Symbols / PRTA Stock $10.77 +0.37% Prothena Corporation plc

Healthcare • Biotechnology • Ireland • NMS
PRTA (Stock) Chart
O: — H: — L: — C: — V: —
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Stock Fundamentals
Scroll to Statements
Index EQUITY
Sector Healthcare
Industry Biotechnology
CEO Dr. Gene G. Kinney Ph.D.
Exch · Country NMS · Ireland
Market Cap 579.78M
Enterprise Value 278.47M
Income -244.09M
Sales 9.68M
FCF (ttm) -78.53M
Book/sh 5.21
Cash/sh 5.71
Employees 67
Insider 10d —
IPO Dec 18, 2012
Div forward ($/yr)
Div TTM ($/yr)
Dividend Yield
Ex-Div Date
5Y Avg Yield
Yield vs 5Y Avg
Payout 0.00%
P/E —
Forward P/E -10.36
PEG —
P/S 59.87
P/B 2.07
P/C —
EV/EBITDA -1.52
EV/Sales 28.76
Quick Ratio 7.53
Current Ratio 7.72
Debt/Eq 2.98
LT Debt/Eq —
EPS (ttm) -4.53
EPS next Y -1.04
EPS Growth —
Revenue Growth -99.00%
EPS Gr Q/Q —
Rev Gr Q/Q —
Earnings (next) 2026-05-07
Earnings (prior) 2026-02-19
ROA -26.40%
ROE -63.62%
ROIC —
Gross Margin 0.00%
Oper. Margin -1,295.76%
Profit Margin 0.00%
Shs Outstand 53.83M
Shs Float 39.65M
Insider Own 19.32%
Instit Own 89.19%
Short Float 15.55%
Short Ratio 11.77
Short Interest 7.02M
52W High 11.69
vs 52W High -7.87%
52W Low 4.32
vs 52W Low 149.31%
Beta -0.33
Impl. Vol. 29.60%
Rel Volume 0.11
Avg Volume 489.12K
Volume 52.79K
Target (mean) $21.00
Tgt Median $19.00
Tgt Low $8.00
Tgt High $36.00
# Analysts 5
Recom None
Prev Close $10.73
Price $10.77
Change 0.37%
About

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.

Valuation Models

Price estimates from analyst targets and simple models.

1. Analyst consensus
$21.00
Mean price target
2. Current target
$10.77
Latest analyst target
3. DCF / Fair value
$-26.26
Simplified: (Free Cash Flow ÷ Shares) × 18 (P/FCF multiple). Not a …
Ratings
Current target
$10.77
Low
$8.00
High
$36.00
Mean
$21.00

