Prothena share price logo

Prothena

NASDAQ: PRTA

Small Cap

$9.62

+0.01

(+0.05%)

Live

as on

Prothena Stock Performance

as on September 3, 2026 at 6:25 am IST

  • Day's Low

    Day's High

    $9.37
    $9.75
    downward going graph

    2.60%

    Downside

    1.35%

    Upside

    downward going graph

  • 52 Week's Low

    52 Week's High

    $7.73
    $11.80
    downward going graph

    19.65%

    Downside

    22.66%

    Upside

    downward going graph

Prothena share price movements today

Previous Close
$9.61
Open
$9.64
Volume
283.4K
Market Cap
$493.3M
Day's Low - High
$9.37 - $9.75
52 Week Low - High
$7.73 - $11.80

Prothena Historical Returns

1 Month Return
+ 18.35 %
3 Month Return
+ 4.57 %
1 Year Return
+ 16.2 %
3 Year Return
-82.57 %
5 Year Return
-86.64 %

Prothena Stock Fundamentals & Key Indicators

Check Prothena market cap, PE, PB, PEG ratios, dividend yield, and other key fundamental indicators.

Market Cap

$493.3M

EPS (TTM)

-0.83

Dividend Yield

0.00%

Quarterly Earnings Growth YOY

0.00%

PE Ratio (TTM)

-10.94

Industry PE ratio

-6.724375

PEG Ratio

-0.05884718154904193

EBITDA

-41.1M

Revenue (TTM)

54.5M

Profit Margin

43.52%

Return On Equity TTM

-14.98%

Prothena Stock Valuation

Track how Prothena P/E has moved over time to understand its valuation trends.

Prothena in the last 5 years

  • Overview

  • Trends

Lowest (-24.40x)

December 31, 2022

Industry (-6.72x)

December 31, 2025

Today (-2.11x)

December 31, 2025

Highest (32.62x)

December 31, 2021

LowHigh

Today’s Price to Earnings Ratio: -2.11x

Prothena vs Peer Comparison

Compare market cap, revenue, PE, and other key metrics of Prothena with its industry peers.

Company
Analyst View
Market Cap
5 Years Return %PE RatioProfit Margin %Dividend Yield %
Prothena image
Prothena
BUY$493.3M-86.64%-10.9443.52%NA
Revolution Medicines image
Revolution Medicines
BUY$44.6B614.61%NA0.00%NA
Vertex Pharmaceuticals image
Vertex Pharmaceuticals
BUY$137.9B174.9%31.9286.04%NA
Moderna image
Moderna
BUY$61.6B-61.21%-7.98-12.57%NA
Regeneron image
Regeneron
BUY$82.3B21.91%19.984.86%0.44%

Stock Returns calculator for Prothena Stock including INR - Dollar returns

The Prothena stock calculator helps Indian investors calculate returns based on the historical performance of the stock. Just choose your investment amount and duration to get insights and invest more confidently. See stock returns as well as the effect of dollar appreciation over different durations.

*Dollar Impact: The bonus return you make when the US Dollar rises against the Rupee; calculated on the full amount you walk away with, not just what you invested in.

Investment Value

₹1,00,000

  • 1Y

  • 3Y

  • 5Y

  • 7Y

  • 10Y

Prothena investment value today

Current value as on today

₹1,25,527

Returns

₹25,527

(+25.53%)

Returns from Prothena Stock

₹16,324 (+16.32%)

Dollar Impact

₹9,203 (+9.2%)

Analyst Recommendation on Prothena Stock

Based on 4 analysts

BUY

50.00%

Buy

25.00%

Hold

25.00%

Sell

Based on 4 analysts, 50% of analysts recommend a 'BUY' rating for Prothena. Average target price of $21.4

Prothena Share Price Target

Get share price movements and forecasts by analysts on Prothena.

What analysts predicted

55.05%UPSIDE

Target Price

$21.4

Current Price

$9.62

Analyzed by

4 Analysts

Target

$21.40

Prothena target price $21.4, a slight upside of 55.05% compared to current price of $9.62. According to 4 analysts rating.

Indian Investors' Interest in Prothena Stock

Search interest for Prothena Stock has decreased by -36% in the last 30 days, reflecting a downward trend in search activity.

