. This reflects updated assumptions around revenue growth, profit margins and future P/E levels.
Bullish View Expects Partnered Neurology Pipeline And CYTOPE Platform To Reshape Long-Term Prospects
Catalysts About Prothena Prothena is a late stage biotech company focused on protein misfolding and neurodegenerative diseases through partnered and wholly owned antibody and CYTOPE programs. What are the underlying business or industry changes driving this perspective?PRTA: Index Inclusion And ALS Platform Milestones Will Drive Future Upside
Analysts maintained their Prothena fair value estimate at $20.33 per share, making only minor adjustments to assumptions such as discount rate, revenue growth, profit margin, and future P/E, which together support this unchanged price target. What's in the News Prothena Corporation plc was added to the S&P Biotechnology Select Industry Index, which can increase visibility for the stock among index-tracking funds and sector-focused investors (Key Developments).PRTA: Future Milestones From ALS Platform And ATTR Program Will Drive Upside
Analysts have trimmed their price target for Prothena to about US$20.33 per share, reflecting slightly adjusted assumptions around discount rate, profit margin, and future P/E that fine tune rather than overhaul their prior view. What's in the News Prothena was added to the S&P Biotechnology Select Industry Index, putting the stock into a tracked industry benchmark that some index funds and ETFs follow (Index Constituent Adds).PRTA: Partnered Royalties And Milestones Will Drive Upside Over Next 12 Months
Narrative update Analysts have lifted their price target on Prothena to US$36 from US$15, highlighting the value they see in the partnered pipeline and its potential for net sales royalties and milestone payments over the catalyst-heavy year ahead. Analyst Commentary Bullish analysts are pointing to the recent price target revision to US$36 as a signal that the market may be underappreciating the potential value of Prothena's partnered programs, especially the royalty and milestone streams that could build over time.PRTA: Partnered Royalties And Milestones Will Drive Upside Over Catalyst-Rich Year
Narrative Update Analysts have raised their price target on Prothena to US$36 from US$15, citing what they describe as strong potential in the company's partnered pipeline, including expected net sales royalties and milestone payments over the coming year and in subsequent periods. Analyst Commentary Recent commentary from bullish analysts centers on the uplift in the price target to US$36, tied directly to how they see Prothena executing on its partnered programs and the potential cash flows that could come from those collaborations.PRTA: Partnered Pipeline Milestones Will Drive Upside Over Catalyst-Rich Year Ahead
Analysts have significantly raised their price target on Prothena to $36 from $15, reflecting increased confidence in the lucrative potential of its partnered pipeline, including expected net sales royalties, milestone payments, and a catalyst-rich outlook over the next year. Analyst Commentary Bullish analysts highlight that the substantial price target increase is grounded in greater conviction around Prothena's partnered pipeline, which they see as a key driver of long term value creation and multiple expansion.We Think Prothena (NASDAQ:PRTA) Can Afford To Drive Business Growth
Dec 11
PRTA: Partnered Pipeline Milestones Will Drive Upside Over Catalyst-Rich Year Ahead
Analysts have lifted their fair value estimate for Prothena by about $2 per share, citing stronger long term revenue growth expectations from its partnered pipeline, lucrative royalty and milestone economics, and a robust catalyst calendar that they believe offers substantial upside potential. Analyst Commentary Recent adjustments to Prothena's valuation reflect a growing conviction that the company’s partnered programs and associated economics could materially enhance long term growth, though execution and timing risks remain key variables for investors.PRTA: Upcoming Partnered Pipeline Milestones Will Drive Substantial Upside Over Next Year
