MPM Bioimpact LLC
In its 13F for Q2 2025 (holdings as of June 30, 2025, filed August 14, 2025), MPM Bioimpact LLC reported 44 stock positions worth $577.2 million. Its top holding was Cullinan Therapeutics (CGEM) at 10.0% of the portfolio, followed by Madrigal Pharmaceuticals (MDGL, 5.3%) and Zai Lab Ltd.-ADR (ZLAB, 4.5%). Compared with Q1 2025, it opened 8 new positions, sold out of 7, added to 10 and reduced 20. The biggest buy was a new position in Tarsus Pharmaceuticals (TARS) and the biggest sale an exit from Lantheus (LNTH).
- Most Recent 13F
- Q2 2026
- Location
- BOSTON, MA
- CIK
- 0001687078
- Portfolio Value
- $577.2M (Q2 2025)
- SEC Filing
- 0000950123-25-008431 ↗ filed Aug 14, 2025
Holdings Value
Holdings 44 stocks · $577.2M
| CGEM Cullinan Therapeutics Inc. | 9.98% | 7,648,268 | $57.6M | No change |
| MDGL Madrigal Pharmaceuticals Inc. | 5.27% | 100,415 | $30.4M | No change |
| ZLAB Zai Lab Ltd.-ADR | 4.51% | 745,060 | $26.1M | Reduce -10.6% |
| GH Guardant Health Inc. | 3.99% | 442,656 | $23.0M | No change |
| SPRY Ars Pharmaceuticals Inc. | 3.94% | 1,303,399 | $22.7M | Reduce -0.7% |
| EWTX Edgewise Therapeutics Inc. | 3.91% | 1,720,741 | $22.6M | Add +55.7% |
| RNAM Avidity Biosciences Inc. | 3.74% | 760,022 | $21.6M | Add +6.4% |
| PTCT PTC Therapeutics Inc. | 3.71% | 438,477 | $21.4M | Reduce -0.3% |
| TRVI Trevi Therapeutics Inc. | 3.23% | 3,406,955 | $18.6M | Reduce -0.6% |
| ORIC Oric Pharmaceuticals Inc. | 3.04% | 1,729,378 | $17.6M | Add +23.6% |
| NTRA Natera Inc. | 2.90% | 98,924 | $16.7M | Reduce -37.0% |
| ALKS Alkermes PLC | 2.72% | 549,262 | $15.7M | Add +62.7% |
| MLTX Moonlake Immunotherapeutics | 2.56% | 313,571 | $14.8M | Reduce -0.8% |
| MBX MBX Biosciences Inc. | 2.56% | 1,294,416 | $14.8M | Add +14.3% |
| CMPX Compass Therapeutics Inc. | 2.53% | 5,622,505 | $14.6M | Reduce -33.4% |
| RARE Ultragenyx Pharmaceutical Inc. | 2.49% | 395,700 | $14.4M | Reduce -0.7% |
| JANX Janux Therapeutics Inc. | 2.46% | 614,282 | $14.2M | Add +8.3% |
| TARS Tarsus Pharmaceuticals Inc. | 2.40% | 341,496 | $13.8M | New |
| DYN Dyne Therapeutics Inc. | 2.39% | 1,446,361 | $13.8M | New |
| VERA Vera Therapeutics Inc. | 2.30% | 563,075 | $13.3M | Add +35.5% |
| CRNX Crinetics Pharmaceuticals Inc. | 2.14% | 428,975 | $12.3M | Reduce -32.1% |
| RVMD Revolution Medicines Inc. | 2.01% | 315,722 | $11.6M | Reduce -0.4% |
| AKBA Akebia Therapeutics Inc. | 1.82% | 2,889,125 | $10.5M | New |
| OLMA Olema Pharmaceuticals Inc. | 1.76% | 2,378,762 | $10.1M | Reduce -18.8% |
| XENE Xenon Pharmaceuticals Inc. | 1.75% | 323,398 | $10.1M | Add +6.6% |
| WVE Wave Life Sciences Ltd. | 1.70% | 1,505,262 | $9.8M | Reduce -0.3% |
| DBVT DBV Technologies SA-Spon ADR | 1.67% | 1,054,504 | $9.6M | New |
| CNTX Context Therapeutics Inc. | 1.67% | 14,705,882 | $9.6M | No change |
| RCKT Rocket Pharmaceuticals Inc. | 1.66% | 3,903,081 | $9.6M | Add +141.2% |
| REPL Replimune Group Inc. | 1.58% | 983,780 | $9.1M | Reduce -0.3% |
| NUVB Nuvation Bio Inc. | 1.56% | 4,622,590 | $9.0M | Reduce -0.6% |
| STOK Stoke Therapeutics Inc. | 1.55% | 789,698 | $9.0M | Add +13.8% |
| SLDB Solid Biosciences Inc. | 1.38% | 1,634,569 | $8.0M | Reduce -0.5% |
| RLAY Relay Therapeutics Inc. | 1.37% | 2,282,680 | $7.9M | Reduce -0.6% |
| RNAC Cartesian Therapeutics Inc. | 1.24% | 686,007 | $7.1M | Reduce -13.3% |
| TSHA Taysha Gene Therapies Inc. | 1.18% | 2,953,562 | $6.8M | New |