Time period: to

Change:-36% versus previous 30 day period

Prothena Quarterly Profit & Loss

All numbers in Millions USD

Mar 2024
Jun 2024
Sep 2024
Dec 2024
Mar 2025
Jun 2025
Sep 2025
Dec 2025
Mar 2026
Jun 2026
Total Revenue
0
132
0
2
2
4
2
0
51
1
Gross Profit
0
132
0
2
2
4
-26
0
50
1
Operating Income
-81
58
-66
-64
-65
-84
-40
-27
25
-21
EBITDA
-74
65
-59
-59
-61
-51
-35
-20
33
-18
Interest Expense
-
-
-
-
-
-
-
-
-
-
Depreciation
0
0
0
0
0
0
0
0
0
0
Income Before Tax
-74
64
-59
-59
-61
-80
-36
-21
32
-18
Income Tax Expense
-2
-2
0
-1
-1
44
0
0
0
0
Net Income
-72
66
-59
-57
-60
-125
-36
-21
32
-18
Net Profit Margin
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
-1098.26%
-4385.71%
98.20%
100.00%

Prothena Annual Profit & Loss

All numbers in Millions USD

Dec 2017
Dec 2018
Dec 2019
Dec 2020
Dec 2021
Dec 2022
Dec 2023
Dec 2024
Dec 2025
Total Revenue
27
0
0
0
200
53
91
135
9
Gross Profit
-107
-100
-50
-74
200
53
91
135
5
Operating Income
-155
-158
-85
-112
71
-131
-191
-154
-184
EBITDA
-152
-152
-84
-111
73
-124
-159
-128
-197
Interest Expense
3
3
-
-
-
-
-
-
-
Depreciation
3
3
1
1
1
0
0
0
3
Income Before Tax
-157
-156
-77
-110
71
-125
-160
-128
-200
Income Tax Expense
-4
0
0
0
4
-8
-13
-6
43
Net Income
-153
-155
-77
-111
66
-116
-147
-122
-244
Net Profit Margin
-388.92%
-10495.08%
-6145.21%
-8678.90%
100.00%
100.00%
100.00%
100.00%
61.77%

Prothena Quarterly Cash Flow

All numbers in Millions USD

Mar 2024
Jun 2024
Sep 2024
Dec 2024
Mar 2025
Jun 2025
Sep 2025
Dec 2025
Mar 2026
Jun 2026
Net Income
-72
66
-59
-57
-60
-125
-36
-21
32
-18
Operating Cash Flow
-73
15
-45
-47
-53
-46
-40
-23
28
-25
Investing Cash Flow
0
0
0
0
0
0
0
-
-
0
Financing Cash Flow
0
0
0
0
0
0
0
-
-6
-15
Change in Cash
-72
16
-44
-47
-53
-46
-40
-23
21
-41

Prothena Annual Cash Flow

All numbers in Millions USD

Dec 2017
Dec 2018
Dec 2019
Dec 2020
Dec 2021
Dec 2022
Dec 2023
Dec 2024
Dec 2025
Net Income
-153
-155
-77
-111
66
-116
-147
-122
-244
Operating Cash Flow
-131
-28
-52
-80
92
-108
-133
-150
-163
Investing Cash Flow
-3
-1
0
0
0
0
-2
0
0
Financing Cash Flow
165
40
0
0
190
241
45
1
0
Change in Cash
30
10
-53
-80
282
132
-91
-148
-163

Mutual Funds that own Prothena Stock

Check out the Mutual Funds with significant holdings in Prothena.

Funds
Holdings
Shares Held
Fidelity Mt. Vernon Street Trust
6.783913%
3482656
TIAA-CREF Funds
1.728841%
887535
Fidelity Select Portfolios
1.254294%
643917
VANGUARD EXPLORER FUND
1.202295%
617222
Federated Hermes MDT Series
1.073473%
551089
See all

Global Institutional Holdings in Prothena

Funds
Holdings
iShares
4.22%
SPDR
3.42%
Vanguard
1.77%
Dimensional
0.79%
Schwab
0.43%
See all

Insights on Prothena

Insights help you understand the recent movement of the company's critical parameters, giving you an overall view of the company.

