PRTA
Prothena Corporation plc NASDAQ Listed Dec 18, 2012$8.58
+1.06%
vs $8.49
Mkt Cap $461.9M
52w Low $7.54
26.2% of range
52w High $11.51
50d MA $8.96
200d MA $9.60
P/E (TTM)
-3.0x
EV/EBITDA
—
P/B
1.6x
Debt/Equity
0.1x
ROE
-87.0%
P/FCF
-2.8x
RSI (14)
47.80
ATR (14)
$0.37
Beta
-0.33
50d MA
$8.96
200d MA
$9.60
Avg Volume
587.8K
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 Aß-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.
77 Sir John Rogerson’s Quay · Dublin, L2 2 · IE
| Date | Time | Est | Rptd | Surp | Base | Gap% | D1% | D2% | D3% | D4% | D5% | Guide ▲★ |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Aug 6, 2026 | AMC | -0.39 | -0.32 | +17.9% | — | — | — | — | — | — | — | — |
| May 7, 2026 | AMC | -0.31 | 0.60 | +293.5% | 10.52 | +4.6% | +2.0% | -9.9% | -2.5% | +1.8% | +2.7% | — |
| Feb 19, 2026 | AMC | -0.45 | -0.44 | +2.2% | 9.03 | +3.9% | -0.1% | +0.6% | -1.1% | -1.0% | -2.7% | — |
| Nov 6, 2025 | AMC | -0.60 | -0.67 | -11.7% | 10.08 | +4.1% | +4.8% | -0.3% | -0.5% | +3.5% | -6.2% | — |
| Aug 4, 2025 | AMC | -1.11 | -1.86 | -67.6% | 6.94 | +1.3% | +1.3% | +12.7% | -2.5% | -0.4% | -0.3% | — |
| May 8, 2025 | AMC | -0.92 | -1.12 | -21.7% | 7.10 | -1.1% | +4.6% | +2.4% | -0.3% | -9.2% | -2.5% | — |
| Feb 20, 2025 | AMC | -1.02 | -1.08 | -5.9% | 15.25 | +4.3% | +2.0% | -2.1% | -3.9% | -0.5% | +4.0% | — |
| Nov 12, 2024 | AMC | -1.18 | -1.10 | +6.8% | 17.36 | +0.0% | -0.7% | -6.6% | -13.0% | -3.6% | +4.0% | — |
| Aug 8, 2024 | AMC | -1.05 | 1.22 | +216.2% | 19.68 | +10.0% | +4.4% | -2.1% | -0.7% | -1.1% | +5.6% | — |
| May 8, 2024 | AMC | -1.21 | -1.34 | -10.7% | 23.03 | -3.0% | -4.5% | -3.0% | -3.0% | -0.1% | +8.3% | — |
| Feb 15, 2024 | AMC | -1.23 | -1.26 | -2.4% | 28.52 | -0.2% | -1.8% | -1.7% | -1.7% | -0.4% | +1.0% | — |
| Nov 2, 2023 | AMC | -0.32 | 0.38 | +218.8% | 34.96 | +10.0% | +7.4% | -4.8% | +1.9% | -3.0% | -7.2% | — |
| Aug 3, 2023 | AMC | -0.92 | -1.03 | -12.0% | 66.53 | +5.4% | -7.3% | +1.7% | -2.9% | +0.9% | +1.5% | — |
| May 4, 2023 | AMC | -0.83 | -0.89 | -7.2% | 70.16 | -0.4% | +12.0% | -2.2% | -1.5% | -0.8% | -2.2% | — |
| Date | Firm | Action | Grade | Target | Base | Open | Gap% | D1% | D2% | D3% | D4% | D5% |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Feb 20 | RBC Capital | Maintains | Sector Perform → Sector Perform | — | $9.03 | $9.38 | +3.9% | -0.1% | +0.6% | -1.1% | -1.0% | -2.7% |
| Dec 1 | Citizens | Maintains | Market Outperform → Market Outperform | — | $10.75 | $10.98 | +2.1% | -4.5% | +0.8% | +7.9% | -0.1% | -0.8% |
| Nov 7 | RBC Capital | Maintains | Sector Perform → Sector Perform | — | $10.08 | $10.49 | +4.1% | +4.8% | -0.3% | -0.5% | +3.5% | -6.2% |
| Nov 7 | HC Wainwright & Co. | Maintains | Buy → Buy | — | $10.08 | $10.49 | +4.1% | +4.8% | -0.3% | -0.5% | +3.5% | -6.2% |
| Oct 28 | Piper Sandler | Maintains | Overweight → Overweight | — | $10.37 | $11.14 | +7.4% | +1.6% | +1.0% | -1.6% | +2.6% | -2.0% |
| Oct 7 | HC Wainwright & Co. | Maintains | Buy → Buy | — | $9.86 | $10.12 | +2.6% | +3.1% | +1.8% | -0.5% | -2.4% | +3.0% |
| Sep 2 | JMP Securities | Maintains | Market Outperform → Market Outperform | — | $8.20 | $8.17 | -0.4% | +0.9% | +1.5% | -2.1% | +4.1% | -0.7% |
