Baker Bros. Advisors LP

In its 13F for Q1 2025 (holdings as of March 31, 2025, filed May 15, 2025), Baker Bros. Advisors LP reported 87 stock positions worth $8.9 billion. Its top holding was Beone Medicines Ltd.-ADR (ONC) at 26.8% of the portfolio, followed by Incyte (INCY, 20.8%) and Acadia Pharmaceuticals (ACAD, 8.0%). Compared with Q4 2024, it opened 4 new positions, sold out of 9, added to 11 and reduced 16. The biggest buy was Insmed (INSM, shares +7%) and the biggest sale Rhythm Pharmaceuticals (RYTM, shares −8%).

Most Recent 13F
Q2 2026
Location
NEW YORK, NY
CIK
0001263508
Portfolio Value
$8.9B (Q1 2025)
SEC Filing
0001104659-25-049518 ↗ filed May 15, 2025

Holdings Value

0$5.0B$10.0B$15.0B$20.0B Q1 2024: $8.0B Q1 2024 Q2 2024: $7.7B Q2 2024 Q3 2024: $9.6B Q3 2024 Q4 2024: $9.2B Q4 2024 Q1 2025: $8.9B $8.9B Q1 2025 Q2 2025: $10.3B Q2 2025 Q3 2025: $13.8B Q3 2025 Q4 2025: $17.0B Q4 2025 Q1 2026: $17.4B Q1 2026 Q2 2026: $19.9B Q2 2026