| SRPT Sarepta Therapeutics Inc. | 0.95% | 321,696 | $5.5M | New |
| SLNO Soleno Therapeutics Inc. | 0.73% | 50,000 | $4.2M | New |
| VERU Veru Inc. | 0.50% | 4,911,948 | $2.9M | Reduce -25.5% |
| HOWL Werewolf Therapeutics Inc. | 0.45% | 2,408,810 | $2.6M | No change |
| DSGN Design Therapeutics Inc. | 0.32% | 555,187 | $1.9M | Reduce -1.4% |
| RPTX Repare Therapeutics Inc. | 0.20% | 819,924 | $1.1M | No change |
| ADAPY Adaptimmune Therapeutics-ADR | 0.18% | 4,411,821 | $1.1M | Reduce -9.9% |
| ACLX Arcellx Inc. | 0.00% | 37 | $2K | New |
Portfolio Sells Q1 2025 → Q2 2025
| LNTH Lantheus Holdings Inc. | Sold out | 0.00% | −3.90 |
| UTHR United Therapeutics Corp. | Sold out | 0.00% | −3.12 |
| ITOS Iteos Therapeutics Inc. | Sold out | 0.00% | −1.79 |
| TWST Twist Bioscience Corp. | Sold out | 0.00% | −1.76 |
| IOVA Iovance Biotherapeutics Inc. | Sold out | 0.00% | −1.55 |
| CRNX Crinetics Pharmaceuticals Inc. | Reduce -32.1% | 2.14% | −1.51 |
| IDYA Ideaya Biosciences Inc. | Sold out | 0.00% | −1.21 |
| NTRA Natera Inc. | Reduce -37.0% | 2.90% | −0.92 |
| ZLAB Zai Lab Ltd.-ADR | Reduce -10.6% | 4.51% | −0.67 |
| RNAC Cartesian Therapeutics Inc. | Reduce -13.3% | 1.24% | −0.56 |
| TRVI Trevi Therapeutics Inc. | Reduce -0.6% | 3.23% | −0.48 |
| WVE Wave Life Sciences Ltd. | Reduce -0.3% | 1.70% | −0.40 |
| CMPX Compass Therapeutics Inc. | Reduce -33.4% | 2.53% | −0.22 |
| PTCT PTC Therapeutics Inc. | Reduce -0.3% | 3.71% | −0.14 |
| OLMA Olema Pharmaceuticals Inc. | Reduce -18.8% | 1.76% | −0.14 |
| REPL Replimune Group Inc. | Reduce -0.3% | 1.58% | −0.07 |
| VERU Veru Inc. | Reduce -25.5% | 0.50% | −0.06 |
| ALXO Alx Oncology Holdings Inc. | Sold out | 0.00% | −0.06 |
| DSGN Design Therapeutics Inc. | Reduce -1.4% | 0.32% | −0.05 |
| RARE Ultragenyx Pharmaceutical Inc. | Reduce -0.7% | 2.49% | +0.01 |
| ADAPY Adaptimmune Therapeutics-ADR | Reduce -9.9% | 0.18% | +0.02 |
| RVMD Revolution Medicines Inc. | Reduce -0.4% | 2.01% | +0.09 |
| NUVB Nuvation Bio Inc. | Reduce -0.6% | 1.56% | +0.15 |
| RLAY Relay Therapeutics Inc. | Reduce -0.6% | 1.37% | +0.33 |
| SLDB Solid Biosciences Inc. | Reduce -0.5% | 1.38% | +0.33 |
| MLTX Moonlake Immunotherapeutics | Reduce -0.8% | 2.56% | +0.44 |
| SPRY Ars Pharmaceuticals Inc. | Reduce -0.7% | 3.94% | +1.10 |
Portfolio Buys Q1 2025 → Q2 2025
| TARS Tarsus Pharmaceuticals Inc. | New | 2.40% | +2.40 |
| DYN Dyne Therapeutics Inc. | New | 2.39% | +2.39 |
| AKBA Akebia Therapeutics Inc. | New | 1.82% | +1.82 |
| ORIC Oric Pharmaceuticals Inc. | Add +23.6% | 3.04% | +1.70 |
| DBVT DBV Technologies SA-Spon ADR | New | 1.67% | +1.67 |
| TSHA Taysha Gene Therapies Inc. | New | 1.18% | +1.18 |
| MBX MBX Biosciences Inc. | Add +14.3% | 2.56% | +1.12 |
| SRPT Sarepta Therapeutics Inc. | New | 0.95% | +0.95 |
| ALKS Alkermes PLC | Add +62.7% | 2.72% | +0.81 |
| STOK Stoke Therapeutics Inc. | Add +13.8% | 1.55% | +0.76 |
| SLNO Soleno Therapeutics Inc. | New | 0.73% | +0.73 |
| VERA Vera Therapeutics Inc. | Add +35.5% | 2.30% | +0.58 |
| RNAM Avidity Biosciences Inc. | Add +6.4% | 3.74% | +0.12 |
| XENE Xenon Pharmaceuticals Inc. | Add +6.6% | 1.75% | +0.00 |
| ACLX Arcellx Inc. | New | 0.00% | +0.00 |
| JANX Janux Therapeutics Inc. | Add +8.3% | 2.46% | −0.17 |
| RCKT Rocket Pharmaceuticals Inc. | Add +141.2% | 1.66% | −0.20 |
| EWTX Edgewise Therapeutics Inc. | Add +55.7% | 3.91% | −0.27 |
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 |