Q1 2026 · 13F-HR
EcoR1 Capital, LLCholdings as filed
Filed 2026-05-15 · accession 0000935836-26-000270
$2.36B
Reported value
30
Positions
2026-03-31
Period end
The Brief · EcoR1 Capital, LLC · Q1 2026
AI · grounded in 13F
EcoR1 Capital, LLC closed its position in IMNM for a reduction of $61.3M. The fund established a new position in AKTS worth $86.3M and increased its stake in CNTA by 105.8%. Other notable activity includes new positions in RLAY and ERAS, alongside the closure of positions in GPCR and PCVX.
Holdings as filed
| CUSIP | Ticker | Issuer | Value | % port. | Shares | Class | Voting |
|---|---|---|---|---|---|---|---|
| 98985Y108 | ZYME | ZYMEWORKS INC | $575.2M | 24.4% | 22,970,388 | Common | SOLE |
| 032724106 | ANAB | ANAPTYSBIO INC | $437.0M | 18.5% | 7,880,094 | Common | SOLE |
| G50871105 | JAZZ | JAZZ PHARMACEUTICALS PLC | $322.6M | 13.7% | 1,706,469 | Common | SOLE |
| 152309100 | CNTA | CENTESSA PHARMACEUTICALS PLC | $238.3M | 10.1% | 6,000,000 | Common | SOLE |
| 22663K107 | CRNX | CRINETICS PHARMACEUTICALS IN | $155.7M | 6.61% | 4,288,120 | Common | SOLE |
| 01021M104 | AKTS | AKTIS ONCOLOGY INC | $86.3M | 3.66% | 4,824,469 | Common | SOLE |
| 68622P109 | ORIC | ORIC PHARMACEUTICALS INC | $85.2M | 3.62% | 6,728,116 | Common | SOLE |
| 156944100 | CGON | CG ONCOLOGY INC | $74.6M | 3.17% | 1,102,000 | Common | SOLE |
| H17182108 | CRSP | CRISPR THERAPEUTICS AG | $66.1M | 2.80% | 1,389,276 | Common | SOLE |
| 29772L108 | ETON | ETON PHARMACEUTICALS INC | $53.6M | 2.27% | 2,171,938 | Common | SOLE |
| 36315X101 | LKFT | GALAPAGOS NV | $50.0M | 2.12% | 1,667,119 | Common | SOLE |
| 98401F105 | XNCR | XENCOR INC | $26.3M | 1.12% | 2,183,000 | Common | SOLE |
| 64135M105 | NGNE | NEUROGENE INC | $25.6M | 1.09% | 1,271,342 | Common | SOLE |
| 107924102 | BBOT | BRIDGEBIO ONCOLOGY THERAPEUT | $25.3M | 1.07% | 2,823,126 | Common | SOLE |
| 55287L101 | MBX | MBX BIOSCIENCES INC | $23.2M | 0.98% | 777,000 | Common | SOLE |
| 75943R102 | RLAY | RELAY THERAPEUTICS INC | $19.0M | 0.80% | 1,904,762 | Common | SOLE |
| 152309100 | CNTA | CENTESSA PHARMACEUTICALS PLC | $16.3M | 0.69% | 410,800 | CALL | SOLE |
| 98937L105 | ZBIO | ZENAS BIOPHARMA INC | $15.4M | 0.66% | 789,500 | Common | SOLE |
| 29479A108 | ERAS | ERASCA INC | $14.6M | 0.62% | 900,000 | Common | SOLE |
| 282564103 | EIKN | EIKON THERAPEUTICS INC | $7.8M | 0.33% | 732,606 | Common | SOLE |
| 76029N106 | REPL | REPLIMUNE GROUP INC | $7.7M | 0.32% | 1,000,000 | Common | SOLE |
| G9TY5A101 | ZURA | ZURA BIO LTD | $7.0M | 0.30% | 1,179,715 | Common | SOLE |
| 71722W107 | PHAT | PHATHOM PHARMACEUTICALS INC | $6.9M | 0.29% | 625,000 | Common | SOLE |
| 589492107 | MREO | MEREO BIOPHARMA GROUP PLC | $4.4M | 0.19% | 13,368,855 | Common | SOLE |
| 86150R107 | STOK | STOKE THERAPEUTICS INC | $3.3M | 0.14% | 100,000 | Common | SOLE |
| 74065P101 | PRLD | PRELUDE THERAPEUTICS INC | $3.2M | 0.14% | 947,049 | Common | SOLE |
| 451033708 | IBIO | IBIO INC | $3.0M | 0.13% | 1,583,000 | Common | SOLE |
| G4444S107 | HLXC | HELIX ACQUISITION CORP III USD | $2.0M | 0.09% | 200,000 | Common | SOLE |
| 046513206 | ATRA | ATARA BIOTHERAPEUTICS INC | $471,075 | 0.02% | 99,593 | Common | SOLE |
| 86889P117 | SRZNW | SURROZEN INC | $129,454 | 0.01% | 4,444 | Common | SOLE |
Source: SEC EDGAR · raw 13F holdings as filed. The Class column shows the option type when reported (Put/Call) or Common when the issuer's equity is held directly. 13F discloses long positions only.