EcoR1 Capital, LLC 13F holdings, Q1 2026
Holdings as of March 31, 2026 · filings on SEC EDGAR · latest filing →
EcoR1 Capital, LLC disclosed 29 US equity positions worth $2.3bn in its Q1 2026 13F filing. The largest position was ZYME at 24.6% of the reported book, followed by ANAB and JAZZ.
What did EcoR1 Capital, LLC own in Q1 2026? Top 29 positions
| # | Stock | Sector | Weight | Value | Shares | Δ shares | vs prior |
|---|---|---|---|---|---|---|---|
| 1 | ZYME ZYMEWORKS INC | Healthcare | 24.6% | $575.2m | 22,970,388 | – | |
| 2 | ANAB ANAPTYSBIO INC | Healthcare | 18.7% | $437.0m | 7,880,094 | – | |
| 3 | JAZZ JAZZ PHARMACEUTICALS PLC | Healthcare | 13.8% | $322.6m | 1,706,469 | – | |
| 4 | CNTA CENTESSA PHARMACEUTICALS PLC | 10.2% | $238.3m | 6,000,000 | – | ||
| 5 | CRNXGBP CRINETICS PHARMACEUTICALS IN | 6.7% | $155.7m | 4,288,120 | – | ||
| 6 | AKTS AKTIS ONCOLOGY INC | 3.7% | $86.3m | 4,824,469 | – | ||
| 7 | ORIC ORIC PHARMACEUTICALS INC | Healthcare | 3.6% | $85.2m | 6,728,116 | – | |
| 8 | CGON CG ONCOLOGY INC | Healthcare | 3.2% | $74.6m | 1,102,000 | – | |
| 9 | CRSP CRISPR THERAPEUTICS AG | Healthcare | 2.8% | $66.1m | 1,389,276 | – | |
| 10 | ETON ETON PHARMACEUTICALS INC | 2.3% | $53.6m | 2,171,938 | – | ||
| 11 | LKFT GALAPAGOS NV | Healthcare | 2.1% | $50.0m | 1,667,119 | – | |
| 12 | XNCR XENCOR INC | Healthcare | 1.1% | $26.3m | 2,183,000 | – | |
| 13 | NGNE NEUROGENE INC | 1.1% | $25.6m | 1,271,342 | – | ||
| 14 | BBOT BRIDGEBIO ONCOLOGY THERAPEUT | 1.1% | $25.3m | 2,823,126 | – | ||
| 15 | MBX MBX BIOSCIENCES INC | Healthcare | 1.0% | $23.2m | 777,000 | – | |
| 16 | RLAY RELAY THERAPEUTICS INC | Healthcare | 0.8% | $19.0m | 1,904,762 | – | |
| 17 | ZBIO ZENAS BIOPHARMA INC | 0.7% | $15.4m | 789,500 | – | ||
| 18 | ERAS ERASCA INC | Healthcare | 0.6% | $14.6m | 900,000 | – | |
| 19 | EIKN EIKON THERAPEUTICS INC | 0.3% | $7.8m | 732,606 | – | ||
| 20 | REPL REPLIMUNE GROUP INC | Healthcare | 0.3% | $7.7m | 1,000,000 | – | |
| 21 | ZURA ZURA BIO LTD | Healthcare | 0.3% | $7.0m | 1,179,715 | – | |
| 22 | PHAT PHATHOM PHARMACEUTICALS INC | Healthcare | 0.3% | $6.9m | 625,000 | – | |
| 23 | MREO MEREO BIOPHARMA GROUP PLC | Healthcare | 0.2% | $4.4m | 13,368,855 | – | |
| 24 | STOK STOKE THERAPEUTICS INC | Healthcare | 0.1% | $3.3m | 100,000 | – | |
| 25 | PRLD PRELUDE THERAPEUTICS INC | 0.1% | $3.2m | 947,049 | – | ||
| 26 | IBIO IBIO INC | 0.1% | $3.0m | 1,583,000 | – | ||
| 27 | HELIX ACQUISITION CORP III USD | 0.1% | $2.0m | 200,000 | – | ||
| 28 | ATRA ATARA BIOTHERAPEUTICS INC | 0.0% | $471.1k | 99,593 | – | ||
| 29 | SURROZEN INC | 0.0% | $129.5k | 4,444 | – |
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.