Covaxin trials begin on 375 volunteers across 12 hospitals

As part of the double-blind clinical trials, both vaccine and placebo will be given to volunteers

The vaccine has been developed by Bharat Biotech in collaboration with Indian Council of Medical Research (ICMR) and the National Institute of Virology (NIV). Photo: iStock

The first phase of human trials for Covaxin, the COVID-19 vaccine candidate developed by Bharat Biotech International Limited has started on 375 individuals.

According to sources at SRM Medical College Hospital and Research Centre, Chennai, the trials have begun in 12 centres identified by Indian Council of Medical Research (ICMR), across the country. SRM Hospital is one of the 12 testing centres.

In some centres, healthy volunteers are being identified and screened before they are administered the drug, while in others the screening is likely to start from Monday (July 20).


With the overall tests planned to be conducted on 1,200 volunteers, 375 volunteers will be administered the drug in the first phase. The rest will be tested in the second phase.

The first phase is likely to be completed in 45 days, making it highly unlikely for the ICMR to launch the vaccine by its ambitious deadline of August 15.

The data would be analysed and appropriate corrections and adjustments would be made before moving on to the second phase.

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Since Phase 1 and Phase 2 are being combined to speed up the process, the tests for the second phase would start without waiting for the results of the first phase as that would take a longer time. Scientists and physicians would be constantly monitoring the volunteers of Phase 1 to ensure that they do not face any serious side-effects.

As part of the double-blind clinical trials (where neither participants nor researchers know who is receiving which treatment), both vaccine and placebo are given to volunteers.  In this kind of trial, both the volunteers and the researcher will get to know about the result only after the test period is over.

The ICMR on July 3 had announced that India’s first indigenous vaccine is being planned to be launched by August 15, much to the surprise of the scientific community as none of the manufacturers developing 145 vaccines across the world have set any timeline for the same.

The vaccine developed by Bharat Biotech in collaboration with ICMR and the National Institute of Virology (NIV) was developed by isolating the SARS-CoV-2 strain in NIV and transferring it to Bharat Biotech.

The volunteers include both male and female in the age group of 18-55 who are being enrolled after a thorough medical check-up. While pregnant women are excluded from the trials, only medically fit individuals will be deemed right for the trials.

The selected volunteers would be tested periodically and their blood samples taken. The data and samples including the personal details of volunteers would be collected as per protocol, kept confidential and sent to BBIL.

Related news: My jaw dropped with disbelief: Scientist on Aug 15 launch of Covaxin

While in normal clinical trials, the first phase takes between six and 18 months, and is followed by a second and third phase where the vaccine is administered on a larger number of people, the test has been fast-tracked in this case with the ICMR deciding to club phases one and two together. After the two phases, if a majority of candidates do not report any problems and results turn out to be good, the government may allow the vaccine to be manufactured.

Meanwhile, the testing process would continue through its normal course of 194 days for the first phase while the other tests would be conducted over a minimum period of two years.

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