To broaden the trials, age limit and eligibility criteria will be relaxed to include diverse volunteers and also healthcare workers
The third phase of human trials of India’s COVID-19 vaccine ‘Covaxin’ are set to begin at the Indian Institute of Medical Sciences (IMS) and SUM Hospital in Odisha.
The Central Drugs Control Organisation (CDSCO) has given approval for third phase trials of Covaxin, Dr E Venkata Rao, Principal Investigator in the Covaxin human trial and Professor in the Department of Community Medicine at IMS and SUM Hospital told Mint.
Covaxin is being indigenously developed by the Indian Council for Medical Research (ICMR) and Bharat Biotech. IMS and SUM Hospital is the only institute from Odisha on the ICMR’s list of 21 medical institutes where trials are underway.
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.
"After completion of the first and second phase of the trial with demonstrable safety profile and immunogenicity, the large scale efficacy trial involving thousands of volunteers has been planned now," Dr Rao added.
To broaden the trials, age limit and eligibility criteria will be relaxed to include diverse volunteers and also healthcare workers. Response has been enthusiastic and huge, he noted.
Half of the volunteers will received placebo (as per practise) and will be under observation for “a considerable period of time to look at the efficacy of the vaccine,” he added.
Those interested in volunteering for the trial can register at www.ptctu.soa.ac under the section register for clinical trials, Dr Rao said.Follow our full COVID-19 coverage here