Holdings 87 stocks · $8.9B
ONC Beone Medicines Ltd.-ADR filed as BEIGENE LTD 26.80% 8,799,053 $2.4B Reduce -7.7%
INCY Incyte Corp. 20.83% 30,739,953 $1.9B Add +0.0%
ACAD Acadia Pharmaceuticals Inc. 7.97% 42,877,916 $712.2M No change
MDGL Madrigal Pharmaceuticals Inc. 7.32% 1,974,590 $654.0M No change
SMMT Summit Therapeutics Inc. 5.27% 24,424,865 $471.2M No change
INSM Insmed Inc. 4.59% 5,380,626 $410.5M Add +7.5%
RYTM Rhythm Pharmaceuticals Inc. 3.32% 5,604,483 $296.9M Reduce -7.9%
RVMD Revolution Medicines Inc. 3.14% 7,936,972 $280.7M No change
KYMR Kymera Therapeutics Inc. 1.84% 5,995,929 $164.1M No change
ALKS Alkermes PLC 1.66% 4,483,285 $148.0M Add +7.2%
EWTX Edgewise Therapeutics Inc. 1.52% 6,155,940 $135.4M No change
REPL Replimune Group Inc. 1.21% 11,045,336 $107.7M No change
IMVT Immunovant Inc. 1.04% 5,457,881 $93.3M Add +219.6%
BCYC Bicycle Therapeutics PLC-ADR 1.03% 10,885,357 $92.4M No change
IMCR Immunocore Holdings PLC-ADR 0.77% 2,322,656 $68.9M Add +53.3%
KNSA Kiniksa Pharmaceuticals Inte 0.70% 2,818,323 $62.6M No change
ABCL Abcellera Biologics Inc. 0.69% 27,525,640 $61.4M No change
RARE Ultragenyx Pharmaceutical Inc. 0.64% 1,576,114 $57.1M No change
DNLI Denali Therapeutics Inc. 0.57% 3,731,695 $50.7M No change
KOD Kodiak Sciences Inc. 0.54% 17,310,490 $48.6M No change
NRIX Nurix Therapeutics Inc. 0.52% 3,882,125 $46.1M No change
ARGX Argenx SE - ADR 0.52% 77,760 $46.0M Reduce -30.5%
TRDA Entrada Therapeutics Inc. 0.49% 4,865,819 $44.0M No change
CELC Celcuity Inc. 0.48% 4,257,735 $43.0M Add +59.0%
GRAL Grail Inc. 0.47% 1,630,125 $41.6M No change
ROIV Roivant Sciences Ltd. 0.43% 3,767,773 $38.0M No change
IMTX Immatics NV 0.37% 7,275,830 $32.8M No change
STOK Stoke Therapeutics Inc. 0.34% 4,633,838 $30.8M No change
CERS Cerus Corp. 0.30% 19,351,087 $26.9M Reduce -0.7%
PCVX Vaxcyte Inc. 0.27% 640,885 $24.2M Add +1211.0%
GLUE Monte Rosa Therapeutics Inc. 0.26% 4,916,095 $22.8M No change
CRSP Crispr Therapeutics AG 0.25% 654,099 $22.3M Reduce -50.0%
AKRO Akero Therapeutics Inc. 0.25% 548,713 $22.2M Reduce -50.0%
SERA Sera Prognostics Inc. Class A 0.23% 5,498,170 $20.2M Add +1.2%
CNTA Centessa Pharmaceuticals Ltd. 0.20% 1,227,178 $17.6M No change
NGNE Neurogene Inc. 0.19% 1,486,200 $17.4M Add +120.4%
IDYA Ideaya Biosciences Inc. 0.19% 1,062,123 $17.4M No change
VRNA Verona Pharma Ltd. 0.16% 223,843 $14.2M New
CADL Candel Therapeutics Inc. 0.15% 2,437,189 $13.8M Reduce -18.3%
PRAX Praxis Precision Medicines I 0.14% 331,533 $12.6M No change
TSVT 2SEVENTY Bio Inc. 0.14% 2,497,526 $12.3M No change
XENE Xenon Pharmaceuticals Inc. 0.13% 347,408 $11.7M Reduce -65.0%
BCAX Bicara Therapeutics Inc. 0.12% 833,333 $10.9M No change
IONS Ionis Pharmaceuticals Inc. 0.12% 357,915 $10.8M No change
DBVT DBV Technologies SA-Spon ADR 0.11% 1,461,425 $10.0M No change
ALMS Alumis Inc. 0.11% 1,562,500 $9.6M No change
MRUS Merus NV 0.11% 223,500 $9.4M Reduce -50.3%
PRLD Prelude Therapeutics Inc. 0.09% 10,123,824 $7.8M No change
VERV Verve Therapeutics Inc. 0.09% 1,691,530 $7.7M No change
RCKT Rocket Pharmaceuticals Inc. 0.08% 1,097,079 $7.3M Add +1030.1%
XNCR Xencor Inc. 0.08% 670,431 $7.1M No change
DYN Dyne Therapeutics Inc. 0.08% 672,096 $7.0M No change
KALA Kala Bio Inc. 0.08% 1,201,894 $6.9M No change
DSGN Design Therapeutics Inc. 0.08% 1,743,725 $6.7M No change
GPCR Structure Therapeutics Inc. 0.07% 361,565 $6.3M No change
TSHA Taysha Gene Therapies Inc. 0.06% 4,004,756 $5.6M No change
RGLS Regulus Therapeutics Inc. 0.05% 2,694,044 $4.7M New
IGMS Igm Biosciences Inc. 0.05% 4,095,257 $4.7M Add +0.0%
NTLA Intellia Therapeutics Inc. 0.05% 644,116 $4.6M No change
CLDX Celldex Therapeutics Inc. 0.05% 247,644 $4.5M No change
SION Sionna Therapeutics Inc. 0.05% 400,000 $4.2M New
BNTX Biontech SE-ADR 0.05% 45,031 $4.1M No change
TCRX Tscan Therapeutics Inc. 0.04% 2,784,792 $3.8M No change
IRON Disc Medicine Inc. 0.04% 77,050 $3.8M No change
VIR Vir Biotechnology Inc. 0.04% 542,539 $3.5M Reduce -50.0%
SANA Sana Biotechnology Inc. 0.04% 2,030,949 $3.4M Reduce -14.7%
SGMT Sagimet Biosciences Inc. Class A 0.03% 952,996 $3.1M No change
RLAY Relay Therapeutics Inc. 0.03% 1,160,117 $3.0M No change
WVE Wave Life Sciences Ltd. 0.03% 344,063 $2.8M No change
FATE Fate Therapeutics Inc. 0.03% 3,258,402 $2.6M No change
SKYE Skye Bioscience Inc. 0.03% 1,450,638 $2.3M No change
TARA Protara Therapeutic Inc. 0.03% 536,832 $2.3M No change
ELVN Enliven Therapeutics Inc. 0.03% 114,833 $2.3M No change
CTNM Contineum Therapeutics Inc. Class A 0.02% 312,500 $2.2M No change
PRME Prime Medicine Inc. 0.02% 1,028,466 $2.0M No change
TECX Tectonic Therapeutic Inc. 0.02% 100,000 $1.8M New
VTVT VTV Therapeutics Inc. Class A 0.02% 97,314 $1.7M No change
CMPX Compass Therapeutics Inc. 0.01% 547,498 $1.0M Reduce -64.8%
NMRA Neumora Therapeutics Inc. 0.01% 1,034,600 $1.0M No change
HOOK Hookipa Pharma Inc. 0.01% 812,814 $878K No change
GBIO Generation Bio Co. 0.01% 1,944,945 $788K No change
ALGS Aligos Therapeutics Inc. 0.01% 83,055 $685K No change
CYPH Cypherpunk Technologies Inc. filed as LEAP THERAPEUTICS INC 0.00% 404,744 $123K Reduce -65.5%
IPSC Century Therapeutics Inc. 0.00% 241,684 $115K Reduce -69.7%
TYRA Tyra Biosciences Inc. 0.00% 10,607 $99K No change
ACRV Acrivon Therapeutics Inc. 0.00% 22,809 $46K Reduce -56.9%
CYVNY Ceryvyn Therapeutics-ADR filed as OPTHEA LTD 0.00% 2,087,320 $0 Reduce -4.0%
Other holdings (2): bonds, preferreds, convertibles and warrants · $101.6M (not counted above)
SecurityClassShares / PrincipalValueChange
INSMED INC (INSM 0.75 06/01/28) NOTE 0.750% 6/0 · principal 42,850,000$101.6MNo change
SRZNW Surrozen Inc.-CW25 *W EXP 08/01/203 833,333$25KNo change

Total filed on the 13F, all lines: $9.0B.

