After Covishied, Covaxin, and Sputnik V, India is all set to launch the fourth COVID-19 vaccine in the country. India has placed an advance order for 30 crore doses of a new COVID-19 vaccine named Corbevax, from Hyderabad-based company Biological E.
The Hyderabad-based company Biological E, is among the major vaccine makers in India and, by its own claim, is the largest tetanus vaccine producer in the world.
Corbevax has secured permission for the third phase clinical trials of the vaccine and the government is expecting the trials to be over by July. The special thing is that it could potentially be the cheapest vaccine available in India with the two shots expected to be cumulatively priced below Rs 400.
Salient features of the vaccine
The vaccine has received the nod for Phase 3 clinical trials in India after showing promising results in phases 1 and 2.
The Centre will pay Rs 1,500 crore for its consignment of 30 crore doses. Corbevax, like most other COVID-19 jabs out so far, is a two-dose vaccine.
After the completion of the Phase 3 trials, production to meet the Centre's delivery target will continue between August and December.
This builds on the work of the US-based Baylor College of Medicine, which had taken up research on this vaccine after the Sars outbreak of 2002.
Biological-E licensed the technique from the original makers in August.
How Corbevax works
Corbevax is a 'recombinant protein sub-unit' vaccine, which means it is made up of a specific part of SARS-CoV-2 the spike protein on the virus's surface.
The spike protein allows the virus to enter the cells in the body so that it can replicate and cause disease.
However, when this protein alone is given to the body, it is not expected to be harmful as the rest of the virus is absent.
The body is expected to develop an immune response against the injected spike protein.
So when the real virus attempts to infect the body, it will already have an immune response ready that will make it unlikely for the person to fall severely ill.
Novavax has also developed a protein-based vaccine that is still waiting for emergency use authorisation from various regulators.
How Corbevax is different from others
COVID-19 vaccines that are approved so far include mRNA vaccines (Pfizer and Moderna), viral vector vaccines (AstraZeneca-Oxford/Covishield, Johnson & Johnson and Sputnik V) or inactivated vaccines (Covaxin, Sinovac-CoronaVac and Sinopharm's SARS-CoV-2 Vaccine-Vero Cell).
Inactivated vaccines, which include killed particles of the whole SARS-CoV-2 virus, attempt to target the entire structure of the virus.
On the other hand, Corbevax, like the mRNA and viral vector COVID-19 vaccines, targets only the spike protein, but in a different way.
Viral vector and mRNA vaccines use a code to induce our cells to make the spike proteins against which the body have to build immunity.
Like most other COVID-19 vaccines, Corbevax is administered in two doses.
However, as it is made using a low-cost platform, it is also expected to be among the cheapest available in the country.
