EcoR1 Capital, LLC 13F holdings, Q4 2025
Holdings as of December 31, 2025 · filings on SEC EDGAR · latest filing →
EcoR1 Capital, LLC disclosed 28 US equity positions worth $2.2bn in its Q4 2025 13F filing. The largest position was ZYME at 27.6% of the reported book, followed by ANAB and JAZZ. Against the Q3 2025 filing, it opened 9 new positions, added to 2 and reduced 3 among the top 28 holdings.
What did EcoR1 Capital, LLC own in Q4 2025? Top 28 positions
| # | Stock | Sector | Weight | Value | Shares | Δ shares | vs Q3 2025 |
|---|---|---|---|---|---|---|---|
| 1 | ZYME ZYMEWORKS INC | Healthcare | 27.6% | $604.8m | 22,970,388 | 0% | held |
| 2 | ANAB ANAPTYSBIO INC | Healthcare | 17.4% | $382.0m | 7,880,094 | 0% | held |
| 3 | JAZZ JAZZ PHARMACEUTICALS PLC | Healthcare | 13.2% | $290.1m | 1,706,469 | 0% | held |
| 4 | CRNXGBP CRINETICS PHARMACEUTICALS IN | 9.1% | $199.6m | 4,288,120 | 0% | held | |
| 5 | CNTA CENTESSA PHARMACEUTICALS PLC | 3.6% | $77.9m | 3,115,000 | 466% | added | |
| 6 | CRSP CRISPR THERAPEUTICS AG | Healthcare | 3.3% | $72.9m | 1,389,276 | 0% | held |
| 7 | MBX MBX BIOSCIENCES INC | Healthcare | 3.1% | $67.0m | 2,123,604 | 0% | held |
| 8 | IMNM IMMUNOME INC | Healthcare | 2.8% | $61.3m | 2,855,590 | -30% | reduced |
| 9 | ORIC ORIC PHARMACEUTICALS INC | Healthcare | 2.5% | $55.0m | 6,728,116 | 0% | held |
| 10 | LKFT GALAPAGOS NV | Healthcare | 2.5% | $54.5m | 1,667,119 | 0% | held |
| 11 | XNCR XENCOR INC | Healthcare | 2.3% | $49.8m | 3,251,112 | -47% | reduced |
| 12 | BBOT BRIDGEBIO ONCOLOGY THERAPEUT | 1.6% | $35.3m | 2,823,126 | 0% | held | |
| 13 | ETON ETON PHARMACEUTICALS INC | 1.6% | $34.3m | 2,030,544 | 0% | held | |
| 14 | CGON CG ONCOLOGY INC | Healthcare | 1.5% | $32.1m | 772,000 | – | new |
| 15 | ZBIO ZENAS BIOPHARMA INC | 1.3% | $28.7m | 789,500 | – | new | |
| 16 | NGNE NEUROGENE INC | 1.2% | $26.2m | 1,271,342 | 0% | held | |
| 17 | GPCR STRUCTURE THERAPEUTICS INC | Healthcare | 1.1% | $23.3m | 334,380 | – | new |
| 18 | PCVX VAXCYTE INC | Healthcare | 0.9% | $20.8m | 450,000 | – | new |
| 19 | AQST AQUESTIVE THERAPEUTICS INC | 0.8% | $17.0m | 2,625,000 | 0% | held | |
| 20 | VYGR VOYAGER THERAPEUTICS INC | Healthcare | 0.7% | $15.7m | 4,002,847 | 497% | added |
| 21 | ATRA ATARA BIOTHERAPEUTICS INC | 0.5% | $10.4m | 573,183 | 0% | held | |
| 22 | MNKD MANNKIND CORP | Healthcare | 0.4% | $9.4m | 1,660,000 | – | new |
| 23 | NUVATION BIO INC | 0.4% | $8.6m | 963,333 | 0% | held | |
| 24 | EOLS EVOLUS INC | Healthcare | 0.2% | $4.5m | 675,000 | – | new |
| 25 | IBIO IBIO INC | 0.2% | $4.3m | 2,228,000 | – | new | |
| 26 | MREO MEREO BIOPHARMA GROUP PLC | Healthcare | 0.1% | $3.3m | 7,856,466 | – | new |
| 27 | CAMP CAMP4 THERAPEUTICS CORP | 0.1% | $2.0m | 325,000 | – | new | |
| 28 | SURROZEN INC | 0.0% | $100.4k | 4,444 | -93% | reduced |
Weights are shares of the reported long US equity book (options excluded). Values are as filed, normalised to whole dollars. Share changes compare against the immediately preceding filing only.