Analysts have increased their price target for Prothena, raising it from $16.50 to $18.33. They cite optimism about the company's partnered pipeline and upcoming catalysts as key drivers for this upward revision.PRTA: Upcoming Pipeline Milestones Will Drive Bullish Momentum Over Next 12 Months
Analysts have increased their price target for Prothena significantly, raising it from $15 to $36. They cite the company's strong partnered pipeline as well as substantial potential from upcoming catalysts and milestone payments.Analysts Maintain Prothena Price Target as Valuation Adjustments Reflect Recent Clinical Results
Analysts have marginally raised their price target for Prothena from $13.00 to $13.00. They cited slight adjustments in discount rate and profit margin assumptions as drivers for the updated valuation.AFFIRM-AL And Alzheimer's Trials Will Unlock New Opportunities
Analysts have raised Prothena's fair value estimate by $1.00 to $13.00, citing improved profit margin forecasts and a slightly lower projected future price-to-earnings ratio. What's in the News Prothena announced results from the Phase 1 ASCENT clinical program for PRX012 in early symptomatic Alzheimer's disease.AFFIRM-AL And Alzheimer's Trials Will Unlock New Opportunities
Prothena’s consensus price target has been revised down to $12.00, reflecting weaker expectations primarily due to a notable decline in net profit margin and a reduced future P/E multiple. What's in the News Prothena reported Phase 1 ASCENT program results for PRX012 in early symptomatic Alzheimer's, showing stable pharmacokinetics, low immunogenicity, significant amyloid reduction, but higher ARIA-E rates compared to FDA-approved antibodies; company plans to seek partnerships for PRX012 and PRX012-TfR.AFFIRM-AL And Alzheimer's Trials Will Unlock New Opportunities
Despite a sharp upward revision in both revenue growth and net profit margin forecasts for Prothena, the consensus analyst price target has significantly decreased from $24.29 to $15.00. What's in the News Phase 1 ASCENT results for PRX012 in early symptomatic Alzheimer's showed promising amyloid plaque reduction and pharmacokinetics, but higher ARIA-E rates than approved therapies; Prothena will seek partnership to advance PRX012 and its preclinical Ab-TfR antibody.The Prothena Corporation plc (NASDAQ:PRTA) Analysts Have Been Trimming Their Sales Forecasts
May 29Prothena: Despite Phase 3 Trial Failure, Other Neurodegenerative Programs In Place
May 27Why Investors Shouldn't Be Surprised By Prothena Corporation plc's (NASDAQ:PRTA) 27% Share Price Plunge
May 22Benign Growth For Prothena Corporation plc (NASDAQ:PRTA) Underpins Stock's 26% Plummet
Apr 02
AFFIRM-AL And Alzheimer's Trials Will Unlock New Opportunities
Successful clinical trials for Birtamimab and Alzheimer's treatments could significantly boost Prothena's revenue through large market opportunities.Prothena Corporation: Multiple Failures Make It Risky
Mar 03Prothena Corporation plc (NASDAQ:PRTA) Just Released Its Yearly Earnings: Here's What Analysts Think
Feb 22Insufficient Growth At Prothena Corporation plc (NASDAQ:PRTA) Hampers Share Price
Jan 24Prothena Surges After Parkinson's Drug Misses Primary Endpoint
Dec 22Prothena (NASDAQ:PRTA) Is In A Good Position To Deliver On Growth Plans
Nov 06Prothena: Delays And Data Uncertainty Undermine Case For Investing (Downgrade)
Oct 18Prothena Corporation plc (NASDAQ:PRTA) Looks Inexpensive After Falling 25% But Perhaps Not Attractive Enough
Oct 02Unpleasant Surprises Could Be In Store For Prothena Corporation plc's (NASDAQ:PRTA) Shares
Jul 26Companies Like Prothena (NASDAQ:PRTA) Are In A Position To Invest In Growth
Jun 19Prothena: Potential For Future Price Drop On Failure Risk Of Late-Stage Trials
Jun 07New Forecasts: Here's What Analysts Think The Future Holds For Prothena Corporation plc (NASDAQ:PRTA)
May 14Prothena: Alzheimer's Data Update In 2024 Could Move The Needle
Feb 23Investors Don't See Light At End Of Prothena Corporation plc's (NASDAQ:PRTA) Tunnel And Push Stock Down 33%
Feb 08Are Investors Undervaluing Prothena Corporation plc (NASDAQ:PRTA) By 32%?
