The study aims to find out how a person fully vaccinated with Covishield or Covaxin responds to a booster of the other vaccine (heterologous vaccination). It will also compare how people react to a third dose of the same vaccine (homologous vaccination).
The institute had presented a clinical trial protocol for the conduct of a phase IV clinical trial for “evaluation of the safety, tolerability and immunogenicity of the Covid vaccines Covaxin and Covishield in a schedule of ‘homologous priming/boost versus a heterologous priming/boost timing in adults from the North Indian region’. , a person in the know told ET.
After detailed deliberations, the Subject Expect Committee (SEC) which advises the Drugs Controller General of India (DCGI) on applications for approval of vaccines, new drugs and clinical trials, at a meeting held early in this week recommended granting permission to conduct the proposed clinical trial project.
The SEC asked the institute to submit a risk mitigation plan for the follow-up study.
India is currently using the same vaccine (primary vaccine) for the precautionary or booster dose, as experts await data on vaccine mixing among the Indian population.
“There is scientific evidence that supports the peer-to-peer vaccine regimen and that is why the government considered it safe to go ahead. The government will consider mixing the vaccines once the data on this will be available,” a senior government official said.
2-3 Institutes carrying out studies | page 6
Two to three medical institutes in the country are conducting studies to assess which regimen works best – homologous or heterologous – but the results are pending.
Christian Medical College (CMC), Vellore, which conducted a study on homologous and heterologous reinforcement, is expected to share its data by the end of this month. The results will determine which booster dose or combination works best.
CMC Vellore has already shared the preliminary results of the study on the feasibility of mixing Covishield and Covaxin – the two main Covid-19 vaccines available in the country.