Pfizer exercised its option to secure global rights to Beam Therapeutics’ liver‑targeted base‑editing candidate, after shifting away from in‑house gene therapy assets. The move gives Pfizer access to Beam’s liver editing platform and reflects continued major‑pharma interest in precise, in‑vivo gene editing. Beam separately disclosed BEAM‑304, a multi‑editor program targeting phenylketonuria (PKU) via liver base editing; preclinical data normalized plasma phenylalanine in mouse models and Beam plans an IND filing in 2026. The company’s strategy is to develop mutation‑specific base editors under one clinical program to cover prevalent PAH mutations in the U.S. PKU program aims to enable durable correction and diet normalization. The developments signal both strategic partnering by big pharma to re‑enter gene editing and platform maturation as companies move from ex‑vivo to liver‑directed in‑vivo editors. Regulatory filings and early clinical safety will determine how rapidly liver editing expands into rare‑disease indications.