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NASDAQ:PRTA

Prothena (PRTA) Stock Price, News & Analysis

Prothena logo
$11.19 +0.40 (+3.71%)
Closing price 04:00 PM Eastern
Extended Trading
$11.18 -0.01 (-0.09%)
As of 04:34 PM Eastern
Extended trading is trading that happens on electronic markets outside of regular trading hours. This is a fair market value extended hours price provided by Massive. Learn more.

About Prothena Stock (NASDAQ:PRTA)

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Key Stats

Today's Range
$10.89
$11.25
50-Day Range
$8.54
$11.51
52-Week Range
$4.32
$11.69
Volume
306,797 shs
Average Volume
490,086 shs
Market Capitalization
$602.36 million
P/E Ratio
N/A
Dividend Yield
N/A
Price Target
$21.67
Consensus Rating
Hold

Company Overview

Prothena Stock Analysis - MarketRank™

See Top-Rated MarketRank™ Stocks
43rd Percentile Overall Score

PRTA MarketRank™: 

Prothena scored higher than 43% of companies evaluated by MarketBeat, and ranked 573rd out of 854 stocks in the medical sector. Scores are calculated by averaging available category scores, with extra weight given to analysis and valuation.

  • Consensus Rating

    Prothena has received a consensus rating of Hold. The company's average rating score is 2.36, and is based on 1 strong buy rating, 4 buy ratings, 4 hold ratings, and 2 sell ratings.

  • Upside Potential

    Prothena has a consensus price target of $21.67, representing about 96.0% upside from its current price of $11.06.

  • Amount of Analyst Coverage

    Prothena has only been the subject of 3 research reports in the past 90 days.

  • Read more about Prothena's stock forecast and price target.
  • Earnings Growth

    Earnings for Prothena are expected to decrease in the coming year, from $0.69 to ($0.84) per share.

  • Price to Earnings Ratio vs. the Market

    The P/E ratio of Prothena is -2.44, which means that its earnings are negative and its P/E ratio cannot be compared to companies with positive earnings.

  • Price to Earnings Ratio vs. Sector

    The P/E ratio of Prothena is -2.44, which means that its earnings are negative and its P/E ratio cannot be compared to companies with positive earnings.

  • Price to Earnings Growth Ratio

    Prothena has a PEG Ratio of 0.37. PEG Ratios below 1 indicate that a company could be undervalued.

  • Price to Book Value per Share Ratio

    Prothena has a P/B Ratio of 2.12. P/B Ratios below 3 indicates that a company is reasonably valued with respect to its assets and liabilities.

  • Read more about Prothena's valuation and earnings.
  • Percentage of Shares Shorted

    14.67% of the float of Prothena has been sold short.
  • Short Interest Ratio / Days to Cover

    Prothena has a short interest ratio ("days to cover") of 15.33, which indicates bearish sentiment.
  • Change versus previous month

    Short interest in Prothena has recently increased by 0.87%, indicating that investor sentiment is decreasing.
  • Dividend Yield

    Prothena does not currently pay a dividend.

  • Dividend Growth

    Prothena does not have a long track record of dividend growth.

  • News Sentiment

    Prothena has a news sentiment score of 0.13. This score is calculated as an average of sentiment of articles about the company over the last seven days and ranges from 2 (good news) to -2 (bad news). This is a lower news sentiment than the 0.59 average news sentiment score of Medical companies.
  • News Coverage This Week

    MarketBeat has tracked 3 news articles for Prothena this week, compared to 2 articles on an average week.
  • Insider Buying vs. Insider Selling

    In the past three months, Prothena insiders have not sold or bought any company stock.

  • Percentage Held by Insiders

    10.40% of the stock of Prothena is held by insiders. A high percentage of insider ownership can be a sign of company health.

  • Percentage Held by Institutions

    97.08% of the stock of Prothena is held by institutions. High institutional ownership can be a signal of strong market trust in this company.