| Aug 28 | Piper Sandler | Maintains | Overweight → Overweight | — | $8.56 | $8.22 | -4.0% | -3.7% | -0.5% | +0.9% | +1.5% | -2.1% |
| Aug 28 | Chardan Capital | Maintains | Buy → Buy | — | $8.56 | $8.22 | -4.0% | -3.7% | -0.5% | +0.9% | +1.5% | -2.1% |
| Aug 5 | HC Wainwright & Co. | Maintains | Buy → Buy | — | $6.94 | $7.03 | +1.3% | +1.3% | +12.7% | -2.5% | -0.4% | -0.3% |
| Aug 5 | RBC Capital | Maintains | Sector Perform → Sector Perform | — | $6.94 | $7.03 | +1.3% | +1.3% | +12.7% | -2.5% | -0.4% | -0.3% |
| Aug 5 | Chardan Capital | Maintains | Buy → Buy | — | $6.94 | $7.03 | +1.3% | +1.3% | +12.7% | -2.5% | -0.4% | -0.3% |
| Jun 20 | Cantor Fitzgerald | Maintains | Neutral → Neutral | — | $5.75 | $5.92 | +3.0% | -0.5% | +5.9% | +0.2% | -1.3% | +3.2% |
| May 28 | BofA Securities | Downgrade | Neutral → Underperform | — | $4.58 | $4.48 | -2.2% | +0.4% | +2.2% | -2.3% | +1.5% | +3.6% |
| May 27 | Piper Sandler | Maintains | Overweight → Overweight | — | $6.58 | $4.79 | -27.2% | -30.4% | +0.4% | +2.2% | -2.3% | +1.5% |
| May 27 | Oppenheimer | Downgrade | Outperform → Perform | — | $6.58 | $4.79 | -27.2% | -30.4% | +0.4% | +2.2% | -2.3% | +1.5% |
| May 27 | HC Wainwright & Co. | Maintains | Buy → Buy | — | $6.58 | $4.79 | -27.2% | -30.4% | +0.4% | +2.2% | -2.3% | +1.5% |
| May 27 | JMP Securities | Maintains | Market Outperform → Market Outperform | — | $6.58 | $4.79 | -27.2% | -30.4% | +0.4% | +2.2% | -2.3% | +1.5% |
| May 27 | Chardan Capital | Maintains | Buy → Buy | — | $6.58 | $4.79 | -27.2% | -30.4% | +0.4% | +2.2% | -2.3% | +1.5% |
| May 9 | HC Wainwright & Co. | Maintains | Buy → Buy | — | $7.10 | $7.02 | -1.1% | +4.6% | +2.4% | -0.3% | -9.2% | -2.5% |
| May 9 | JMP Securities | Maintains | Market Outperform → Market Outperform | — | $7.10 | $7.02 | -1.1% | +4.6% | +2.4% | -0.3% | -9.2% | -2.5% |
| May 9 | Chardan Capital | Maintains | Buy → Buy | — | $7.10 | $7.02 | -1.1% | +4.6% | +2.4% | -0.3% | -9.2% | -2.5% |
| Feb 26 | Piper Sandler | Maintains | Overweight → Overweight | — | $14.63 | $15.08 | +3.1% | -0.5% | +4.0% | +4.5% | -9.4% | +5.1% |
| Feb 24 | HC Wainwright & Co. | Maintains | Buy → Buy | — | $15.56 | $15.57 | +0.1% | -2.1% | -3.9% | -0.5% | +4.0% | +4.5% |
| Feb 21 | Cantor Fitzgerald | Maintains | Overweight → Overweight | — | $15.25 | $15.91 | +4.3% | +2.0% | -2.1% | -3.9% | -0.5% | +4.0% |
| Feb 21 | HC Wainwright & Co. | Maintains | Buy → Buy | — | $15.25 | $15.91 | +4.3% | +2.0% | -2.1% | -3.9% | -0.5% | +4.0% |
| Feb 21 | Citizens Capital Markets | Maintains | Market Outperform → Market Outperform | — | $15.25 | $15.91 | +4.3% | +2.0% | -2.1% | -3.9% | -0.5% | +4.0% |
| Feb 21 | Chardan Capital | Maintains | Buy → Buy | — | $15.25 | $15.91 | +4.3% | +2.0% | -2.1% | -3.9% | -0.5% | +4.0% |
| Feb 21 | RBC Capital | Maintains | Sector Perform → Sector Perform | — | $15.25 | $15.91 | +4.3% | +2.0% | -2.1% | -3.9% | -0.5% | +4.0% |
| Feb 7 | Oppenheimer | Maintains | Outperform → Outperform | — | $14.44 | $14.55 | +0.8% | -2.7% | +0.1% | -2.0% | +0.2% | +0.5% |
| Dec 20 | HC Wainwright & Co. | Maintains | Buy → Buy | — | $16.01 | $15.89 | -0.7% | -4.9% | +0.7% | +0.5% | +2.2% | -3.8% |
| Dec 19 | BofA Securities | Maintains | Neutral → Neutral | — | $11.95 | $13.75 | +15.1% | +34.0% | -4.9% | +0.7% | +0.5% | +2.2% |
