Clover Enters into Exclusive Agreement to Commercialize Quadrivalent Seasonal Influenza Vaccine in Mainland China GlobeNewswire February 19, 2023 Clover to leverage its established and growing commercial infrastructure to exclusively distribute Adimmune’s AdimFlu-S (QIS), the only imported quadrivalent influenza vaccine approved in mainland China 1 Sasha D, Valinsky L, Hershkowitz Sikron.