NEW DELHI: The centre has approved Biological E’s Corbevax as a precaution dose for those above 18 years who have been fully vaccinated with either Covishield or Covaxin, officials announced Wednesday.
“Corbevax will be available as a precaution dose after completion of six months or 26 weeks from administering the second dose of either Covaxin or Covishield vaccines for population above 18 years. This enables Corbevax as a heterologous Covid-19 vaccine for precaution dose administration in this age group,” Union Health Secretary Rajesh Bhushan said in a letter to all the states and union territories.
This is the first time a booster dose different from the one used for primary vaccination against Covid has been allowed in India.
Bhushan said there would be no change in existing guidelines for homologous precaution dose administration of the Covaxin and Covishield vaccine. “In addition to the existing homologous precaution dose, the option of a heterologous precaution dose with Corbevax would be available to all persons above 18 years of age,” the letter issued on August 8 but issued on Wednesday, said.
The Union Health Ministry approved it based on the recommendations recently made by the Covid-19 Working Group of the National Technical Advisory Group on Immunisation (NTAGI).
Bhushan said that based on scientific evidence, global practices and the recommendations of domain knowledge experts, it has now been decided to redefine the precaution dose administration under the Covid-19 vaccination programme.
India's first indigenously developed RBD protein subunit vaccine Corbevax, manufactured by a Hyderabad-based firm, is currently being used to inoculate children in the age group of 12 to 14 years under the Covid-19 immunisation programme.
At present, the same Covid-19 vaccine which has been used for administration of first and second doses is being given as a precaution dose to all above 18 years.
All necessary changes regarding the administration of the precaution dose of the Corbevax vaccine to those who are eligible and due to the precaution dose have been made on the Co-WIN portal. This provision would be live from August 12, Bhushan added.
In its July 20 meeting, the Covid-19 Working Group (CWG) reviewed data of the double-blind, randomised phase-3 clinical study, which evaluated the immunogenicity and safety of a booster dose of Corbevax vaccine when administered to Covid-19-negative adult volunteers of age 18-80 years previously vaccinated with two doses of either Covishield or Covaxin.
“Following the examination of the data, the CWG observed that the Corbevax vaccine can induce a significant increase in antibody titers when given to those who have received either Covaxin or Covishield, likely to be protected as per the neutralisation data also,” official sources added.
On June 4, the Drugs Controller General of India (DCGI) approved Corbevax as a precaution dose for those above 18 years.
About 97 percent of the above 12 years in the country has been covered with at least one dose, and about 89 percent of the same age group has been covered with a second dose.
Currently, five Covid-19 vaccines are being used under the vaccination programme - Covishield, Covovax, Covaxin, Sputnik V vaccine and Corbevax.
India began administering precaution doses of vaccines to healthcare and frontline workers and those above 60 years with comorbidity from January 10.
From March 16, India began inoculating children aged 12-14 years, and the government also removed the comorbidity clause for those above 60 years for the precaution doses.
On April 10, India began administering free precaution doses to all aged above 18 years.