HYDERABAD:
Covaxin, India’s first indigenous coronavirus
vaccine, has demonstrated nearly 81% efficacy in preventing
Covid-19 after the second dose in those without prior infection, according to its interim Phase 3 trials results made public on Wednesday.
This interim efficacy trend puts Covaxin at par with other global front-runners, the desi vaccine’s co-developer, the Indian Council for Medical Research, said. The results, evaluated by an independent data safety and monitoring board, show that the vaccine is well-tolerated and efficacious across a wide range of age groups and variants, the ICMR added. Covaxin also demonstrates significant immunogenicity against the rapidly emerging variants, said Bharat Biotech CMD Dr Krishna Ella.
According to the Hyderabad-based vaccine maker, the inclusion of the Algel-IMDG adjuvant in the vaccine enhances T-cell immune responses to Covid-19, leading to long-term protection.
The 80.6% efficacy figure was arrived at after 43 cases of Covid-19 were reported among the 25,800 Phase 3 trial participants. While 36 volunteers who received the placebo shot got infected with Covid-19, only seven volunteers that received the two Covaxin shots got infected.
The company said the interim analysis showed that severe, serious, and medically attended adverse events occurred at low levels.
The second interim analysis will be conducted once 87 cases of Covid-19 are reported among the participants and the final analysis will be done once 130 cases are reported.
"The bench-to-bedside journey of the completely indigenous Covid-19 vaccine in less than eight months’ time showcases the immense strength of Atmanirbhar Bharat to fight the odds and stand tall in the global public health community. It is also a testament to India’s emergence as a global vaccine superpower," said ICMR director general Dr Balram Bhargava.
"The development and deployment of Covaxin ensures that India has a powerful weapon in its arsenal in a continually evolving pandemic situation and will go a long way in helping us win the war against Covid-19. The need of the hour is to ensure that people in India continue to receive the vaccine and break the chain of virus transmission," said Dr Samiran Panda, head of epidemiology and communicable disease, ICMR, and director, National AIDS Research Institute.
The volunteers participating in the Phase 3 efficacy study, touted as the largest such study in India so far, are aged between 18 and 98 years. These include 2,433 participants over the age of 60 and 4,500 volunteers with co-morbidities.
The Phase 1 and 2 clinical trials, conducted on 755 participants, demonstrated high safety profile of the candidate vaccine with sero-conversion rates of 98.3% and 81.1% on day 56 and 104, respectively, as per the ICMR.
While the results of Covaxin’s Phase 1 study have been published in Lancet, results of the study on rhesus macaques was published in Nature Medicine on Tuesday.