PRTA Company Profile and Key Details

Q: Who are the executives of PRTA?

Ms. Carol D. KarpChief Regulatory OfficerDr. Hideki Garren M.D., Ph.D.Chief Medical OfficerMs. Karin L. Walker CPA, CPAChief Accounting Officer & ControllerMs. Jennifer ZibudaDirector of Investor Relations & CommunicationMr. Brandon S. SmithChief Operating OfficerMr. Michael J. MalecekChief Legal Officer & Company Sec.Dr. Gene G. Kinney Ph.D.Pres, Chief Executive Officer & DirectorDr. Wagner M. ZagoChief Scientific OfficerMs. Yvonne M. TchrakianCompany Sec.Mr. Tran B. Nguyen M.B.A.Chief Financial Officer & Chief Strategy Officer

NASDAQ : PRTA

Prothena

$9.31

0.58+6.64%

At Close 4:00 PM

60.49

BESG ScoreESG Rating

Profile Key Stats Analyst Ratings Ownership Ratios Financials Dividend & splits Sentiment Forecast

Price Chart

Stock Price Today

Prothena Corporation plc (PRTA) stock surged +6.64%, trading at $9.31 on NASDAQ, up from the previous close of $8.73. The stock opened at $8.84, fluctuating between $8.84 and $9.31 in the recent session.

Stock Snapshot

8.73

Prev. Close

501.19M

Market Cap

8.84

Day Low

-2.06

P/E Ratio

-4.53

EPS (TTM)

-2.55

Cash Flow per Share

8.84

Open

53.83M

Number of Shares

9.31

Day High

74.48%

Free Float in %

10.46

Book Value

543.66K

Volume

Relevant Articles

SEC Fillings

Current Report (8-k)

Filing Date	Accepted Date

Annual Report (10-k)

Filing Date	Accepted Date

Stock Price History Chart

Date	Open	High	Low	Close	Volume
Mar 25, 2026	8.84	9.32	8.82	9.31	540.09K
Mar 24, 2026	8.75	8.96	8.49	8.73	534.73K
Mar 23, 2026	8.83	9.04	8.76	8.82	487.38K
Mar 20, 2026	8.54	8.76	8.44	8.75	1.39M
Mar 19, 2026	8.54	8.62	8.38	8.54	459.89K
Mar 18, 2026	8.94	8.94	8.53	8.59	495.88K
Mar 17, 2026	9.10	9.20	8.96	9.00	467.13K
Mar 16, 2026	9.27	9.31	9.08	9.17	476.38K
Mar 13, 2026	9.40	9.54	8.99	9.21	574.56K
Mar 12, 2026	9.48	9.48	9.09	9.31	723.31K
Mar 11, 2026	9.70	9.84	9.26	9.58	689.45K
Mar 10, 2026	10.21	10.27	9.68	9.77	628.26K
Mar 09, 2026	9.27	9.95	9.22	9.81	624.22K
Mar 06, 2026	9.24	9.64	9.24	9.59	623.76K
Mar 03, 2026	9.09	9.62	8.95	9.36	551.77K
Mar 02, 2026	9.09	9.61	8.97	9.40	784.77K
Feb 27, 2026	8.53	8.79	8.48	8.67	402.3K
Feb 26, 2026	8.88	8.96	8.63	8.64	353.59K
Feb 25, 2026	9.00	9.11	8.53	8.88	481.12K
Feb 24, 2026	9.03	9.30	8.75	8.97	448.81K

Contact Details

Dublin, 2

Ireland

https://www.prothena.com 353 123 62500

About Company

Prothena Corporation plc, a late-stage clinical company, focuses on discovery and development of novel therapies for life-threatening diseases in the United States. The company is involved in developing Birtamimab, an investigational humanized antibody that is in Phase III clinical trial for the treatment of AL amyloidosis; Prasinezumab, a humanized monoclonal antibody, which is in Phase IIb clinical trial for the treatment of Parkinson's disease; PRX004 that completed Phase I clinical trial for the treatment of Transthyretin amyloidosis; and PRX005, which is in Phase I clinical trial for the treatment of Alzheimer's disease. Its discovery and preclinical programs include PRX012 for the treatment of Alzheimer's disease; and dual A�-Tau vaccine for the treatment and prevention of Alzheimer's disease. Prothena Corporation plc has a license, development, and commercialization agreement with F. Hoffmann-La Roche Ltd. and Hoffmann-La Roche Inc. to develop and commercialize antibodies that target alpha-synuclein; and a collaboration agreement with Bristol-Myers Squibb to develop antibodies. The company was founded in 2012 and is based in Dublin, Ireland.