Latest analyst rating changes

Date Action Analyst Rating Change Price Target
2026-02-20 main RBC Capital Sector Perform → Sector Perform $12
2025-12-01 main Citizens Market Outperform → Market Outperform $19
2025-11-07 main HC Wainwright & Co. Buy → Buy $30
2025-11-07 main RBC Capital Sector Perform → Sector Perform $11
2025-10-28 main Piper Sandler Overweight → Overweight $36
2025-10-07 main HC Wainwright & Co. Buy → Buy $20
2025-09-02 main JMP Securities Market Outperform → Market Outperform $11
2025-08-28 main Piper Sandler Overweight → Overweight $15
2025-08-28 main Chardan Capital Buy → Buy $18
2025-08-05 main RBC Capital Sector Perform → Sector Perform $10
2025-08-05 reit HC Wainwright & Co. Buy → Buy $14
2025-08-05 main Chardan Capital Buy → Buy $18
2025-06-20 reit Cantor Fitzgerald Neutral → Neutral —
2025-05-28 down B of A Securities Neutral → Underperform $4
2025-05-27 down Oppenheimer Outperform → Perform —
2025-05-27 main Piper Sandler Overweight → Overweight $81
2025-05-27 main JMP Securities Market Outperform → Market Outperform $29
2025-05-27 main Chardan Capital Buy → Buy $18
2025-05-27 main HC Wainwright & Co. Buy → Buy $14
2025-05-09 main HC Wainwright & Co. Buy → Buy $30
News
RSS: Latest PRTA news
Insider Transactions
Filed Date Insider Relationship Transaction Shares Price Value SEC
2025-07-28 KINNEY GENE G PH.D. Chief Executive Officer — 140,000 $0.00 $0
2025-07-28 ZAGO WAGNER M Officer — 85,000 $0.00 $0
2025-07-28 MALECEK MICHAEL J. Officer — 80,000 $0.00 $0
2025-07-28 SMITH BRANDON S Chief Operating Officer — 130,000 $0.00 $0
2025-07-28 SWANSON CHAD PH.D. Officer — 85,000 $0.00 $0
2025-07-28 WALKER KARIN LORRAINE Officer — 25,000 $0.00 $0
2025-07-28 NGUYEN TRAN BRYAN Chief Financial Officer — 95,000 $0.00 $0
2025-05-06 ECOR1 CAPITAL, L.L.C. Beneficial Owner of more than 10% of a Class of Security — 6,279,684 $7.64 $50,839,807
2025-01-15 SCULLY WILLIAM P Beneficial Owner of more than 10% of a Class of Security — 747,700 $0.00 $0
2025-01-14 SCULLY WILLIAM P Beneficial Owner of more than 10% of a Class of Security — 207,436 $12.79 $2,749,916
Financials
Statement View
Amounts in millions (2 decimals, no suffix) • EPS per share (2 decimals) • Trend = period evolution • YoY Growth = previous period %
Line Item Trend 2025-12-31 2024-12-31 2023-12-31 2022-12-31
Total Revenue
9.68
-92.83%
135.16
+47.92%
91.37
+69.50%
53.91
Operating Revenue
9.68
-92.83%
135.16
+47.92%
91.37
+69.50%
53.91
Operating Expense
194.24
-32.95%
289.72
+2.59%
282.41
+52.27%
185.46
Research And Development
134.85
-39.40%
222.52
+0.88%
220.57
+62.71%
135.56
Selling General And Administration
59.39
-11.62%
67.20
+8.67%
61.84
+23.92%
49.90
General And Administrative Expense
59.39
-11.62%
67.20
+8.67%
61.84
+23.92%
49.90
Other Gand A
59.39
-11.62%
67.20
+8.67%
61.84
+23.92%
49.90
Total Expenses
194.24
-32.95%
289.72
+2.59%
282.41
+52.27%
185.46
Operating Income
-184.56
-19.41%
-154.56
+19.09%
-191.04
-45.21%
-131.56
Total Operating Income As Reported
-214.64
-38.87%
-154.56
+19.09%
-191.04
-45.21%
-131.56
EBITDA
-183.66
-19.52%
-153.67
+19.17%
-190.11
-45.33%
-130.81
Normalized EBITDA
-153.26
+0.15%
-153.48
+19.07%
-189.65
-45.42%
-130.42
Reconciled Depreciation
0.90
+0.22%
0.89
-3.77%
0.93
+24.73%
0.74
EBIT
-184.56
-19.41%
-154.56
+19.09%
-191.04
-45.21%
-131.56
Total Unusual Items
-30.41
-16336.76%
