New Delhi: For those of you who don’t know, India has placed an advance order to block 30 crore doses of a new Covid-19 vaccine called, Corbevax, from Hyderabad-based company Biological E. In fact, it also could potentially be the cheapest vaccine available in India when it finally launches. Yes, you heard us right! Scroll down for more details. Also Read - Novavax Covid Vaccine, to be Made by Serum Institute, 90% Effective, Protects Against Variants

Corbevax COVID Vaccine: How is it different from Covishield, Covaxin or Other Vaccines? All You Need to Know

Covid Vaccine (Representational image)

Let’s first find out how Corbevax works. Also Read - Single Dose of COVID-19 Vaccine Sufficient For Those Already Infected, Says Study

How does Corbevax work?

Corbevax, a recombinant protein sub-unit vaccine, has shown promising results in Phase 1 and 2 trials. It is made up of a specific part of SARS-CoV-2 — the spike protein on the virus’s surface. Also Read - Explained: Why Some People Don't Get Fever After Vaccination And is That Harmful?

Here’s how the vaccine works. Basically, the spike protein allows the virus to enter the cells in the body so that it can replicate and cause disease thus developing an immune response against the injected spike protein. However, please note that since this protein alone is given to the body, it is not expected to be harmful as the rest of the virus is absent.

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. For the uninitiated, this method is in place since decades to make hepatitis B vaccines, but Corbevax will be among the first Covid-19 vaccines to use this platform. Meanwhile Novavax has also developed a protein-based vaccine, which is still waiting for emergency use authorisation from various regulators.

How is Corbevax different from Covishield, Covaxin or Other COVID vaccines?

Currently, COVID 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).

So, how is Corbevax different from any of these? Basically, inactivated vaccines include killed particles of the whole SARS-CoV-2 virus and they attempt to target the entire structure of the virus. However, 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. “In this case (Corbevax), we’re actually giving the protein,” IE quoted Dr Peter Hotez, Professor and Dean at Baylor College of Medicine’s National School of Tropical Medicine.

Although Corbevax is indigenously produced, its beginnings can be traced to the Baylor College of Medicine’s National School of Tropical Medicine. The School had been working on recombinant protein vaccines for coronaviruses SARS and MERS for a decade.

Corbevax is administered in two doses. Also interestingly, it is also expected to be among the cheapest vaccines available in the country as it is made using a low-cost platform.

According to the reports, the vaccine is reportedly going to be the cheapest vaccine available in India with the two shots expected to be cumulatively priced below Rs 400. In comparison, the Covishield vaccine comes at Rs 300-Rs 400 for a single dose. The Russian Sputik V, the third vaccine that has received emergency approval for use in India, costs around Rs 1,000.

How soon will Corbevax COVID vaccine be available in India?

As per the reports, the vaccine has received the nod for Phase III clinical trials in India after showing promising results in phases I and II. The central government will pay Rs 1,500 crore for its consignment of 30 crore doses. Corbevax, like most other Covid-19 vaccines, is a two-dose vaccine. After the completion of the Phase III trials, production to meet the Centre’s delivery target will continue between August and December.

Will Corbevax be a game changer?

Importantly, this is the first time the central government has placed an order for a vaccine that has not received emergency use authorisation and has payed Rs 1,500 crore in advance to block an order that could vaccinate 15 crore Indian citizens. The Centre has provided major pre-clinical and clinical trial support towards the vaccine’s development, including a grant-in-aid of Rs 100 crore from the Department of Biotechnology.

About Biological E, the manufacturer of Corbevax

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. It has seven WHO-prequalified shots, including a five-in-one vaccine against diphtheria, tetanus, pertussis, hepatitis B and haemophilus influenza type-b infections. Its vaccines are supplied to over 100 countries and it has supplied more than two billion doses in the last decade.