EcoR1 Capital, LLC
CIK 1587114 · Holdings on Dec 31, 2023 · First reported Feb 14, 2024
Top ten holdings
Q4 2023- APLS17.37%
- MRTX11.28%
- PRTA10.93%
- ARVN7.19%
- LKFT6.08%
- ACAD4.87%
- ANAB4.18%
- ZYME3.62%
- TNGX3.43%
- JAZZ3.24%
Share classes counted separately72.19%
Portfolio value by quarter
What changed this quarter?
Within preview · weight change- PRTAWeight decreased · -8.11 pp19.04% → 10.93%Shares 0 (0.00%)
- ARVNWeight increased · +3.53 pp3.66% → 7.19%Shares +1.26M (+23.04%)
- APLSWeight increased · +3.25 pp14.12% → 17.37%Shares +273.21K (+2.51%)
Weight = security value ÷ total reported holdings value. Changes are in percentage points; price moves also affect weights, so they are not trade sizes.
Top 10 holdings 30
USD · B = billion · M = million; expand a row for exact values| # | Security | Value | Weight | Quantity | Weight / quantity change | Activity | |
|---|---|---|---|---|---|---|---|
| 01 | APLSAPELLIS PHARMACEUTICALS INC View history and evidence | $668.82M | 17.37% | 11.17M shares | 14.12% → 17.37%+3.25 pp +273.21K (+2.51%) | Added | ↗▾ |
| 02 | MRTXMIRATI THERAPEUTICS INC View history and evidence | $434.57M | 11.28% | 7.40M shares | 8.53% → 11.28%+2.75 pp +1.65M (+28.68%) | Added | ↗▾ |
| 03 | PRTAPROTHENA CORP PLCSHS View history and evidence | $420.97M | 10.93% | 11.58M shares | 19.04% → 10.93%-8.11 pp 0 (0.00%) | Unchanged | ↗▾ |
| 04 | ARVNARVINAS INC View history and evidence | $276.86M | 7.19% | 6.73M shares | 3.66% → 7.19%+3.53 pp +1.26M (+23.04%) | Added | ↗▾ |
| 05 | LKFTLAKEFRONT BIOTHERAPEUTIC-ADRSPON ADR View history and evidence | $233.99M | 6.08% | 5.76M shares | 6.77% → 6.08%-0.69 pp 0 (0.00%) | Unchanged | ↗▾ |
| 06 | ACADACADIA PHARMACEUTICALS INC View history and evidence | $187.59M | 4.87% | 5.99M shares | 4.25% → 4.87%+0.62 pp 0 (0.00%) | Unchanged | ↗▾ |
| 07 | ANABANAPTYSBIO INC View history and evidence | $161.10M | 4.18% | 7.52M shares | 4.60% → 4.18%-0.42 pp 0 (0.00%) | Unchanged | ↗▾ |
| 08 | ZYMEZYMEWORKS INC View history and evidence | $139.62M | 3.62% | 13.44M shares | 2.90% → 3.62%+0.72 pp 0 (0.00%) | Unchanged | ↗▾ |
| 09 | TNGXTANGO THERAPEUTICS INC View history and evidence | $131.97M | 3.43% | 13.33M shares | 3.34% → 3.43%+0.09 pp +4.61M (+52.85%) | Added | ↗▾ |
| 10 | JAZZJAZZ PHARMACEUTICALS PLCSHS USD View history and evidence | $124.72M | 3.24% | 1.01M shares | 1.62% → 3.24%+1.62 pp +645.54K (+175.22%) | Added | ↗▾ |
Options overlay 0
No options reported this quarter.
Exited positions 10
| Security | Type | Shares out | Value out | Previous filing | This filing |
|---|---|---|---|---|---|
| SWTX SPRINGWORKS THERAPEUTICS INC | Non-derivative | -3,460,208 | -$80.00M | SEC filing ↗ | SEC filing ↗ |
| RLAY RELAY THERAPEUTICS INC | Non-derivative | -4,163,824 | -$35.02M | SEC filing ↗ | SEC filing ↗ |
| APLS APELLIS PHARMACEUTICALS INC | Call | -732,500 | -$27.86M | SEC filing ↗ | SEC filing ↗ |
3 / 10 preview exits. Up to 30 exit records are previewed. Exit means absent from the current filing; execution date, price and proceeds are unknown.
Every number has a source.
CIK 1587114 · Period 2023-12-31
Data loaded 2026-09-23 · First reported 2024-02-14
Amendments and versions
{
"amendments_merged": null,
"prior_versions": null,
"cover_table_value": 3851537802
}Research all 51 reported holdings.
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