The U.S. Food and Drug Administration ordered a pause on enrollment and placed a partial clinical hold after a patient death and multiple severe adverse events in MacroGenics’ Phase 2 study of lorigerlimab, the company disclosed. Regulators cited safety concerns tied to life‑threatening toxicities, prompting the stop‑gap action while investigators and the agency review the case. MacroGenics confirmed the hold and disclosed details about the events; the company and the FDA are coordinating to evaluate causality and potential protocol changes. The hold affects trial timelines and will delay any planned data readouts and regulatory interactions until safety questions are resolved. The episode highlights the persistent development risk in next‑generation immunotherapies and the FDA’s readiness to act on serious safety signals mid‑program, underscoring the need for sponsors to maintain robust safety monitoring and contingency plans.