WHO grants India's Covaxin jab emergency approval
Thursday November 04 2021
A health worker inoculates prepares a dose of the Covaxin vaccine against the Covid-19 coronavirus at a health centre in New Delhi on October 21, 2021. PHOTO | AFP
The World Health Organisation (WHO) Wednesday granted emergency authorization to Covaxin, the first coronavirus vaccine developed in India.
This makes Covaxin developed by Bharat Biotech, Indian multinational biotechnology company the eighth Covid-19 vaccine to be approved, adding to a growing portfolio of vaccines validated by WHO for the prevention of Covid-19 caused by Sars-CoV-2.
Since Covid-19 was declared a public health emergency of international concern (PHEIC) in January 2020, the UN health agency has given the green light to Pfizer-BioNTech, Moderna, Oxford-AstraZeneca, Johnson&Johnson, Sinopharm (Beijing), Serum Institute of India: Covishield (Oxford/AstraZeneca), and Sinovac: CoronaVac.
The WHO said in a tweet that Covaxin met standards for protection against Covid-19 and that the benefit of the vaccine far outweighs the risks.
Covaxin has a 78 per cent efficacy rate against Covid-19 and should be administered in two doses, with a dose interval of four weeks, in all age groups 18 and above.
The approval also notes that Covaxin had 78 per cent efficacy against Covid 19 of any severity, 14 or more days after the second dose, and is extremely suitable for low- and middle-income countries due to easy storage requirements.
“Available data on vaccination of pregnant women with the vaccine are insufficient to assess vaccine safety or efficacy in pregnancy; studies in pregnant women are planned, including a pregnancy sub-study and a pregnancy registry,” the WHO said in a statement.
WHO’s emergency use listing (EUL) is a prerequisite for Covax Facility an initiative aimed at equitable access to vaccines directed by Gavi, the vaccine alliance, the coalition for epidemic preparedness innovations (Cepi), and the WHO.
WHO’s EUL procedure assesses the quality, safety, and efficacy of Covid-19 vaccines and is a prerequisite for Covax vaccine supply. It also allows countries to expedite their own regulatory approval to import and administer Covid-19 vaccines, says WHO.
The assessment is performed by the product evaluation group, composed of regulatory experts from around the world and a technical advisory group (Tag), in charge of performing the risk-benefit assessment for an independent recommendation on whether a vaccine can be listed for emergency use and, if so, under which conditions.
“This emergency use listing expands the availability of vaccines, the most effective medical tools we have to end the pandemic,” said Dr Mariângela Simão, WHO assistant-director general for access to medicines and health products. “But we must keep up the pressure to meet the needs of all populations, giving priority to the at-risk groups who are still waiting for their first dose, before we can start declaring victory.”
On Wednesday, India’s top drug regulatory authority said that it was extending the shelf life of Covaxin from six to 12 months from the date of manufacture, based on data showing that it is safe and effective.
A Phase 3 study involving 25,800 participants in India aged 18 to 98 found that Covaxin had an efficacy of 93.4 per cent against severe Covid-19 disease and overall vaccine efficacy of 77.8 per cent against symptomatic infections confirmed by PCR tests. Against asymptomatic Covid-19, the efficacy was 63.6 per cent. The vaccine also conferred 65.2 per cent protection against symptomatic infection with the Delta variant, at least two weeks after the second dose.
The main side effects from Covaxin were pain at the injection site, followed by headache, fatigue, and fever. No severe or life-threatening adverse events were reported. The vaccine works by teaching the immune system to make antibodies against the Sars-CoV-2 coronavirus. The antibodies attach to viral proteins, such as the so-called spike proteins that stud its surface.
To create Covaxin, Bharat Biotech used a sample of the coronavirus isolated by India’s national institute of virology. They then doused the coronaviruses with a chemical called beta-propiolactone before disabling them by bonding to their genes rendering the virus inactivate.
The researchers then drew off the inactivated viruses and mixed them with a tiny amount of an aluminum-based compound called an adjuvant (Adjuvants stimulate the immune system to boost its response to a vaccine). Because the coronaviruses in Covaxin are dead, they can be injected into the arm without causing Covid-19. Once inside the body, some of the inactivated viruses are swallowed up by a type of immune cell called an antigen-presenting cell.