This comes in light of a recent study by the Christian Medical College (CMC) Vellore, which showed that a booster dose of Covishield after primary vaccination with Covaxin gives 6 to 10 times higher antibody levels.
However, similar results for not observed when Covaxin was given as a booster after two Covishield doses.
According to PTI, the Covid Working Group of NTAGI has reviewed the findings of the study.
"Considering programmatic challenges the matter would now be discussed in the NTAGI standing technical sub-committee meeting for a final recommendation," a source was quoted as saying.
As of now, mixing of Covid-19 vaccines is not allowed in the country, which means the precaution dose is of the same vaccine as the first and second doses.
Biological E seeks Corbevax approval as booster
This comes after Hyderabad-based Biological E on 4 May submitted an application to India's drug regulator, seeking emergency use authorisation for its Covid-19 vaccine Corbevax as a booster dose for adults who have been given two doses of either Covishield or Covaxin.
According to the EUA application submitted to DCGI, Biological E in a phase-3 placebo-controlled clinical study has evaluated the safety and immunogenicity of Corbevax as a single-dose booster in Covid-negative adults vaccinated with Covishield or Covaxin.
The company conducted the study on 416 subjects aged 18 to 80 who took the second jab at least six months ago.
"The results showed a significant boost in immunogenicity in terms of neutralizing antibodies after 28 days when compared with placebo cohort in both Covishield and Covaxin arms. The safety profile of Corbevax was found similar to that of the earlier clinical trials," PTI quoted a source from the firm as saying.
“We are now submitting the marketing authorization application for grant of permission Corbevax for restricted use in an emergency situation as a booster dose at six months after completion of primary immunization with two doses of Covishield or Covaxin in individuals aged 18 years and above," it added.
India's booster dose programme
India began administering precaution doses of Covid vaccines to healthcare and frontline workers and those aged 60 and above with comorbidities from 10 January.
The comorbidity clause was removed in March, making all people aged above 60 years eligible for the precaution dose of Covid vaccine.
On 10 April, the country began administering precaution doses of Covid-19 vaccines to all aged above 18 years at private vaccination centres.
All those above the age of 18 who have completed nine months after the administration of the second dose are eligible for the precaution dose.
The nine-month norm has been relaxed for citizens travelling overseas, as the Centre allowed them to get the shot before the stipulated waiting period as required by the guidelines of the destination country.
With inputs from agencies.
