The adverse event occurred in a 35-year-old participant with no co-morbidities, who was part of Phase 1 trials. The participant was hospitalised with viral pneumonitis, a couple of days after being administered the vaccine
Covaxin, a potential COVID-19 vaccine being developed by Bharat Biotech, reported a serious adverse event during the Phase I clinical trials in August.
However, neither the company nor the regulator, Central Drugs Standard Control Organisation (CDSCO) and its head Drug Controller General of India V.G. Somani, disclosed the matter to the public.
Later, Bharat Biotech Chairman and Managing Director Dr Krishna Ella also confirmed that the adverse event took place and was duly reported to the CDSCO.
Frequently Asked Questions
A vaccine works by mimicking a natural infection. A vaccine not only induces immune response to protect people from any future COVID-19 infection, but also helps quickly build herd immunity to put an end to the pandemic. Herd immunity occurs when a sufficient percentage of a population becomes immune to a disease, making the spread of disease from person to person unlikely. The good news is that SARS-CoV-2 virus has been fairly stable, which increases the viability of a vaccine.
There are broadly four types of vaccine — one, a vaccine based on the whole virus (this could be either inactivated, or an attenuated [weakened] virus vaccine); two, a non-replicating viral vector vaccine that uses a benign virus as vector that carries the antigen of SARS-CoV; three, nucleic-acid vaccines that have genetic material like DNA and RNA of antigens like spike protein given to a person, helping human cells decode genetic material and produce the vaccine; and four, protein subunit vaccine wherein the recombinant proteins of SARS-COV-2 along with an adjuvant (booster) is given as a vaccine.
Vaccine development is a long, complex process. Unlike drugs that are given to people with a diseased, vaccines are given to healthy people and also vulnerable sections such as children, pregnant women and the elderly. So rigorous tests are compulsory. History says that the fastest time it took to develop a vaccine is five years, but it usually takes double or sometimes triple that time.
“The adverse event during phase I clinical trials during August 2020 was reported to the CDSCO-DCGI within 24 hours of its occurrence and confirmation. The adverse event was investigated thoroughly and determined as not vaccine related," LiveMint quoted the company as saying in a statement.
According to The Times of India, the adverse event occurred in a 35-year-old participant with no co-morbidities, who was part of Phase 1 trials at a site in western India. The participant was hospitalised with viral pneumonitis, a couple of days after being administered the vaccine. He was discharged after a week’s stay in the hospital.
Side-effects or adverse effects are largely common in such large studies. However, previously when such incidents occurred, trials were halted. This was the case with the trials undertaken by AstraZeneca and Johnson & Johnson, which only resumed trials after a thorough investigations.
The Hyderabad-based company, in collaboration with the Indian Council of Medical Research (ICMR), has developed Covaxin, a wholly-inactivated novel coronavirus vaccine, which is undergoing three-stage clinical trails.
It entered the third phase of clinical trials on November 16.
The company said it submitted all documentation within timelines, and as mandated by the ethics committees and CDSCO, including a complete causality report, and got an approval for the next two phases of clinical trials only after a detailed investigation of the incident was completed, LiveMint reported.