Covid-19 vaccine: Real-world data to decide commercial marketing approval

The drug regulator may consider real-world data from the ongoing Covid-19 vaccinations to grant faster commercial marketing approval to the vaccine candidates, according to sources in the know.
 
Commercial nod would mean that the manufacturer can sell it in the private market with a specified maximum retail price. Vaccines are typically sold through hospitals or paediatricians for administering doses to infants or young children.  Vaccine makers are now not allowed to commercially sell it as they have been granted ‘restricted emergency-use’ approval, which allows them to sell only to the Indian government which, in turn, distributes the vaccines.
 
Two such vaccines are Covishield, made by the Serum Institute of India (SII), and Covaxin by Bharat Biotech. India has vaccinated 100 million with these two vaccines. Around 91 million have received Covishield, developed by AstraZeneca and Oxford University. Nearly 8.7 million have got Covaxin, according to the CoWIN dashboard.
 
“This is sufficient data to show how the vaccine works in individuals, whether it generates the desired immune response, protects against severe disease, and causes any serious adverse event. Marketing authorisation (allowing private sales) thus, can be granted based on this real-world data,” said a senior government official.
 
Commercial approval in this way, based on the real-world data that is available, will probably be a faster process than through the traditional route in that the analysis of the data from clinical trials could be faster.

 
Typically, from the laboratory to the market, vaccine development takes years. During the pandemic, the entire process from pre-clinical trials to the emergency-use authorisation has taken around a year.
 
Phase 2 clinical studies involving over 1,000 people assess the immunogenicity of a vaccine. Phase 3 clinical studies, conducted over a few thousand people and over a period of time, assess the efficacy.
 
The data is analysed once there are a good number of disease cases in the sample. This helps to analyse if vaccinated or placebo receivers had contracted the disease. The Covid-19 pandemic has accelerated this process as many people are being infected with the disease. So ‘unblinding’ the data to assess a vaccine’s efficacy is taking a shorter time.
 
“Vaccine makers have been submitting documents right from the beginning and there has been a rolling review of the process by the regulator. This does not happen otherwise. It is due to the emergency, thanks to the pandemic, that this process of review was accelerated and real-time,” said another senior official at the Central Drugs Standard Control Organisation. SII is likely to apply for commercial marketing nod by the end of April for Covishield.
 
It has been submitting data to the drug regulator from the international trials conducted by AstraZeneca, as well as data from Indian bridging trials and the ongoing vaccinations. Vaccine makers have been submitting data on adverse events periodically with the drug regulator.
 
They would also need to compile the data on immune responses and RT-PCR-positive Covid cases, as well as hospitalisation events from those who have already been vaccinated.
 
Senior government officials, however, pointed out that a ‘rushed’ commercial approval may create a demand-supply mismatch.