MPM Bioimpact LLC
In its 13F for Q3 2025 (holdings as of September 30, 2025, filed November 14, 2025), MPM Bioimpact LLC reported 40 stock positions worth $610.9 million. Its top holding was Madrigal Pharmaceuticals (MDGL) at 7.5% of the portfolio, followed by Cullinan Therapeutics (CGEM, 7.4%) and Avidity Biosciences (RNAM, 5.4%). Compared with Q2 2025, it opened 7 new positions, sold out of 11, added to 4 and reduced 2. The biggest buy was a new position in Syndax Pharmaceuticals (SNDX) and the biggest sale an exit from Guardant Health (GH).
- Most Recent 13F
- Q2 2026
- Location
- BOSTON, MA
- CIK
- 0001687078
- Portfolio Value
- $610.9M (Q3 2025)
- SEC Filing
- 0001193125-25-283112 ↗ filed Nov 14, 2025
Holdings Value
Holdings 40 stocks · $610.9M
| MDGL Madrigal Pharmaceuticals Inc. | 7.54% | 100,415 | $46.1M | No change |
| CGEM Cullinan Therapeutics Inc. | 7.42% | 7,648,268 | $45.4M | No change |
| RNAM Avidity Biosciences Inc. | 5.42% | 760,022 | $33.1M | No change |
| TRVI Trevi Therapeutics Inc. | 5.10% | 3,406,955 | $31.2M | No change |
| EWTX Edgewise Therapeutics Inc. | 4.57% | 1,720,741 | $27.9M | No change |
| PTCT PTC Therapeutics Inc. | 4.41% | 438,477 | $26.9M | No change |
| ZLAB Zai Lab Ltd.-ADR | 4.13% | 745,060 | $25.3M | No change |
| SNDX Syndax Pharmaceuticals Inc. | 3.46% | 1,375,674 | $21.2M | New |
| ORIC Oric Pharmaceuticals Inc. | 3.40% | 1,729,378 | $20.8M | No change |
| TARS Tarsus Pharmaceuticals Inc. | 3.32% | 341,496 | $20.3M | No change |
| XENE Xenon Pharmaceuticals Inc. | 3.31% | 503,398 | $20.2M | Add +55.7% |
| STOK Stoke Therapeutics Inc. | 3.04% | 789,698 | $18.6M | No change |
| DYN Dyne Therapeutics Inc. | 3.00% | 1,446,361 | $18.3M | No change |
| CMPX Compass Therapeutics Inc. | 2.91% | 5,075,970 | $17.8M | Reduce -9.7% |
| ALKS Alkermes PLC | 2.70% | 549,262 | $16.5M | No change |
| VERA Vera Therapeutics Inc. | 2.68% | 563,075 | $16.4M | No change |
| NTRA Natera Inc. | 2.61% | 98,924 | $15.9M | No change |
| JANX Janux Therapeutics Inc. | 2.46% | 614,282 | $15.0M | No change |
| RVMD Revolution Medicines Inc. | 2.41% | 315,722 | $14.7M | No change |
| CNTX Context Therapeutics Inc. | 2.33% | 14,705,882 | $14.2M | No change |
| SRPT Sarepta Therapeutics Inc. | 2.21% | 700,000 | $13.5M | Add +117.6% |
| SPRY Ars Pharmaceuticals Inc. | 2.14% | 1,303,399 | $13.1M | No change |
| RCKT Rocket Pharmaceuticals Inc. | 2.08% | 3,903,381 | $12.7M | Add +0.0% |
| RLAY Relay Therapeutics Inc. | 1.95% | 2,282,680 | $11.9M | No change |
| RARE Ultragenyx Pharmaceutical Inc. | 1.95% | 395,700 | $11.9M | No change |
| WVE Wave Life Sciences Ltd. | 1.80% | 1,505,262 | $11.0M | No change |
| DBVT DBV Technologies SA-Spon ADR | 1.73% | 1,054,504 | $10.5M | No change |
| SLNO Soleno Therapeutics Inc. | 1.66% | 150,000 | $10.1M | Add +200.0% |
| SLDB Solid Biosciences Inc. | 1.65% | 1,634,569 | $10.1M | No change |