| Nov 13 | HC Wainwright & Co. | Maintains | Buy → Buy | — | $17.36 | $17.36 | +0.0% | -0.7% | -6.6% | -13.0% | -3.6% | +4.0% |
| Oct 1 | HC Wainwright & Co. | Maintains | Buy → Buy | — | $16.73 | $16.73 | +0.0% | -0.5% | +0.2% | +0.7% | +0.4% | -1.6% |
| Oct 1 | BofA Securities | Maintains | Neutral → Neutral | — | $16.73 | $16.73 | +0.0% | -0.5% | +0.2% | +0.7% | +0.4% | -1.6% |
| Aug 14 | Oppenheimer | Maintains | Outperform → Outperform | — | $19.98 | $20.06 | +0.4% | -1.1% | +5.6% | -0.5% | +2.0% | -1.0% |
| Aug 9 | RBC Capital | Maintains | Sector Perform → Sector Perform | — | $19.68 | $21.65 | +10.0% | +4.4% | -2.1% | -0.7% | -1.1% | +5.6% |
| Jun 26 | RBC Capital | Maintains | Sector Perform → Sector Perform | — | $20.77 | $20.61 | -0.8% | -3.9% | +2.9% | +0.5% | -0.8% | -0.4% |
| May 9 | JMP Securities | Maintains | Market Outperform → Market Outperform | — | $23.03 | $22.35 | -3.0% | -4.5% | -3.0% | -3.0% | -0.1% | +8.3% |
| May 9 | HC Wainwright & Co. | Maintains | Buy → Buy | — | $23.03 | $22.35 | -3.0% | -4.5% | -3.0% | -3.0% | -0.1% | +8.3% |
| Mar 13 | HC Wainwright & Co. | Maintains | Buy → Buy | — | $27.54 | $27.63 | +0.3% | +3.8% | -7.4% | -1.5% | -3.8% | +0.0% |
| Feb 20 | Oppenheimer | Maintains | Outperform → Outperform | — | $28.02 | $27.41 | -2.2% | -1.7% | -1.7% | -0.4% | +1.0% | +3.5% |
| Feb 16 | JMP Securities | Maintains | Market Outperform → Market Outperform | — | $28.52 | $28.45 | -0.2% | -1.8% | -1.7% | -1.7% | -0.4% | +1.0% |
| Feb 16 | RBC Capital | Maintains | Sector Perform → Sector Perform | — | $28.52 | $28.45 | -0.2% | -1.8% | -1.7% | -1.7% | -0.4% | +1.0% |
| Jan 30 | BofA Securities | Downgrade | Buy → Neutral | — | $33.76 | $31.47 | -6.8% | -11.6% | -4.9% | -3.6% | -5.8% | -2.8% |
| Jan 25 | RBC Capital | Maintains | Sector Perform → Sector Perform | — | $32.93 | $33.06 | +0.4% | -2.6% | +1.8% | +3.5% | -11.6% | -4.9% |
| Jan 9 | Cantor Fitzgerald | Maintains | Overweight → Overweight | — | $35.28 | $34.08 | -3.4% | +12.3% | -9.5% | -3.0% | -0.4% | -4.5% |
| Dec 18 | Cantor Fitzgerald | Maintains | Overweight → Overweight | — | $39.99 | $40.00 | +0.0% | -8.3% | +2.0% | -1.3% | +0.9% | +5.4% |
| Nov 3 | JMP Securities | Maintains | Market Outperform → Market Outperform | — | $34.96 | $38.46 | +10.0% | +7.4% | -4.8% | +1.9% | -3.0% | -7.2% |
| Oct 23 | Cantor Fitzgerald | Maintains | Overweight → Overweight | — | $43.79 | $43.62 | -0.4% | -3.5% | -0.0% | -6.1% | -14.6% | +5.5% |
| Date | Insider | Title | Type | Shares | Price | Value | Owned After | D1% | D5% |
|---|---|---|---|---|---|---|---|---|---|
| Jun 16, 2026 | SCULLY WILLIAM P10% | — | Buy | 20,000 | $7.90 | $158K | 756,000 | +2.46% | +8.09% |
| Jun 2, 2026 | SCULLY WILLIAM P10% | — | Buy | 50,000 | $9.43 | $471K | 886,000 | +3.70% | -6.61% |
| May 22, 2026 | SCULLY WILLIAM P10% | — | Buy | 100,000 | $9.81 | $981K | 836,000 | -0.30% | -4.17% |
8-K · 7.01
! Medium
Prothena Corporation plc -- 8-K 7.01: Regulation FD Disclosure
Prothena Corporation authorized a $100 million share repurchase program, signaling management confidence in the stock valuation while potentially supporting future earnings per share.
