Study vaccines
ADENOVIRUS
SII-NVX-CoV2373 (SARS-CoV-2 recombinant spike protein nanoparticle vaccine with Matrix-M™ adjuvant, Serum Institute of India Pvt. Ltd. [SIIPL]), was available as a ready to use liquid formulation. Each single dose of 0.5 mL contained 5 μg antigen and 50 μg Matrix-M adjuvant (Batch Number: 4301MF017, Expiry: August 2022).The comparator in the ChAdOx1 nCoV-19 prime cohort was Covishield™ [ChAdOx1 nCoV-19 Corona Virus Vaccine (Recombinant), SIIPL] which is a recombinant, replication-deficient chimpanzee adenovirus vector encoding the SARS-CoV-2 Spike glycoprotein. One dose (0.5 mL) contains 5 x 10The comparator used in the BBV152 prime cohort was Covaxin® [Whole Virion Inactivated SARS-CoV-2 Vaccine, Bharat Biotech International Ltd]. Each dose of 0.5 mL contains 6 µg of Whole Virion, Inactivated (SARS-CoV-2) Antigen (strain NIV-2020–770) along with Aluminum Hydroxide Gel, TLR7/8 Agonist and 2-Phenoxyethanol (Batch Number: C10/21004, Expiry: November 2022).All study vaccines (SII-NVX-CoV2373, ChAdOx1 nCoV-19 and BBV152) were administered as a single dose of 0.5 mL intramuscularly in the deltoid.