India close to releasing first COVID-19 vaccine: What are the phases of clinical trial

New Delhi, July 04: ICMR has partnered with Bharat Biotech International Limited (BBIL) for clinical trials of indigenous vaccine 'Covaxin' for the coronavirus.

ICMR said that it is envisaged to launch the vaccine for public health use latest by August 15, after completion of all clinical trials.

Also, another potential COVID-19 vaccine indigenously developed by Ahmedabad-based Zydus Cadila Healthcare Ltd has received approval from Indian regulators to begin human studies.

So what is clinical trial

Clinical trials are a process to test new methods of diagnosing, treating, or preventing health conditions. There are 6 phases of clinical trials.

Phase 0

In phase 0 of a clinical trial, investigators do tests with less number of people, usually fewer than 15. Investigators use a very small dose of medication to make sure the vaccine will not be harmful to humans.

Phase I

Phase I aims to figure out the highest dose humans can take without serious side effects. Investigators spend several months looking at the effects of the medication.

Phase II

Phase II involves more participants, but still not large enough to demonstrate the overall safety of a medication.

They are usually given the same dose that was found to be safe in the previous phase.

Phase III

Phase III usually involves up to 3,000 participants.

To make sure that the medication is at least as safe and effective, investigators use a process called randomization. This involves randomly choosing some participants to receive the new medication and others to receive an existing medication.

Trials in this phase can last for several years.

Phase IV

Phase IV clinical trials happen once the FDA has approved medication. This phase involves thousands of participants and can last for many years.