Feb 27
8-K
Prothena Corporation plc -- 8-K Filing
Prothena's pipeline advanced with Roche initiating the Phase 3 PARAISO trial for prasinezumab in early Parkinson's disease and Novo Nordisk launching Phase 3 CLEOPATTRA for coramitug in ATTR cardiomyopathy, both targeting 2029 completion.
Feb 19
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All ↗
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|---|---|---|---|---|---|
| 1 | Fmr Llc | 7,551,218 | $73M | — | Mar 2026 |
| 2 | Morgan Stanley | 2,493,550 | $24M | Added | Dec 2025 |
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| 8 | Nuveen, Llc | 759,368 | $7M | — | Mar 2026 |
| 9 | Qube Research & Technologies Ltd | 614,603 | $6M | Added | Mar 2026 |
| 10 | Renaissance Technologies Llc | 607,515 | $6M | Added | Mar 2026 |
| 11 | Vanguard Capital Management Llc | 484,126 | $5M | New | Mar 2026 |
| 12 | Rangeley Capital, Llc | 449,460 | $4M | Reduced | Mar 2026 |
| 13 | Citadel Advisors Llc | 435,574 | $4M | Reduced | Mar 2026 |
| 14 | Bnp Paribas Financial Markets | 424,596 | $4M | — | Mar 2026 |
| 15 | Jane Street Group, Llc | 428,651 | $4M | Reduced | Dec 2025 |
| 16 | Point72 Asset Management | 399,830 | $4M | Reduced | Mar 2026 |
| 17 | Bank Of America Corp /de/ | 393,632 | $4M | Added | Mar 2026 |
| 18 | Man Group Plc | 381,574 | $4M | Added | Mar 2026 |
| 19 | Northern Trust Corp | 369,542 | $4M | Added | Mar 2026 |
| 20 | Ubs Group Ag | 328,491 | $3M | Reduced | Mar 2026 |
Mutual Funds / ETFs (N-PORT) — Top 20
All ↗
Valuation
Market Cap
$461.9M
Enterprise Value
$159.8M
P/E (TTM)
-3.04x
Forward P/E
34.78x
PEG Ratio
-0.02x
P/B
1.65x
P/S
7.97x
P/FCF
-2.82x
EV/EBITDA
—
Shares Out
53.8M
Financials (TTM)
Revenue
$57.9M
Net Income
-$151.2M
EBITDA
-$74.7M
Free Cash Flow
-$163.7M
Op Cash Flow
-$163.6M
EPS Basic
$-4.53
EPS Diluted
$-2.82
EPS Forward
$0.25
Gross Margin
46.9%
Op Margin
-217.9%
Net Margin
-260.9%
Balance Sheet
Total Assets
$326.8M
Total Liab.
$46.3M
Total Equity
$280.5M
Cash
$307.5M
LT Debt
$5.5M
Book Value/Sh
$5.21
Debt/Equity
0.05x
Current Ratio
7.72
Quick Ratio
7.72
Returns & Growth
ROE
-87.0%
ROA
-74.7%
ROIC
-63.9%
Rev Growth YoY
-92.8%
EPS Growth YoY
-99.6%
Price Returns
2W
+0.6%
1M
-10.6%
3M
-24.1%
6M
-4.7%
12M
+7.2%
Technicals
52W High
$11.51
52W Low
$7.54
50d MA
$8.96
200d MA
$9.60
RSI (14)
47.80
ATR (14)
$0.37
Beta
-0.33
Avg Volume
588K
Dividends
Div Rate
$0.00
Div Yield
—
Frequency
—
Ex-Div Date
—
Analyst Price Targets
Consensus
$19.00
High
$19.00
Low
$19.00
Median
$19.00
Data updated apr 26, 2026 8:52pm
· Source: financialmodelingprep.com