The FDA unveiled draft guidance enabling biopharma developers to reduce or eliminate nonhuman primate testing for certain monoclonal antibodies (mAbs), signaling a policy shift in preclinical safety requirements. The guidance outlines scientific criteria and alternative approaches sponsors may use to justify limited or no primate studies for specific antibody classes and mechanisms of action. Agency documents and press coverage indicate the move aims to accelerate clinical entry and lower development costs while relying on mechanistic and in vitro data where appropriate. The draft complements ongoing efforts to modernize nonclinical paradigms and aligns with broader regulator interest in reducing animal use where scientifically supported. Biotech R&D teams should assess their mAb programs against the draft’s decision framework and prepare data packages demonstrating target specificity, cross-reactivity assessments, and robust in vitro safety pharmacology. Regulatory strategy teams will need to engage early with FDA reviewers to apply the guidance to program-specific plans.