India's COVID-19 vaccine candidates will go through a rigorous evaluation process that will not be compromised, the government's Principal Scientific Advisor K Vijay Raghavan said on Friday, indicating that the ICMR-Bharat Biotech vaccine is unlikely to be out by August 15.
Phase 1 of the human trial of any vaccine usually takes 28 days and that is followed by two other phases, Vijay Raghavan said while addressing a webinar at the Vivekananda International Foundation.
India's drug regulator has given the go-ahead for trials for two vaccine candidates -- Bharat Biotech vaccine and the Zydus Cadila vaccine.
"So, the Bharat Biotech vaccine or the Zydus Cadila vaccine will go through a rigorous evaluation process which will not be compromised, as ICMR clarified," Vijay Raghavan said.
Even if the vaccine is available today, it will take one or two years for it to be made available for everyone with priority being given to the vulnerable, he said.
Aiming to launch an indigenous COVID-19 vaccine by August 15, the Indian Council of Medical Research has written to select medical institutions and hospitals to fast-track clinical trial approvals for the vaccine candidate COVAXIN being developed in collaboration with Bharat Biotech.
Responding to a question on ICMR's letter, Vijay Raghvan said, "Today is 10th of the July and let's say the phase 1 trial starts today. And they start at all the 12 sites simultaneously... (which is) unlikely.
"Let us assume that they start together. Phase 1 trial involves an injection, then another injection after seven days and then an examination after 14 days and then looking at the results of that before deciding, so after 28 days"
After Phase 1, there are two other phases, he stressed.
"So the timeline for a vaccine, if we look at the global ones, will go into phase 3 trials in several months after the Phase 1 trial."
Asked how the process can be fastened, Vijay Raghavan said Phases 1 and 2 can be combined and conducted simultaneously. The two phases focus on safety and immunogenicity in humans. Phase 3 also requires a very large number of people over a very long time but that can also be shrunk.
"All this can take can a five to 10-year period which can be brought down to about 12-15-month period. It is an enormously expensive process because a massive parallel processing is required," he said.
Vijay Raghavan added that investing in manufacturing, stock-piling and creating a supply-chain can also be done simultaneously.
Experts have cautioned against rushing into the process for developing a COVID-19 vaccine and stressed that fast-tracking vaccine development for diseases of pandemic potential is not in accordance with globally accepted norms.
Replying to a question on a realistic timeframe for vaccine availability in India, the principal scientific advisor said, "If today there is a vaccine, which can be used...to scale that up for human use requires some time to ramp it up (the production).
"Let's say you have already ramped it up. If you have a few million doses available for everywhere in the world. World organisations will decide the priorities. They will give it to the most vulnerable, then they will give it to the others. So these kinds of vaccines will take a year to roll out. So, availability is spread out over a year or two."
Until then, five things must be diligently followed: face masks; hygiene, handwashing and so on; social distancing, contact tracing; testing and isolation.
"If we do this, we can not only flatten the curve, we can thrash it. This is very tough to do in real life with the economy opening up but we have to focus on that and that should be our job," he said.