| AKBA Akebia Therapeutics Inc. | 1.29% | 2,889,125 | $7.9M | No change |
| HOWL Werewolf Therapeutics Inc. | 0.78% | 2,408,810 | $4.7M | No change |
| LQDA Liquidia Corp. | 0.74% | 200,000 | $4.5M | New |
| PVLA Palvella Therapeutics Inc. | 0.69% | 67,423 | $4.2M | New |
| DSGN Design Therapeutics Inc. | 0.68% | 555,187 | $4.2M | No change |
| RNAC Cartesian Therapeutics Inc. | 0.64% | 380,000 | $3.9M | Reduce -44.6% |
| ENGN Engene Holdings Inc. | 0.59% | 530,299 | $3.6M | New |
| URGN Urogen Pharma Ltd. | 0.44% | 135,000 | $2.7M | New |
| RAPP Rapport Therapeutics Inc. | 0.35% | 71,807 | $2.1M | New |
| RPTX Repare Therapeutics Inc. | 0.24% | 819,924 | $1.4M | No change |
| ASMB Assembly Biosciences Inc. | 0.17% | 39,665 | $1.0M | New |
Portfolio Sells Q2 2025 → Q3 2025
| GH Guardant Health Inc. | Sold out | 0.00% | −3.99 |
| MLTX Moonlake Immunotherapeutics | Sold out | 0.00% | −2.56 |
| MBX MBX Biosciences Inc. | Sold out | 0.00% | −2.56 |
| CRNX Crinetics Pharmaceuticals Inc. | Sold out | 0.00% | −2.14 |
| OLMA Olema Pharmaceuticals Inc. | Sold out | 0.00% | −1.76 |
| REPL Replimune Group Inc. | Sold out | 0.00% | −1.58 |
| NUVB Nuvation Bio Inc. | Sold out | 0.00% | −1.56 |
| TSHA Taysha Gene Therapies Inc. | Sold out | 0.00% | −1.18 |
| RNAC Cartesian Therapeutics Inc. | Reduce -44.6% | 0.64% | −0.60 |
| VERU Veru Inc. | Sold out | 0.00% | −0.50 |
| ADAPY Adaptimmune Therapeutics-ADR | Sold out | 0.00% | −0.18 |
| ACLX Arcellx Inc. | Sold out | 0.00% | −0.00 |
| CMPX Compass Therapeutics Inc. | Reduce -9.7% | 2.91% | +0.38 |
Portfolio Buys Q2 2025 → Q3 2025
| SNDX Syndax Pharmaceuticals Inc. | New | 3.46% | +3.46 |
| XENE Xenon Pharmaceuticals Inc. | Add +55.7% | 3.31% | +1.55 |
| SRPT Sarepta Therapeutics Inc. | Add +117.6% | 2.21% | +1.25 |
| SLNO Soleno Therapeutics Inc. | Add +200.0% | 1.66% | +0.93 |
| LQDA Liquidia Corp. | New | 0.74% | +0.74 |
| PVLA Palvella Therapeutics Inc. | New | 0.69% | +0.69 |
| ENGN Engene Holdings Inc. | New | 0.59% | +0.59 |
| URGN Urogen Pharma Ltd. | New | 0.44% | +0.44 |
| RCKT Rocket Pharmaceuticals Inc. | Add +0.0% | 2.08% | +0.43 |
| RAPP Rapport Therapeutics Inc. | New | 0.35% | +0.35 |
| ASMB Assembly Biosciences Inc. | New | 0.17% | +0.17 |
All Filings
| Quarter | Positions | 13F Reported Value | Top Holdings |
|---|---|---|---|
| Q2 2026 | 37 | $1.6B | CGEM, AKTS, LQDA, RVMD, CORT |
| Q1 2026 | 41 | $1.3B | DBVT, CGEM, AKTS, LQDA, ALMS |
| Q4 2025 | 38 | $874.0M | CGEM, MDGL, LQDA, TRVI, EWTX |
| Q3 2025 | 40 | $610.9M | MDGL, CGEM, RNAM, TRVI, EWTX |
| Q2 2025 | 44 | $577.2M | CGEM, MDGL, ZLAB, GH, SPRY |
| Q1 2025 | 43 | $581.7M | CGEM, MDGL, ZLAB, EWTX, LNTH |
| Q4 2024 | 47 | $704.4M | CGEM, CRNX, EWTX, INSM, NTRA |
| Q3 2024 | 43 | $666.6M | CGEM, INSM, OLMA, RNAM, CRNX |
| Q2 2024 | 44 | $643.5M | CGEM, INSM, OLMA, ITOS, CRNX |
| Q1 2024 | 38 | $622.0M | CGEM, GERN, IOVA, ZNTL, ITOS |