Covid-19: Serum's Covovax gets the nod as a mix-and-match booster shot

Experts say no current vaccine protects against sub-lineages of Omicron

As India's Covid-19 daily case count dips below the 100-mark, approvals for vaccines to be used as a mix-and-match dosing third shot are coming through. After Bharat Biotech's nasal vaccine got the nod as a heterologous booster for the Covishield and Covaxin two-dose primary regimen, it's the turn of Serum Institute of India's Covovax.

The Drugs Controller General of India (DCGI) has approved the market authorisation for SII's Covovax – the Novavax vaccine made in India – as a heterologous booster dose for adults who have been administered two doses of Covishield or Covaxin. In 2022, the DCGI approved Cobevax, Biological E's vaccine, as a heterologous booster after Covishield or Covaxin.

This opens doors for SII to start marketing this vaccine in the private market. SII has a stock of around 20 mn doses of Covishield, the AstraZeneca-Oxford vaccine. It is already producing the Novavax vaccine, branded Covovax for India. Covovax is manufactured through technology transfer from Novavax. It has been approved by the European Medicines Agency for conditional marketing authorisation and has a WHO emergency use listing.

"We are producing the Novavax vaccine; it has been exported so far primarily. We have already exported millions of doses to the US. We have stocks for India as well," said a company source.

It will be interesting to see how SII prices Covovax for India. Bharat Biotech has priced its nasal vaccine iNCOVACC (BBV154) at Rs 800 per dose for the private market and Rs 325 for large-volume government procurement. Corbevax is also priced at Rs 800 per dose.

Demand for vaccines is waning in India, and public health experts are also not in favour of pushing for boosters.

JP Muliyil, an epidemiologist at CMC Vellore and member of the working group of the National Technical Advisory Group (NTAGI), told Business Standard, "None of the existing vaccines can prevent emerging variants of Omicron. These variants target primarily the lining of the upper air passages. Consequently, they induce minor symptoms but are highly infectious. We seem to be in a situation where we can do little, and nothing needs to be done anyway."

As such, demand for vaccines, especially booster shots, has remained low since India has yet to experience a case spike like many other countries. Demand for boosters saw a spike in the first week of January after the China situation escalated.

Public health experts in India belonging to the Indian Public Health Association (IPHA) and the Indian Association of Preventive and Social Medicine (IAPSM) have recently said that it is time to start limiting vaccinations in India (which already has a high coverage) to co-morbid people who have not been naturally infected. 

"With a very high proportion of the population having been exposed to SARS-CoV-2 infection, vaccination against Covid-19 (after recovery from natural infection) will not provide any additional benefits. On the other hand, vaccinations following natural infections may have the potential for some harm, however rare. It would be prudent to err on the side of safety and not insist on vaccination for those who have acquired immunity following natural infection," the report has said.