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Seagen Inc.$228.74

Company Overview

Prothena Corporation plc (NASDAQ:PRTA) closed at $9.31 USD, gaining $0.58 (6.64%) from the previous close of $8.73. The stock is currently mid-range between its 52-week high and low $4.32 and $13.71. With a market capitalization of about $501.19 million, Prothena Corporation plc is classified as a small-cap and shows lower-than-market volatility (beta ~-0.28). Key stats such as the average daily volume over the past year has been around 506.98 thousand shares, in line with its 52-week average. Headquartered in Dublin, None, Prothena Corporation plc operates in the Healthcare sector and the Biotechnology industry. Led by CEO Gene G. Kinney, the company employs approximately 163 people and listed since December 18, 2012. Prothena Corporation plc, a late-stage clinical company, focuses on discovery and development of novel therapies for life-threatening diseases in the United States.

Technical Performance

PRTA has shown mixed momentum, gaining 3.82% over the past week and -6.75% over the past quarter, though year-to-date performance is down -3.14%. Short-term trend indicators are mixed aligned (SMA20 -2.88%, SMA50 -6.26%, SMA200 2.32%). The stock’s 14-day RSI is 39.57 (weak momentum), while the ATR of 0.52 points to higher daily volatility. The stock remains hovering near 52-week lows, trading -46.53% below its high and over 100.0% above its low. Average 10-day trading volume of 606.88 thousand shares is slightly above the 3-month average of 503.83 thousand, indicating heightened recent market interest.

Valuation Metrics

Prothena Corporation plc trades at a P/E ratio of -1.98, slightly below the S&P 500 average, with a price-to-sales ratio of 49.98 and a price-to-book ratio of 1.73 suggesting the stock is closer to book value. The P/FCF stands at -2.89, also below market averages.

Dividend & Fair Value

Prothena Corporation plc last paid a dividend of 0 per share, Dividend and splits history remains an important factor for investors monitoring long-term returns. A discounted cash flow model estimates fair value at around $3.22. This means the shares are trading above this model’s fair value.

Earnings & Analyst Outlook

Prothena Corporation plc generated EPS of -$4.53 over the past year. Five-year average earnings growth is -10.24%. The latest quarter delivered EPS of -$0.67. The next quarter is forecast at -$0.35. Next year's EPS is expected at -$53.80. Analyst sentiment is bullish. Analyst rating data shows there are 4 Strong Buy ratings, 5 Buy ratings, 3 Hold ratings, 0 Sell rating and 1 Strong Sell ratings. Price targets range from $36.00 to $4.00. The high target offers 286.68% upside. The low target suggests -57.04% downside. The mean target is $16.77. This offers 80.13% upside. Prothena Corporation plc earnings surprise history is a mixed track record. The quarter that ended November 06, 2025, missed forecasts by 11.67%. The prior quarter beat by 67.57%. Over the last six quarters, Apple has recorded several small beats. These include -220.79% in August 08, 2024.

Shareholding & Insider Activity

Prothena Corporation plc has 53.83 million shares outstanding. The public float is 40.09 million shares, elevated short interest at 14.62% of float. This equals 4.18 million shares. The short ratio is 4.11 days. Institutional investors hold 97.94% of the float. Insiders own 18.66%. EcoR1 Capital, LLC holds 5.30 million shares, SCULLY WILLIAM P has 735.99 thousand shares and Kinney Gene G. has 12.79 thousand shares.

Financial & Profitability Overview

Over the trailing twelve months, Prothena generated $91.37M in revenue, or $1.72 per share. Gross margin was 90.79%, operating margin -209.08%, and net profit margin -160.91%. Returns are negative, with ROA at -21.11% and ROE at -26.19%.
On valuation metrics, Prothena trades at a P/E of -1.98, P/S of 49.98 and P/B of 1.73. The current ratio is 7.72 and quick ratio is 7.72. Operationally, the company’s inventory turnover is 0.00 and cash conversion cycle is -71.77 days , indicating it collects cash faster than it pays suppliers. Debt-to-equity is 0.05, supported by a cash flow-to-debt ratio of -12.08.

Quarterly Financial Highlights

For the quarter ended Dec 31, 2023, Prothena posted revenue of $91.37M, down slightly from $53.91M in the prior quarter. Gross profit was $82.96M (margin 90.79%). Operating income was - $191.04M (margin -209.1%). Net income was- $147.03M (EPS - $2.76).
The company ended the quarter with $620.18M in cash and short-term investments, a total debt of $11.84M, and net debt of - $608.35M. Total assets were $696.38M, with equity of $561.37M. Financials further reflected weakness, with operating cash flow of - $133.91M, free cash flow of - $136.72M, and capital expenditures of - $2.81M.

