[step Pharmaceutical: approved Clinical trial of tetravalent split Influenza virus Vaccine] June 19, according to the announcement of step Pharmaceutical, the holding subsidiary recently received a notice of drug clinical trial approval for tetravalent split influenza virus vaccine (MDCK cells) approved and issued by the State Drug Administration. It is reported that vaccination of tetravalent split influenza virus vaccine (MDCK cells) can stimulate the body to develop immunity against influenza virus, which is used to prevent influenza caused by vaccine-related influenza viruses.