The U.S. FDA issued draft guidance aimed at enabling approval pathways for personalized gene therapies targeting rare mutations. Under the proposal, a sponsor could obtain approval for one patient-specific variant using a more traditional evidence package, then later seek clearances for additional variants using laboratory data instead of running new full clinical trials each time. The agency frames the approach around an “individualized feature space” defined in the original marketing application, with the goal of replacing a one-size-fits-all trial model when patient populations are too small for feasible studies. The FDA tied the policy direction to its broader Rare Disease Framework Initiative, which is designed to set standards at the level of individual conditions. Industry executives highlighted immediate relevance. Prime Medicine’s programs were noted by analysts as potential beneficiaries, and Beam Therapeutics CEO John Evans said the concept is supported by base editing science as shares reacted to the guidance. The draft also arrives as the FDA plans a meeting on the Rare Disease Framework Initiative at its White Oak campus and recently held a rare disease summit, signaling further regulatory movement on fast, evidence-based access for mutation-defined populations.