India to develop its first mRNA vaccine; how it differs from existing COVID vaccines in India

India has approved nine COVID-19 vaccines up until now, of which three - Serum Institute of India's Covishield, Bharat Biotech's Covaxin and Russian vaccine Sputnik V - are being administered in India to people who fit the eligibility criteria.

In October 2021, the country crossed the one billion mark for administered vaccine doses. As of now, about 76 percent of adults have been fully vaccinated, while more than 99 percent have so far received their first dose.

This year, since January 10, India began administering 'precaution dose' to healthcare and frontline workers along with those aged 60 and above.

Now with the Omicron variant in circulation, India is set to launch its first ever 'homegrown' mRNA COVID vaccine, which scientists believe may be effective against the Omicron too. That said, let us find out what makes it different from the other COVID vaccines in use in India.

Also read: Coronavirus: 8 sure-shot symptoms of Omicron; know when you’re likely to get them

Just like all other COVID-19 vaccines, the mRNA vaccine also aims to trigger an immune response by activating cells to fight the deadly pathogens. Traditional vaccines use inactivated or weakened viruses to activate the immune system, while making sure the virus does not replicate.

In case of Messenger Ribonucleic Acid or mRNA based vaccines, the cells are instructed to make a protein or a piece of coronavirus spike protein that produces an immune response in the body. Active immune cells identify this spike protein and in turn create antibodies needed to battle the deadly SARs-COV-2 virus.

That said, an mRNA technology uses a piece of the DNA to convert into an RNA for a cell to be able to produce the spike protein.

Also read: Coronavirus: How long does immunity from booster doses last? Read on what experts have to say

The country's first homegrown mRNA vaccine is being developed by Pune-based Gennova Biopharmaceuticals. As of now, phase 2/3 of the human trials have been completed and the company is in the process of submitting the data to the national regulatory authority.

Phase II and III trials have been completed. We have submitted and presented Phase II data and are in the process of submission of Phase III trial data that was conducted among 4,000 participants,” Dr Sanjay Singh, CEO of Gennova Biopharmaceuticals told a news agency.

Previously, Dr Singh revealed that the vaccine uses a concoction of lipids and enzymes that allows the vaccine to be stored at 2°C to 8°C. It was also highlighted that much of the vaccine manufacturing materials will depend on the imports. Additionally, the officials stated that the Indian mRNA vaccine will be cheaper than their international counterparts or versions (Pfizer BioNTech and Moderna vaccines) but probably costlier than Covishield or Covaxin.

See more: Coronavirus: 2 New BA.2 Omicron Variant Symptoms That Have Come To Light

Unlike mRNA vaccines, Serum Institutes Covishield uses the viral vector platform. It uses a chimpanzee adenovirus – ChAdOx1 – a type of common cold virus, which attaches itself to cells and injects DNA that tells the cells to make coronavirus spike protein. Following the production of spike protein, the immune system detects these invaders and creates antibodies. However, clearing all the myths around this type of vaccine, the US-based Center for Disease Control (CDC) clarifies by saying, "The genetic material delivered by the viral vector does not integrate into a person’s DNA."

Russia-made Sputnik V vaccine, much like Oxford-Astrazeneca (Covishield), uses a weakened version of the common cold adenovirus strain, that seems like coronavirus but doesn't cause illness.

Bharat Biotech's Covaxin is India's first indigenous vaccine against COVID-19. It is developed with Whole-Virion Inactivated Vero Cell-derived technology, which uses a dead virus, incapable of infecting the host cell or replicating, but still able to command the immune system to mount a defensive reaction against an infection.

In the mRNA technology, the cells in the body are instructed to make a protein or a piece of coronavirus spike protein that produces an immune response.

India’s first indigenous DNA vaccine platform, Zydus Cadila’s ZyCoV-D vaccine, was approved for emergency use authorisation in August 2021. It is also the first vaccine approved for use in those aged 12 years and above.

Also known as the third-generation vaccines, DNA-based vaccines use engineered DNA to induce a response against the virus. It is a 'plasmid DNA' vaccine that uses a non-replicating version of a DNA molecule called plasmid, which helps prepare a harmless version of the spike protein present on the SARS-COV-2 membrane.

According to the World Health Organisation (WHO), this "radical new approach" offers several advantages over traditional vaccines, which include "improved vaccine stability, the absence of any infectious agent and the relative ease of large-scale manufacture."