1y return+89.7%S&P 500 +20.9%
3y return−11.6%S&P 500 +68.5%
5y return−31.3%S&P 500 +74.5%
10y return+108.0%S&P 500 +256.5%
These returns are for its stock picks as disclosed on Form 13F: last quarter's holdings, valued at this quarter's prices. They miss trades within each quarter, short positions, options, bonds, cash and fees, so they aren't the returns its clients got.
$100 invested in its stock picks
Since June 30, 2016: $208 against $357 in the S&P 500.2
EcoR1 Capital, LLCS&P 500 (SPY)
Top holdings
At the end of June 30, 2026. Change is in shares since the quarter before.2
| Stock | Value | Share of portfolio | Change |
|---|---|---|---|
| ZYMEZymeworks Inc | $600.4M | 29.8% | |
| ANABAnaptysbio Inc | $531.9M | 26.4% | |
| AKTSAktis Oncology Inc | $155.5M | 7.7% | |
| CGONCg Oncology Inc | $106.2M | 5.3% | +35.6% |
| ETONEton Pharmaceuticals Inc | $78.6M | 3.9% | |
| Crispr Therapeutics AgCUSIP H17182108 | $75.8M | 3.8% | |
| ORICOric Pharmaceuticals Inc | $72.9M | 3.6% | |
| TRAXFirst Tracks Biotherapeutics | $63.9M | 3.2% | New |
| LKFTLakefront Biotherapeutics Nv | $50.0M | 2.5% | |
| NGNENeurogene Inc | $40.0M | 2.0% | |
| STOKStoke Therapeutics Inc | $24.0M | 1.2% | +635.0% |
| FULCFulcrum Therapeutics Inc | $24.0M | 1.2% | New |
| LEGNLegend Biotech Corp | $23.1M | 1.1% | New |
| BBOTBridgebio Oncology Therapeut | $21.5M | 1.1% | |
| MBXMbx Biosciences Inc | $21.4M | 1.1% | −50.0% |
| ZBIOZenas Biopharma Inc | $20.0M | 1.0% | |
| ATRAAtara Biotherapeutics Inc | $17.8M | 0.9% | +1458.3% |
| RLAYRelay Therapeutics Inc | $13.1M | 0.6% | −63.4% |
| AURAAura Biosciences Inc | $11.8M | 0.6% | New |
| ODTXOdyssey Therapeutics Inc | $10.4M | 0.5% | New |
| EIKNEikon Therapeutics Inc | $9.6M | 0.5% | |
| Pharvaris N VCUSIP N69605108 | $8.1M | 0.4% | New |
| Zura Bio LtdCUSIP G9TY5A101 | $7.0M | 0.3% | |
| PHATPhathom Pharmaceuticals Inc | $6.8M | 0.3% | |
| NRIXNurix Therapeutics Inc | $6.6M | 0.3% | New |
Best picks still held
How each current holding has done since the quarter it first appeared in its filings (up to six years back).
| Stock | Held since | Return since | Now worth |
|---|---|---|---|
| ETONEton Pharmaceuticals Inc | September 30, 2024 | +503.3% | $78.6M |
| ZYMEZymeworks Inc | December 31, 2022 | +232.6% | $600.4M |
| ANABAnaptysbio Inc | June 30, 2020 | +202.1% | $531.9M |
| MBXMbx Biosciences Inc | September 30, 2024 | +112.5% | $21.4M |
| RLAYRelay Therapeutics Inc | March 31, 2026 | +88.0% | $13.1M |
| AKTSAktis Oncology Inc | March 31, 2026 | +80.2% | $155.5M |
| CGONCg Oncology Inc | December 31, 2025 | +71.1% | $106.2M |
| NGNENeurogene Inc | December 31, 2023 | +62.3% | $40.0M |
| EIKNEikon Therapeutics Inc | March 31, 2026 | +23.3% | $9.6M |
| ERASErasca Inc | March 31, 2026 | +13.2% | $6.0M |
Sold off last quarter
- Jazz Pharmaceuticals PLCCUSIP G50871105 was $322.6M
- Centessa Pharmaceuticals PLCCUSIP 152309100 was $238.3M
- Crinetics Pharmaceuticals InCUSIP 22663K107 was $155.7M
- XNCRXencor Inc was $26.3M
- REPLReplimune Group Inc was $7.7M
- PRLDPrelude Therapeutics Inc was $3.2M
- IBIOIbio Inc was $3.0M
Quarter by quarter
| Quarter | Its picks | S&P 500 |
|---|---|---|
| June 30, 2026 | +18.0% | +14.8% |
| March 31, 2026 | +2.8% | −4.6% |
| December 31, 2025 | +19.0% | +2.4% |
| September 30, 2025 | +31.4% | +7.8% |
| June 30, 2025 | −4.5% | +10.5% |
| March 31, 2025 | −27.6% | −4.6% |
| December 31, 2024 | −13.5% | +2.1% |
| September 30, 2024 | −2.1% | +5.4% |
| June 30, 2024 | −17.6% | +4.0% |
| March 31, 2024 | +1.9% | +10.0% |
| December 31, 2023 | +23.5% | +11.2% |
| September 30, 2023 | −23.4% | −3.6% |
| June 30, 2023 | +13.0% | +8.3% |
| March 31, 2023 | −4.8% | +7.0% |
| December 31, 2022 | −3.9% | +7.1% |
| September 30, 2022 | +21.3% | −5.3% |
| June 30, 2022 | −19.5% | −16.5% |
| March 31, 2022 | −21.1% | −4.9% |
| December 31, 2021 | −9.3% | +10.7% |
| September 30, 2021 | +7.6% | +0.3% |
Sources
Every number on this page points here. Each one links to the public record.
- 1SEC EDGAR: EcoR1 Capital, LLC Form 13F filingshttps://www.sec.gov/cgi-bin/browse-edgar?action=getcompany&CIK=1587114&type=13F-HR&dateb=&owner=include&count=40CIK 1587114
- 2SEC: 13F for the quarter ended June 30, 2026https://www.sec.gov/Archives/edgar/data/1587114/000093583626000415/Filed August 14, 2026 · accession 0000935836-26-000415