Dec 20Shareholder Returns
| PRTA | US Biotechs | US Market | |
|---|---|---|---|
| 7D | 0% | -1.7% | 0.9% |
| 1Y | 33.5% | 27.7% | 28.2% |
Return vs Industry: PRTA exceeded the US Biotechs industry which returned 27.7% over the past year.
Return vs Market: PRTA exceeded the US Market which returned 28.2% over the past year.
Price Volatility
| PRTA volatility | |
|---|---|
| PRTA Average Weekly Movement | 6.5% |
| Biotechs Industry Average Movement | 10.8% |
| Market Average Movement | 7.1% |
| 10% most volatile stocks in US Market | 16.2% |
| 10% least volatile stocks in US Market | 3.2% |
Stable Share Price: PRTA has not had significant price volatility in the past 3 months compared to the US market.
Volatility Over Time: PRTA's weekly volatility (7%) has been stable over the past year.
About the Company
| Founded | Employees | CEO | Website |
|---|---|---|---|
| 2012 | 67 | Gene Kinney | www.prothena.com |
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.
Prothena Corporation plc Fundamentals Summary
| PRTA fundamental statistics | |
|---|---|
| Market cap | US$572.78m |
| Earnings (TTM) | -US$244.09m |
| Revenue (TTM) | US$9.68m |
60.0x
P/S Ratio-2.4x
P/E RatioIs PRTA overvalued?
See Fair Value and valuation analysisEarnings & Revenue
| PRTA income statement (TTM) | |
|---|---|
| Revenue | US$9.68m |
| Cost of Revenue | US$134.85m |
| Gross Profit | -US$125.17m |
| Other Expenses | US$118.92m |
| Earnings | -US$244.09m |
Last Reported Earnings
Dec 31, 2025
Next Earnings Date
May 07, 2026
| Earnings per share (EPS) | -4.53 |
| Gross Margin | -1,292.52% |
| Net Profit Margin | -2,520.57% |
| Debt/Equity Ratio | 0% |
How did PRTA perform over the long term?
See historical performance and comparisonCompany Analysis and Financial Data Status
| Data | Last Updated (UTC time) |
|---|---|
| Company Analysis | 2026/05/04 23:24 |
| End of Day Share Price | 2026/05/04 00:00 |
| Earnings | 2025/12/31 |
| Annual Earnings | 2025/12/31 |
Data Sources
The data used in our company analysis is from S&P Global Market Intelligence LLC. The following data is used in our analysis model to generate this report. Data is normalised which can introduce a delay from the source being available.
| Package | Data | Timeframe | Example US Source * |
|---|---|---|---|
| Company Financials | 10 years |
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| Analyst Consensus Estimates | +3 years |
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| Market Prices | 30 years |
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| Ownership | 10 years |
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| Management | 10 years |
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| Key Developments | 10 years |
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* Example for US securities, for non-US equivalent regulatory forms and sources are used.
Unless specified all financial data is based on a yearly period but updated quarterly. This is known as Trailing Twelve Month (TTM) or Last Twelve Month (LTM) Data. Learn more.
Analysis Model and Snowflake
Details of the analysis model used to generate this report is available on our Github page, we also have guides on how to use our reports and tutorials on Youtube.
Learn about the world class team who designed and built the Simply Wall St analysis model.
Industry and Sector Metrics
Our industry and section metrics are calculated every 6 hours by Simply Wall St, details of our process are available on Github.
Analyst Sources
Prothena Corporation plc is covered by 24 analysts. 5 of those analysts submitted the estimates of revenue or earnings used as inputs to our report. Analysts submissions are updated throughout the day.
| Analyst | Institution |
|---|---|
| Geoffrey Meacham | Barclays |
| Tazeen Ahmad | BofA Global Research |
| null null | BTIG |