Price Forecast & Outlook

Our AI price prediction model suggests that Prothena Corporation plc stock has strong potential for upside but may face short-term weakness followed by gains in the medium and long term. 2-Week Outlook: Projected decline of -16.97%, with price expected at $7.73 by April 07, 2026, within a range of $7.45 to $8.01 3-Month Outlook: Projected fall of -52.63%, reaching $4.41 by June 22, 2026, with a range of $3.92 to $4.82. 1-Year Outlook: Projected gain of 176.58%, with price at $25.75 by March 24, 2027, within a range of $11.39 to $38.01.

Key Takeaways

Prothena Corporation plc (NASDAQ:PRTA) shares are flat -3.14% year-to-date currently trading near 52-week highs band. Short-term momentum has been negative over the last quarter, despite recent volatility. Valuation shows Prothena Corporation plc trading at a premium to the broader market with a P/E of -1.98. Analyst sentiment is cautious, with the majority of ratings in Sector Perform territory and a mean price target of $56.70, suggesting 509.02% upside. Our AI forecast model points to short-term weakness (-16.97% over two weeks), a medium-term fall (-52.63% over three months), and a longer-term gain (176.58% over one year), with expected trading ranges indicating moderate volatility.

Frequently Asked Questions

What is the current Prothena Corporation plc (PRTA) stock price?

Prothena Corporation plc (NASDAQ: PRTA) stock price is $9.31 in the last trading session. During the trading session, PRTA stock reached the peak price of $9.31 while $8.84 was the lowest point it dropped to. The percentage change in PRTA stock occurred in the recent session was 6.64% while the dollar amount for the price change in PRTA stock was $0.58.

PRTA's industry and sector of operation?

The NASDAQ listed PRTA is part of Biotechnology industry that operates in the broader Healthcare sector. Prothena Corporation plc designs, manufactures, and markets smartphones, personal computers, tablets, wearables, and accessories worldwide.

Who are the executives of PRTA?

Ms. Carol D. Karp
Chief Regulatory Officer
Dr. Hideki Garren M.D., Ph.D.
Chief Medical Officer
Ms. Karin L. Walker CPA, CPA
Chief Accounting Officer & Controller
Ms. Jennifer Zibuda
Director of Investor Relations & Communication
Mr. Brandon S. Smith
Chief Operating Officer
Mr. Michael J. Malecek
Chief Legal Officer & Company Sec.
Dr. Gene G. Kinney Ph.D.
Pres, Chief Executive Officer & Director
Dr. Wagner M. Zago
Chief Scientific Officer
Ms. Yvonne M. Tchrakian
Company Sec.
Mr. Tran B. Nguyen M.B.A.
Chief Financial Officer & Chief Strategy Officer

How PRTA did perform over past 52-week?

PRTA's closing price is 115.51% higher than its 52-week low of $4.32 where as its distance from 52-week high of $13.71 is -32.09%.

How many employees does PRTA have?

Number of PRTA employees currently stands at 163.

Link for PRTA official website?

Official Website of PRTA is: https://www.prothena.com

How do I contact PRTA?

PRTA could be contacted at phone 353 123 62500 and can also be accessed through its website. PRTA operates from 77 Sir John Rogerson’s Quay, Dublin, 2, Ireland.

How many shares of PRTA are traded daily?

PRTA stock volume for the day was 543.66K shares. The average number of PRTA shares traded daily for last 3 months was 506.98K.

What is the market cap of PRTA currently?

The market value of PRTA currently stands at $501.19M with its latest stock price at $9.31 and 53.83M of its shares outstanding.

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Employees	163
Beta	-0.28
Sales or Revenue	$91.37M
5Y Sales Change%	70.122%
Fiscal Year Ends	December
Sector	Healthcare
Industry	Biotechnology

PRTA Company Profile and Key Details

Prothena

Price Chart

Stock Price Today

Stock Snapshot

Relevant Articles

SEC Fillings

Current Report (8-k)

Annual Report (10-k)

Stock Price History Chart

Contact Details

About Company

Company Information

Stock Peers

Company Overview

Technical Performance

Valuation Metrics

Dividend & Fair Value

Earnings & Analyst Outlook

Shareholding & Insider Activity

Financial & Profitability Overview

Quarterly Financial Highlights

Price Forecast & Outlook

Key Takeaways

Frequently Asked Questions

Technical Performance

Dividend & Fair Value

Earnings & Analyst Outlook

Company Overview

Shareholding & Insider Activity

Financial & Profitability Overview

Quarterly Financial Highlights

Valuation Metrics

Key Takeaways

Price Forecast & Outlook