[MSF Press Release] The international medical humanitarian organisation Médecins Sans Frontières (MSF) today filed a legal patent challenge at China’s State Intellectual Property Office (SIPO), requesting the invalidation of the patent granted to US pharmaceutical corporation Gilead Sciences for the oral hepatitis C medicine velpatasvir. The patent is being contested on the grounds that it involves well-known technologies, rendering it an unmerited patent under China’s patent law, which is consistent with the World Trade Organization rules.