Avidity Partners Management LP

Avidity Partners' $442M Q1 2026 13F is a biotech-forward long/short portfolio that dramatically concentrated around clinical-stage champions. Dianthus Therapeutics alone is 41.8% of assets, dwarfing every other holding. The most important trade of the quarter was the elimination of large-cap healthcare staples — CG Oncology, McKesson, Alnylam, Pfizer, Danaher, Thermo Fisher, Novo Nordisk, Centene, Agilent, and Kenvue — all sold outright. In their place, Avidity established fresh stakes in Enliven Therapeutics, Aktis Oncology, VIR Biotechnology, Dexcom, Humana, Tempus AI, Tenax Therapeutics, Satellos Bioscience, Gilead, and Structure Therapeutics. The portfolio now reads as a concentrated bet on near-term clinical catalysts rather than broad healthcare diversification.