Portfolio Sells Q4 2024 → Q1 2025
RYTM Rhythm Pharmaceuticals Inc. Reduce -7.9% 3.32% −0.36
CRSP Crispr Therapeutics AG Reduce -50.0% 0.25% −0.31
XENE Xenon Pharmaceuticals Inc. Reduce -65.0% 0.13% −0.29
KRYS Krystal Biotech Inc. Sold out 0.00% −0.29
ARGX Argenx SE - ADR Reduce -30.5% 0.52% −0.23
CADL Candel Therapeutics Inc. Reduce -18.3% 0.15% −0.13
MRUS Merus NV Reduce -50.3% 0.11% −0.10
CYVNY Ceryvyn Therapeutics-ADR Reduce -4.0% 0.00% −0.09
MIRM Mirum Pharmaceuticals Inc. Sold out 0.00% −0.09
ARVN Arvinas Inc. Sold out 0.00% −0.08
AKRO Akero Therapeutics Inc. Reduce -50.0% 0.25% −0.08
BMEA Biomea Fusion Inc. Sold out 0.00% −0.06
VIR Vir Biotechnology Inc. Reduce -50.0% 0.04% −0.05
CYPH Cypherpunk Technologies Inc. Reduce -65.5% 0.00% −0.04
ARCT Arcturus Therapeutics Holdin Sold out 0.00% −0.03
CERS Cerus Corp. Reduce -0.7% 0.30% −0.02
MERSANA THERAPEUTICS INC Sold out 0.00% −0.02
CMPX Compass Therapeutics Inc. Reduce -64.8% 0.01% −0.01
PTCT PTC Therapeutics Inc. Sold out 0.00% −0.01
IPSC Century Therapeutics Inc. Reduce -69.7% 0.00% −0.01
PMVP PMV Pharmaceuticals Inc. Sold out 0.00% −0.01
SANA Sana Biotechnology Inc. Reduce -14.7% 0.04% −0.00
ACRV Acrivon Therapeutics Inc. Reduce -56.9% 0.00% −0.00
FHTX Foghorn Therapeutics Inc. Sold out 0.00% −0.00
ONC Beone Medicines Ltd.-ADR Reduce -7.7% 26.80% +7.75

Portfolio Buys Q4 2024 → Q1 2025
INSM Insmed Inc. Add +7.5% 4.59% +0.85
IMVT Immunovant Inc. Add +219.6% 1.04% +0.59
ALKS Alkermes PLC Add +7.2% 1.66% +0.36
IMCR Immunocore Holdings PLC-ADR Add +53.3% 0.77% +0.29
PCVX Vaxcyte Inc. Add +1211.0% 0.27% +0.23
VRNA Verona Pharma Ltd. New 0.16% +0.16
CELC Celcuity Inc. Add +59.0% 0.48% +0.10
RCKT Rocket Pharmaceuticals Inc. Add +1030.1% 0.08% +0.07
RGLS Regulus Therapeutics Inc. New 0.05% +0.05
SION Sionna Therapeutics Inc. New 0.05% +0.05
NGNE Neurogene Inc. Add +120.4% 0.19% +0.03
TECX Tectonic Therapeutic Inc. New 0.02% +0.02
IGMS Igm Biosciences Inc. Add +0.0% 0.05% −0.22
SERA Sera Prognostics Inc. Class A Add +1.2% 0.23% −0.25
INCY Incyte Corp. Add +0.0% 20.83% −2.15

Notes & Other Activity Q4 2024 → Q1 2025
IONIS PHARMACEUTICALS IN (IONS 1.75 06/15/28) NOTE 1.750% 6/1 · principal Sold out 30,000,000 $29.5Mbefore exit

Bonds, preferreds, convertibles and warrants; not part of the stock holdings or percentages above.

All Filings

QuarterPositions13F Reported ValueTop Holdings
Q2 2026 82$19.9BINCY, ONC, RVMD, MDGL, ACAD
Q1 2026 83$17.4BINCY, ONC, INSM, MDGL, ACAD
Q4 2025 84$17.0BINCY, ONC, MDGL, INSM, ACAD
Q3 2025 89$13.8BONC, INCY, MDGL, INSM, ACAD
Q2 2025 88$10.3BONC, INCY, ACAD, INSM, SMMT
Q1 2025 87$8.9BONC, INCY, ACAD, MDGL, SMMT
Q4 2024 92$9.2BINCY, ONC, ACAD, MDGL, SMMT
Q3 2024 91$9.6BONC, INCY, ACAD, SMMT, MDGL
Q2 2024 92$7.7BINCY, ONC, ACAD, MDGL, RVMD
Q1 2024 86$8.0BINCY, ONC, ACAD, MDGL, RYTM