  • Read more about Prothena's insider trading history.
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PRTA Stock News Headlines

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Jeff Brown predicted Bitcoin before it climbed as high as 52,400%, Tesla before 2,150%, and Nvidia before 32,000%. Now he says SpaceX is shaping up to be the biggest IPO of the decade - and three key milestones just confirmed it. In the past 21 days: SpaceX crossed 10,000 active satellites, Elon filed confidential IPO paperwork with the SEC, and another rocket launched 25 more satellites. Two-thirds of every satellite in orbit now belongs to one company. The public filing could drop any day.tc pixel
Prothena Announces Leadership Team Updates
Prothena (PRTA) Gets a Sell from Bank of America Securities
See More Headlines

PRTA Stock Analysis - Frequently Asked Questions

Prothena's stock was trading at $9.55 on January 1st, 2026. Since then, PRTA stock has increased by 15.8% and is now trading at $11.0550.

Prothena Corporation plc (NASDAQ:PRTA) released its earnings results on Thursday, February, 19th. The biotechnology company reported ($0.44) earnings per share for the quarter, topping the consensus estimate of ($0.45) by $0.01. The biotechnology company had revenue of $0.02 million for the quarter, compared to the consensus estimate of $0.67 million. Prothena had a negative trailing twelve-month return on equity of 65.89% and a negative net margin of 2,520.57%.
Read the conference call transcript
.

Top institutional investors of Prothena include Penbrook Management LLC (0.50%), Focused Wealth Management Inc (0.39%), Hsbc Holdings PLC (0.12%) and CHICAGO TRUST Co NA (0.03%). Insiders that own company stock include William P Scully, Gene G Kinney, Tran Nguyen, Dennis J Selkoe, Wagner M Zago, Brandon S Smith, Carol D Karp, Hideki Garren, Karin L Walker and Michael J Malecek.
View institutional ownership trends
.

Shares of PRTA stock can be purchased through any online brokerage account. Popular online brokerages with access to the U.S. stock market include Charles Schwab, E*TRADE, Fidelity, and Vanguard Brokerage Services.

Based on aggregate information from My MarketBeat watchlists, some other companies that Prothena investors own include Voyager Therapeutics (VYGR), American Water Works (AWK), Humana (HUM), Waste Connections (WCN), The RMR Group (RMR), DiamondRock Hospitality (DRH) and AUO (AUOTY).

Company Calendar

Last Earnings
2/19/2026
Today
5/05/2026
Next Earnings (Estimated)
5/07/2026
Fiscal Year End
12/31/2026

Industry, Sector and Symbol

Stock Exchange
NASDAQ
Sector
Medical
Industry
MED - BIOMED/GENE
Sub-Industry
Pharmaceutical Products
Current Symbol
NASDAQ:PRTA
CIK
1559053
Employees
130
Year Founded
2012

Price Target and Rating

High Price Target
$36.00
Low Price Target
$6.00
Potential Upside/Downside
+93.6%
Consensus Rating
Hold
Rating Score (0-4)
2.36
Research Coverage
11 Analysts

Profitability

EPS (Trailing Twelve Months)
($4.54)
Trailing P/E Ratio
N/A
Forward P/E Ratio
16.22
P/E Growth
0.37
Net Income
-$244.09 million
Net Margins
-2,520.57%
Pretax Margin
-2,073.82%
Return on Equity
-65.89%
Return on Assets
-56.00%

Debt

Debt-to-Equity Ratio
N/A
Current Ratio
7.72
Quick Ratio
7.72

Sales & Book Value

Annual Sales
$9.68 million
Price / Sales
62.23
Cash Flow
N/A
Price / Cash Flow
N/A
Book Value
$5.21 per share
Price / Book
2.15

Miscellaneous

Outstanding Shares
53,830,000
Free Float
48,234,000
Market Cap
$602.36 million
Optionable
Optionable
Beta
-0.23

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This page (NASDAQ:PRTA) was last updated on 5/5/2026 by MarketBeat.com Staff.
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