Bharat Biotech gets go-ahead to conduct Phase-III trials of Covaxin

The around 28,500 people expected to enrol for the Phase-III trials would be given two doses of the investigational vaccine

With Hyderabad-based Bharat Biotech receiving an approval to conduct Phase-III trials for Covaxin, India inches closer to having its own vaccine to fight the coronavirus pandemic. This is crucial as the government plans to start vaccinating the healthcare and essential workers starting January.

The Subject Expert Committee (SEC) at Central Drugs Standard Control Organisation (CDSCO) which is reviewing proposals related to Covid-19 drugs and vaccines has granted permission to the vaccine maker to start Phase-III trials after it assessed data from the Phase-I and II trials along with the animal challenge study.

"In continuation of the SEC meeting dated 05.10.2020, the firm presented their data from Phase-I and II along with animal challenge data in two species including NHP on the Inactivated Coronavirus Vaccine (BBV152) along with the proposal to conduct event-driven Phase-III clinical trial to assess the efficacy of the vaccine," the expert panel said.

The SEC, however, has also noted that this approval is conditional, subject to the primary efficacy endpoint for symptomatic cases being amended. It has recommended that once a suspect case was confirmed, it would be evaluated to be classified as a symptomatic case. Either an RT-PCR test confirmation or, if the subject shows symptoms like shortness of breath or difficulty in breathing, it should be present to classify a case as confirmed symptomatic.

According to sources, around 28,500 people are expected to enroll for the Phase-III trials who will be given two doses of the investigational vaccine. The preliminary results of Covaxin trials have shown promising results (including immunogenicity) and not many side effects.

The SEC had asked for the safety and immunogenicity data from the ongoing Phase-II trials.

Bharat Biotech had halved the size of the Phase-II clinical trial of Covaxin to only 380 volunteers after it got good immunogenicity data from the Phase-I. Volunteers did not complain of any major side effects apart from fever and body aches. 

The trial size for Phase-I and II trials was set at 1,125 candidates. Of this, 375 volunteers were vaccinated in Phase-I. So, 750 were to be a part of the Phase-II studies. For Phase-II studies, Bharat Biotech tested the vaccine on children above 12 years of age.

The firm had got the nod from the Drug Controller General of India to conduct Phase-I and II trials in July.