  • imgPOSITIVE IMPACT

    Price Rise

    img

    In the last 7 days, PRTA stock has moved up by 3.9%

  • imgNO EFFECT

    Against Peers

    img

    In the last 1 year, Moderna, Inc. Common Stock has given 537.7% return, outperforming this stock by 521.5%

  • imgNO EFFECT

    Against Peers

    img

    In the last 3 years, Revolution Medicines, Inc. Common Stock has given 37.1% return, outperforming this stock by 119.7%

  • imgNEGATIVE IMPACT

    Revenue Fall

    img

    Revenue is down for the last 2 quarters, 51.08M → 1.01M (in $), with an average decrease of 98.0% per quarter

  • imgNEGATIVE IMPACT

    Profit Down

    img

    Netprofit is down for the last 2 quarters, 32.72M → -18.58M (in $), with an average decrease of 156.8% per quarter

About Prothena

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. In addition, it develops discovery- and late-preclinical-stage programs include TDP-43 CYTOPE for the treatment of amyotrophic lateral sclerosis; PRX012, a next-generation anti-Aß antibody which is in phase 1 clinical trial to treat Alzheimer's disease; and PRX012-TfR, a preclinical program for the treatment of Alzheimer's disease. It 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 master collaboration agreement with Bristol Myers Squibb to develop and commercialize antibodies targeting tau, TDP-43. Prothena Corporation plc was incorporated in 2012 and is based in Dublin, Ireland.
OrganisationProthena
Headquarters77 Sir John Rogerson?s Quay, Dublin, Ireland, D02 VK60
IndustryBiotechnology
CEODr. Gene G. Kinney Ph.D.
E-voting on sharesClick here to vote

Key Management of Prothena

Name

Title

Mr. Mark C. Johnson C.F.A.

Vice President of Investor Relations

Mr. Michael J. Isaacs

General Counsel & Corporate Secretary

Phillip Dolan

Sr. Director & Head of Exploratory Research

Ms. Annie Evans Kingston

Chief Strategy Officer

Mr. Brandon S. Smith

Chief Operating Officer

Dr. Wagner M. Zago Ph.D.

Chief Scientific Officer

Dr. Chad H. Swanson Ph.D.

Chief Development Officer

Ms. Karin L. Walker CPA

Chief Accounting Officer & Controller

Dr. Gene G. Kinney Ph.D.

President, CEO & Director

Mr. Tran B. Nguyen M.B.A.

Chief Financial Officer

FAQs

What is Prothena share price today?

Prothena share price today is $9.62 as on . Prothena share today touched a day high of $9.75 and a low of $9.37.

What is the 52 week high and 52 week low for Prothena share?

Prothena share touched a 52 week high of $11.80 on and a 52 week low of $7.73 on . Prothena stock price today i.e. is trending at $9.62,which is 18.47% down from its 52 week high and 24.45% up from its 52 week low.

What is Prothena's market capitalisation today?

Prothena market capitalisation is $0.00T as on .

How to invest in Prothena Stock (PRTA) from India?

  1. Step 1: Open a free US stocks account on INDmoney App and transfer your Rupees into Dollars to your INDmoney US stocks account. For a step by step instruction, check How to Transfer Money to Your US Stocks Account .
  2. Step 2: Search for Prothena on INDmoney app. Click on Buy button. You can invest as low as $1.5 in Prothena Shares that will get you 0.1559 shares as per Prothena share price of $9.62 per share as on September 3, 2026 at 12:55 am IST.

What is the minimum amount required to buy Prothena Stock (PRTA) from India?

Indian investors can start investing in Prothena (PRTA) shares with as little as ₹94.96 or $1 (as of ) using the INDmoney app.
For example: If you want to invest $10 or ₹949.60 in Prothena stock (as per the Rupee-Dollar exchange rate as on ). Based on Prothena share’s latest price of $9.62 as on September 3, 2026 at 12:55 am IST, you will get 1.0395 shares of Prothena. Learn more about fractional shares .

What are the returns that Prothena has given to Indian investors in the last 5 years?

Prothena stock has given -86.64% share price returns and 30.36% dollar appreciation to an Indian investor in the last 5 years.
Read more about How do Currency Exchange Rates impact your returns on US Stock Investments?