-0.18
+59.61%
-0.46
-15.37%
-0.40
Total Unusual Items Excluding Goodwill
-30.41
-16336.76%
-0.18
+59.61%
-0.46
-15.37%
-0.40
Special Income Charges
-30.08
0.00
0.00
—
Restructuring And Mergern Acquisition
30.08
0.00
0.00
—
Net Income
-244.09
-99.57%
-122.31
+16.81%
-147.03
-25.72%
-116.95
Pretax Income
-200.83
-55.77%
-128.93
+19.66%
-160.48
-27.77%
-125.61
Net Non Operating Interest Income Expense
14.14
-45.23%
25.82
-16.76%
31.01
+388.49%
6.35
Net Interest Income
14.14
-45.23%
25.82
-16.76%
31.01
+388.49%
6.35
Interest Income Non Operating
14.14
-45.23%
25.82
-16.76%
31.01
+388.49%
6.35
Interest Income
14.14
-45.23%
25.82
-16.76%
31.01
+388.49%
6.35
Other Income Expense
-30.41
-16336.76%
-0.18
+59.61%
-0.46
-15.37%
-0.40
Other Non Operating Income Expenses
—
—
-0.46
-15.37%
-0.40
Gain On Sale Of Security
-0.33
-77.30%
-0.18
+59.61%
-0.46
-15.37%
-0.40
Tax Provision
43.26
+753.52%
-6.62
+50.79%
-13.45
-55.41%
-8.66
Tax Rate For Calcs
0.00
+143.45%
0.00
-38.75%
0.00
+21.64%
0.00
Tax Effect Of Unusual Items
-3.80
-39914.94%
-0.01
+75.26%
-0.04
-40.32%
-0.03
Net Income Including Noncontrolling Interests
-244.09
-99.57%
-122.31
+16.81%
-147.03
-25.72%
-116.95
Net Income From Continuing Operation Net Minority Interest
-244.09
-99.57%
-122.31
+16.81%
-147.03
-25.72%
-116.95
Net Income From Continuing And Discontinued Operation
-244.09
-99.57%
-122.31
+16.81%
-147.03
-25.72%
-116.95
Net Income Continuous Operations
-244.09
-99.57%
-122.31
+16.81%
-147.03
-25.72%
-116.95
Normalized Income
-217.49
-78.07%
-122.13
+16.69%
-146.61
-25.76%
-116.58
Net Income Common Stockholders
-244.09
-99.57%
-122.31
+16.81%
-147.03
-25.72%
-116.95
Diluted EPS
-4.53
-99.56%
-2.27
+17.75%
-2.76
-11.74%
-2.47
Basic EPS
-4.53
-99.56%
-2.27
+17.75%
-2.76
-11.74%
-2.47
Basic Average Shares
53.83
+0.11%
53.77
+1.04%
53.22
+12.34%
47.37
Diluted Average Shares
53.83
+0.11%
53.77
+1.04%
53.22
+12.34%
47.37
Diluted NI Availto Com Stockholders
-244.09
-99.57%
-122.31
+16.81%
-147.03
-25.72%
-116.95
Line Item Trend 2023-12-31
Total Assets
696.38
Current Assets
639.28
Cash Cash Equivalents And Short Term Investments
618.83
Cash And Cash Equivalents
618.83
Receivables
5.16
Accounts Receivable
5.16
Other Receivables
—
Prepaid Assets
11.80
Restricted Cash
1.35
Other Current Assets
2.14
Total Non Current Assets
57.10
Net PPE
16.00
Gross PPE
23.41
Accumulated Depreciation
-7.42
Properties
0.00
Machinery Furniture Equipment
11.25
Other Properties
12.16
Leases
0.00
Non Current Deferred Assets
33.89
Non Current Deferred Taxes Assets
33.89
Other Non Current Assets
7.21
Total Liabilities Net Minority Interest
135.02
Current Liabilities
56.89
Payables And Accrued Expenses
53.36
Payables
25.39
Accounts Payable
25.39
Current Accrued Expenses
27.97
Total Tax Payable
—
Income Tax Payable
—
Current Debt And Capital Lease Obligation
1.11
Current Capital Lease Obligation
1.11
Current Deferred Liabilities
0.00
Current Deferred Revenue
0.00
Other Current Liabilities
2.42
Total Non Current Liabilities Net Minority Interest
78.13
Long Term Debt And Capital Lease Obligation
10.72
Long Term Capital Lease Obligation
10.72
Non Current Deferred Liabilities
67.41
Non Current Deferred Revenue
67.41
Other Non Current Liabilities
—
Stockholders Equity
561.37
Common Stock Equity
561.37
Capital Stock
0.54
Common Stock
0.54
Share Issued
53.68
Ordinary Shares Number
