Atlas Venture Life Science Advisors, LLC
In its 13F for Q1 2026 (holdings as of March 31, 2026, filed May 14, 2026), Atlas Venture Life Science Advisors, LLC reported 6 stock positions worth $790.0 million. Its top holding was Kymera Therapeutics (KYMR) at 48.3% of the portfolio, followed by Dyne Therapeutics (DYN, 21.0%) and Sionna Therapeutics (SION, 15.2%). Compared with Q4 2025, it sold out of 2 and reduced 1. The biggest sale was an exit from Day One Biopharmaceuticals I (DAWN).
- Most Recent 13F
- Q2 2026
- Location
- CAMBRIDGE, MA
- CIK
- 0001917529
- Portfolio Value
- $790.0M (Q1 2026)
- SEC Filing
- 0001104659-26-061232 ↗ filed May 14, 2026
Holdings Value
Holdings 6 stocks · $790.0M
| KYMR Kymera Therapeutics Inc. | 48.26% | 4,578,008 | $381.3M | Reduce -1.8% |
| DYN Dyne Therapeutics Inc. | 20.95% | 9,130,465 | $165.5M | No change |
| SION Sionna Therapeutics Inc. | 15.20% | 2,995,602 | $120.1M | No change |
| IRON Disc Medicine Inc. | 12.25% | 1,513,875 | $96.8M | No change |
| QTTB Q32 Bio Inc. | 1.70% | 2,092,106 | $13.4M | No change |
| KRRO Korro Bio Inc. | 1.63% | 1,137,149 | $12.9M | No change |
Portfolio Sells Q4 2025 → Q1 2026
Portfolio Buys Q4 2025 → Q1 2026
| None this quarter. | |||
All Filings
| Quarter | Positions | 13F Reported Value | Top Holdings |
|---|---|---|---|
| Q2 2026 | 7 | $881.3M | KYMR, DYN, SION, KLRA, IRON |
| Q1 2026 | 6 | $790.0M | KYMR, DYN, SION, IRON, QTTB |
| Q4 2025 | 8 | $865.2M | KYMR, DYN, SION, IRON, DAWN |
| Q3 2025 | 9 | $752.6M | KYMR, IRON, DYN, SION, KRRO |
| Q2 2025 | 11 | $662.4M | KYMR, IRON, DYN, SION, THRD |
| Q1 2025 | 13 | $521.8M | KYMR, IRON, DYN, DAWN, SION |
| Q4 2024 | 13 | $819.7M | KYMR, DYN, IRON, THRD, DAWN |
| Q3 2024 | 14 | $1.1B | DYN, KYMR, THRD, IRON, QTTB |
| Q2 2024 | 15 | $949.6M | DYN, KYMR, THRD, IRON, DAWN |
| Q1 2024 | 16 | $1.1B | DYN, KYMR, IRON, DAWN, THRD |