The government on Wednesday approved Biological E's Corbevax as a precaution dose for those above 18 years fully vaccinated with either Covishield or Covaxin.
This is for the first time that a booster dose that is different from the one used for primary vaccination against Covid has been allowed in the country.
The concept of heterologous booster dose implies the use of a different vaccine from what was used for a primary dose. While under the homologous booster vaccine concept, a person is injected the same vaccine that was used for the previous doses.
"This provision would be live from August 12," Union Health Secretary Rajesh Bhushan said in a letter to states and Union territories.
He said that Corbevax will be available as precaution dose after completion of 6 months or 26 weeks from the date of administration of the second dose of either Covaxin or Covishield vaccines for population above 18 years.
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"This enables use of Corbevax as a heterologous COVID-19 vaccine for precaution dose administration in this age group," Bhushan said.
There will be no change in existing guidelines for homologous precaution dose administration of Covaxin and Covishield, he said.
The decision has been taken based on scientific evidence, global practices and the recommendations of domain knowledge experts.
India's COVID-19 vaccination program has achieved the historical milestone of administering more than 2 billion doses so far.
About 97 per cent of the 12 plus age population of the country has been covered with at least one dose and about 89 per cent with both doses.