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NASDAQ:PRTA

Prothena (PRTA) Stock Price, News & Analysis

Prothena logo
$5.72 -0.03 (-0.52%)
Closing price 06/20/2025 04:00 PM Eastern
Extended Trading
$5.83 +0.11 (+1.91%)
As of 06/20/2025 07:46 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 Polygon.io. Learn more.

About Prothena Stock (NASDAQ:PRTA)

Key Stats

Today's Range
$5.64
$6.05
50-Day Range
$4.58
$9.94
52-Week Range
$4.32
$25.42
Volume
3.57 million shs
Average Volume
765,891 shs
Market Capitalization
$307.89 million
P/E Ratio
N/A
Dividend Yield
N/A
Price Target
$31.50
Consensus Rating
Hold

Company Overview

Prothena Corporation plc, a late-stage clinical biotechnology company, focuses on discovery and development of novel therapies to treat diseases caused by protein dysregulation 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, for the treatment of Parkinson's disease and other related synucleinopathies which is in Phase IIb clinical trial; NNC6019 that is in Phase lI clinical trial for the treatment of ATTR amyloidosis; and BMS-986446 and PRX012, which is in Phase I clinical trial for the treatment of Alzheimer's disease. Its discovery and preclinical programs include PRX123, a dual Aß-Tau vaccine for the treatment and prevention of Alzheimer's disease; and PRX019 for the treatment of neurogenerative diseases, as well as TDP-43 for the treatment of amyotrophic lateral sclerosis. 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 a-synuclein, including prasinezumab; and a collaboration agreement with Bristol-Myers Squibb to develop and commercialize antibodies targeting tau, TDP-43. The company was incorporated in 2012 and is based in Dublin, Ireland.

Prothena Stock Analysis - MarketRank™

See Top-Rated MarketRank™ Stocks
72nd Percentile Overall Score

PRTA MarketRank™: 

Prothena scored higher than 72% of companies evaluated by MarketBeat, and ranked 270th out of 926 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 2.33, and is based on 4 buy ratings, 4 hold ratings, and 1 sell rating.

  • Amount of Analyst Coverage

    Prothena has been the subject of 8 research reports in the past 90 days, demonstrating strong analyst interest in this stock.

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

    Earnings for Prothena are expected to grow in the coming year, from ($4.04) to ($3.33) per share.

  • Price to Earnings Ratio vs. the Market

    The P/E ratio of Prothena is -2.75, 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 -2.75, which means that its earnings are negative and its P/E ratio cannot be compared to companies with positive earnings.

  • Price to Book Value per Share Ratio

    Prothena has a P/B Ratio of 0.63. P/B Ratios below 1 indicate that a company could be undervalued with respect to its assets and liabilities.

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

    10.42% 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 3.3, which is generally considered an acceptable ratio of short interest to trading volume.
  • Change versus previous month

    Short interest in Prothena has recently decreased by 50.73%, indicating that investor sentiment is improving significantly.
  • Dividend Yield

    Prothena does not currently pay a dividend.

  • Dividend Growth

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

  • Percentage of Shares Shorted

    10.42% 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 3.3, which is generally considered an acceptable ratio of short interest to trading volume.
  • Change versus previous month

    Short interest in Prothena has recently decreased by 50.73%, indicating that investor sentiment is improving significantly.
  • News Sentiment

    Prothena has a news sentiment score of 0.44. 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 0.65 average news sentiment score of Medical companies.
  • News Coverage This Week

    MarketBeat has tracked 10 news articles for Prothena this week, compared to 4 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

    Only 9.20% of the stock of Prothena is held by insiders.

  • 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

Prothena (NASDAQ:PRTA) Earns Neutral Rating from Cantor Fitzgerald
New Rule Hits in July — The Smart Money Already Moved
A little-known regulation quietly goes into effect this July. And it's already being exploited by Wall Street and the Big Banks… It gives them the green light to treat a certain tangible asset as equivalent to cold, hard cash. Not stocks. Not real estate. And definitely not the U.S. dollar. We're talking about something they don't want you to notice — because the fewer people who act on this, the better it is for them.
Prothena Announces Corporate Restructuring
See More Headlines

PRTA Stock Analysis - Frequently Asked Questions

Prothena's stock was trading at $13.85 on January 1st, 2025. Since then, PRTA stock has decreased by 58.7% and is now trading at $5.72.
View the best growth stocks for 2025 here
.

Prothena Corporation plc (NASDAQ:PRTA) posted its quarterly earnings data on Thursday, May, 8th. The biotechnology company reported ($1.12) EPS for the quarter, missing the consensus estimate of ($0.92) by $0.20. The firm's quarterly revenue was up 5500.0% compared to the same quarter last year.

Prothena's top institutional investors include Wellington Management Group LLP (9.66%), Price T Rowe Associates Inc. MD (6.42%), Armistice Capital LLC (4.08%) and Palo Alto Investors LP (3.08%). Insiders that own company stock include William P Scully, Gene G Kinney, Tran Nguyen, Dennis J Selkoe, Richard T Collier, Lars Ekman, Karin L Walker, Hideki Garren, Brandon S Smith, Carol D Karp, Wagner M Zago 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 AU Optronics (AUOTY).

Company Calendar

Last Earnings
5/08/2025
Today
6/21/2025
Next Earnings (Estimated)
8/06/2025
Fiscal Year End
12/31/2025

Industry, Sector and Symbol

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

Price Target and Rating

Average Stock Price Target
$31.50
High Stock Price Target
$81.00
Low Stock Price Target
$6.00
Potential Upside/Downside
+450.7%
Consensus Rating
Hold
Rating Score (0-4)
2.33
Research Coverage
9 Analysts

Profitability

Trailing P/E Ratio
N/A
Forward P/E Ratio
N/A
P/E Growth
N/A
Net Income
-$122.31 million
Pretax Margin
-84.00%

Debt

Sales & Book Value

Annual Sales
$137.94 million
Price / Cash Flow
N/A
Book Value
$9.05 per share
Price / Book
0.63

Miscellaneous

Free Float
48,875,000
Market Cap
$307.89 million
Optionable
Optionable
Beta
-0.08
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This page (NASDAQ:PRTA) was last updated on 6/21/2025 by MarketBeat.com Staff
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