53.68
Treasury Shares Number
0.00
Additional Paid In Capital
1,540.86
Retained Earnings
-980.03
Total Equity Gross Minority Interest
561.37
Total Capitalization
561.37
Working Capital
582.39
Invested Capital
561.37
Total Debt
11.84
Capital Lease Obligations
11.84
Net Tangible Assets
561.37
Tangible Book Value
561.37
Line Item Trend 2025-12-31 2024-12-31 2023-12-31 2022-12-31
Operating Cash Flow
-163.58
-9.02%
-150.05
-12.06%
-133.91
-23.05%
-108.82
Cash Flow From Continuing Operating Activities
-163.58
-9.02%
-150.05
-12.06%
-133.91
-23.05%
-108.82
Net Income From Continuing Operations
-244.09
-99.57%
-122.31
+16.81%
-147.03
-25.72%
-116.95
Depreciation Amortization Depletion
0.90
+0.22%
0.89
-3.77%
0.93
+24.73%
0.74
Depreciation
—
—
—
—
Depreciation And Amortization
0.90
+0.22%
0.89
-3.77%
0.93
+24.73%
0.74
Other Non Cash Items
2.81
+4.27%
2.69
-64.03%
7.48
+24.80%
6.00
Stock Based Compensation
37.64
-18.11%
45.96
+12.34%
40.91
+30.62%
31.32
Deferred Tax
43.24
+562.65%
-9.35
+40.43%
-15.69
-40.92%
-11.13
Deferred Income Tax
43.24
+562.65%
-9.35
+40.43%
-15.69
-40.92%
-11.13
Operating Gains Losses
0.10
—
0.01
+1400.00%
0.00
Gain Loss On Sale Of PPE
0.10
0.00
-100.00%
0.01
+1400.00%
0.00
Change In Working Capital
-4.17
+93.86%
-67.94
-230.94%
-20.53
-9.18%
-18.80
Change In Receivables
0.00
-100.00%
5.16
+200.00%
-5.16
0.00
Changes In Account Receivables
0.00
-100.00%
5.16
+200.00%
-5.16
0.00
Change In Prepaid Assets
10.63
+318.59%
2.54
+200.08%
-2.54
+76.53%
-10.81
Change In Payables And Accrued Expense
-15.78
+13.78%
-18.30
-180.06%
22.86
+92.63%
11.87
Change In Payable
-15.78
+13.78%
-18.30
-180.06%
22.86
+92.63%
11.87
Change In Account Payable
-15.78
+13.78%
-18.30
-180.06%
22.86
+92.63%
11.87
Change In Other Working Capital
-9.63
+82.52%
-55.11
-87.89%
-29.33
-111.69%
-13.86
Change In Other Current Liabilities
10.61
+574.46%
-2.24
+64.84%
-6.36
-5.91%
-6.00
Investing Cash Flow
-0.14
+53.69%
-0.30
+89.25%
-2.77
-497.63%
-0.46
Cash Flow From Continuing Investing Activities
-0.14
+53.69%
-0.30
+89.25%
-2.77
-497.63%
-0.46
Net PPE Purchase And Sale
-0.14
+53.69%
-0.30
+89.25%
-2.77
-497.63%
-0.46
Purchase Of PPE
-0.14
+53.69%
-0.30
+89.40%
-2.81
-505.60%
-0.46
Sale Of PPE
0.00
0.00
-100.00%
0.04
0.00
Capital Expenditure
-0.14
+53.69%
-0.30
+89.40%
-2.81
-505.60%
-0.46
Financing Cash Flow
-0.14
-108.94%
1.55
-96.55%
45.10
-81.32%
241.46
Cash Flow From Continuing Financing Activities
-0.14
-108.94%
1.55
-96.55%
45.10
-81.32%
241.46
Net Common Stock Issuance
-0.14
+60.62%
-0.35
-101.50%
23.58
-89.45%
223.62
Common Stock Payments
-0.14
+60.62%
-0.35
—
—
Repurchase Of Capital Stock
-0.14
+60.62%
-0.35
—
—
Proceeds From Stock Option Exercised
0.00
-100.00%
1.91
-91.14%
21.52
+20.62%
17.84
Changes In Cash
-163.86
-10.12%
-148.79
-62.48%
-91.58
-169.29%
132.17
Beginning Cash Position
472.25
-23.96%
621.04
-12.85%
712.62
+22.77%
580.45
End Cash Position
308.39
-34.70%
472.25
-23.96%
621.04
-12.85%
712.62
Free Cash Flow
-163.72
-8.89%
-150.35
-9.97%
-136.72
-25.10%
-109.28
Income Tax Paid Supplemental Data
0.93
-70.65%
3.17
+104.12%
1.55
-41.56%
2.66
Common Stock Issuance
0.00
0.00
-100.00%
23.58
-89.45%
223.62
Issuance Of Capital Stock
0.00
0.00
-100.00%
23.58
-89.45%
223.62
SEC Filings

Recent 10-K, 10-Q, 8-K, and Form 4 (insider) filings.

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