Covaxin, the Covid-19 vaccine developed by Hyderabad-based Bharat Biotech, is “safe, immunogenic with no serious side effects”, according to a study published on Tuesday in medical journal The Lancet.
The report also mentioned that Phase 2 results of Covaxin (codenamed BBV152) do not permit efficacy assessments and further validation with Phase 3 safety results was needed.
“In Phase 2 trial, BBV152 showed better reactogenicity and safety outcomes, and enhanced humoral and cell-mediated immune responses compared with Phase 1 trial. The 6g with Algel-IMDG formulation has been selected for the Phase 3 efficacy trial,” as per the report.
Taking to Twitter, Faheem Younus, Chief of Infectious Diseases at the University of Maryland Upper Chesapeake Health, US, termed the development as “good news”.
Good News: Phase 2 Results of COVAXIN (Bharat Biotech) Published in Lancet380 volunteers studiedDouble-blind, RCT trial2 shots – 28 days apartNo serious (level 4/5) side effectsCan't determine efficacy by phase 2 trials but it's safe/ immunogenic https://t.co/Ef2pdrzZ8c pic.twitter.com/AtXakkJyz6
— Faheem Younus, MD (@FaheemYounus) March 9, 2021
“The evaluation of safety outcomes requires extensive phase 3 clinical trials. We were unable to assess other immune responses (ie, binding antibody and cell-mediated responses) in convalescent serum samples due to the low quantity. Furthermore, no additional data on the age of the participant or the severity of disease from symptomatic individuals were obtained. Comparisons between phase 1 and 2 trials were not done in a randomised set of participants, and no adjustments on baseline parameters were made. Conclusions are to be considered as post-hoc analyses,” the report said.
The Lancet study also mentioned that the study population lacked ethnic, racial, and gender diversity, further underscoring the importance of evaluating BBV152 in other populations.
“This study enrolled a small number of participants aged 12-18 years and 55-65 years. Follow-on studies are required to establish immunogenicity in children and in those aged 65 years and older.”
“Longitudinal follow-up of additional post-vaccination visits (at months 3, 6, and 12) is important for understanding the durability of immune responses, and is ongoing,” it added.
India’s first indigenous Covid-19 vaccine named Covaxin was given approval for emergency use by the Drug Controller General of India (DCGI) before its final stage testing in early January. It had raised concerns about the safety and effectiveness of the vaccine.