We manufactured the S-892216 injectable suspension on a 6-L scale and tested its stability under two storage conditions. To identify potential stability risks, we set the dose of gamma sterilization at 200 kGy, representing an extreme condition for terminal sterilization. The known impurities A and B caused by gamma sterilization did not increase after 12 months of storage at 5°C and 25°C/60% relative humidity (Table ). Additionally, the drug particle size showed no increasing tendency and good redispersibility. Therefore, the physicochemical stability of the developed suspension formulation was considered acceptable, and long-term storage at room temperature may be feasible for the marketed formulation. This characteristic eliminates the need for high-cost cold-chain distribution, thus benefitting patients and customers. This advantage of drug quality distinguishes the S-892216 injectable suspension from other vaccines and antibody drugs in COVID-19 PrEP products.