NASOVAC-S4 is a quadrivalent vaccine which has evolved from a decade long legacy of NASOVAC-S & NASOVAC. NASOVAC was developed by Serum Institute during the 2009-2010 H1N1 pandemic. NASOVAC was a monovalent H1N1 vaccine which was administered to more than 2.5 million individuals during the pandemic. NASOVAC-S is a trivalent vaccine that evolved from NASOVAC, which was the precursor to NASOVAC-S4.
NASOVAC-S4 is essentially the same as trivalent NASOVAC-S of SIIPL since the same master donor virus is used except for the presence of an additional B strain & a liquid presentation. Hence, the immunogenicity, efficacy and safety data of earlier live attenuated influenza virus vaccines of SIIPL are applicable to Quadrivalent Influenza Vaccine.