Institutional
EcoR1 Capital, LLC
CIK 0001587114
$2.36B
Reported AUM
29
Positions
Q1 2026
Period
2026-05-15
Filed
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.
Portfolio · Q1 2026
Top holdings
| # | Stock | Issuer | Price | Day % | 1Y Gr. | 5Y Gr. | Value | % of book | Δ shares (QoQ) | Status |
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | ZYME | ZYMEWORKS INC | $21.93 | -3.44% | 80.67% | -31.16% | $575.2M | 24.41% | — | HELD |
| 2 | ANAB | ANAPTYSBIO INC | $53.17 | -3.39% | 223.06% | 211.45% | $437.0M | 18.55% | — | HELD |
| 3 | JAZZ | JAZZ PHARMACEUTICALS PLC | $253.04 | -2.07% | 119.30% | 92.34% | $322.6M | 13.69% | — | HELD |
| 4 | CNTA | CENTESSA PHARMACEUTICALS PLC | — | — | 0.00% | — | $254.6M | 10.81% | — | HELD |
| 5 | CRNX | CRINETICS PHARMACEUTICALS IN | $83.77 | 0.17% | 200.92% | 255.43% | $155.7M | 6.61% | — | HELD |
| 6 | AKTS | AKTIS ONCOLOGY INC | $22.37 | -2.74% | 2.68% | 14.26% | $86.3M | 3.66% | — | HELD |
| 7 | ORIC | ORIC PHARMACEUTICALS INC | $11.17 | -4.04% | 15.02% | -47.31% | $85.2M | 3.62% | — | HELD |
| 8 | CGON | CG ONCOLOGY INC | $70.29 | -3.75% | 168.87% | 58.22% | $74.6M | 3.17% | — | HELD |
| 9 | CRSP | CRISPR THERAPEUTICS AG | $48.03 | -0.85% | -13.64% | -61.23% | $66.1M | 2.80% | — | HELD |
| 10 | ETON | ETON PHARMACEUTICALS INC | $46.35 | -5.46% | 228.59% | 781.02% | $53.6M | 2.27% | — | HELD |
| 11 | LKFT | GALAPAGOS NV | $27.34 | -1.09% | -16.42% | -53.52% | $50.0M | 2.12% | — | HELD |
| 12 | XNCR | XENCOR INC | $20.11 | -6.42% | 169.30% | -36.55% | $26.3M | 1.12% | — | HELD |
| 13 | NGNE | NEUROGENE INC | $33.20 | -1.19% | 52.43% | -79.63% | $25.6M | 1.09% | — | HELD |
| 14 | BBOT | BRIDGEBIO ONCOLOGY THERAPEUT | $8.15 | -4.12% | -21.89% | -21.63% | $25.3M | 1.07% | — | HELD |
| 15 | MBX | MBX BIOSCIENCES INC | $65.46 | -1.50% | 381.16% | 188.91% | $23.2M | 0.98% | — | HELD |
| 16 | RLAY | RELAY THERAPEUTICS INC | $18.65 | -4.11% | 453.27% | -41.96% | $19.0M | 0.80% | — | HELD |
| 17 | ZBIO | ZENAS BIOPHARMA INC | $31.87 | -1.24% | 106.00% | 49.49% | $15.4M | 0.66% | — | HELD |
| 18 | ERAS | ERASCA INC | $17.98 | -3.77% | 1243.88% | -21.87% | $14.6M | 0.62% | — | HELD |
| 19 | EIKN | EIKON THERAPEUTICS INC | $9.29 | -3.43% | -33.66% | -9.07% | $7.8M | 0.33% | — | HELD |
| 20 | REPL | REPLIMUNE GROUP INC | $10.54 | 94.82% | -28.82% | -82.97% | $7.7M | 0.32% | — | HELD |
| 21 | ZURA | ZURA BIO LTD | $5.39 | -2.80% | 260.00% | -20.70% | $7.0M | 0.30% | — | HELD |
| 22 | PHAT | PHATHOM PHARMACEUTICALS INC | $8.99 | -0.44% | 7.66% | -74.74% | $6.9M | 0.29% | — | HELD |
| 23 | MREO | MEREO BIOPHARMA GROUP PLC | $0.34 | 6.67% | -79.76% | -87.96% | $4.4M | 0.19% | — | HELD |
| 24 | STOK | STOKE THERAPEUTICS INC | $29.11 | -3.10% | 132.69% | 14.74% | $3.3M | 0.14% | — | HELD |
| 25 | PRLD | PRELUDE THERAPEUTICS INC | $4.81 | -4.75% | 509.90% | -85.85% | $3.2M | 0.14% | — | HELD |
| 26 | IBIO | IBIO INC | $1.42 | 2.52% | 110.61% | -99.78% | $3.0M | 0.13% | — | HELD |
| 27 | HLXC | HELIX ACQUISITION CORP III USD | $10.51 | 0.00% | 2.54% | 2.14% | $2.0M | 0.09% | — | HELD |
| 28 | ATRA | ATARA BIOTHERAPEUTICS INC | $8.26 | 1.10% | -29.26% | -97.82% | $471K | 0.02% | — | HELD |
| 29 | SRZNW | SURROZEN INC | — | — | -30.59% | — | $129K | 0.01% | — | HELD |
Source: SEC EDGAR · accession 0000935836-26-000270. 13F discloses long positions only — shorts, foreign equities, and options are excluded.