Serum set to start late-stage human trials for vaccine in a week: ICMR

New Delhi: Serum Institute of India (SII) is expected to begin late-stage human clinical trials of the Oxford Covid-19 vaccine candidate here “within a week” after ethics approvals, Indian Council of Medical Research (ICMR) Director General Dr Balram Bhargava said Tuesday.

Bharat Biotech and Zydus Cadila, which have been conducting early-stage testing of their candidates Covaxin and ZyCov-D over the last 20 days, are also starting second phase trials, he added.

Each stage of a vaccine’s clinical trial tests its safety and ability to develop an effective immune response. While the first phase focusses on safety in healthy participants more, the phase II looks at the effectiveness. The third phase looks into these aspects in a much larger population that would represent a wider demographic.

The SII vaccine, which is to conduct phase II/III clinical trials at around 17 sites, will do so “gradually, as the sites clear their (ethics committee applications),” said Bhargava during a media briefing.

Bharat Biotech has completed its phase I studies for its inactivated virus vaccine candidate at 11 of 12 sites and begun its phase II study, the ICMR DG said. Similarly, Zydus has embarked on the second phase of clinical testing for its DNA plasmid vaccine candidate at 11 sites, Bhargava said, adding “That is also progressing well.”

The Central Drugs Standard Control Organisation late Sunday approved SII’s application to conduct trials of the Oxford candidate, which it has branded ‘Covishield’. SII, the world’s largest vaccine maker, has a tie-up with Swedish-British pharma giant AstraZeneca, that developed the vaccine with the University of Oxford, to manufacture it for low- and middle-income nations. The vaccine is already being tested in South Africa, the UK and Brazil, where participants are being administered two doses nearly a month apart.