The world’s first DNA vaccine against Covid-19, made by Zydus Cadila, received an emergency use authorisation for use on children and adults from the Indian regulator on Friday, clearing the decks for its commercial rollout.
While the homegrown vaccine is the first Covid-19 shot approved for 12-18-year-olds, it is not immediately clear whether the shot’s initial roll out will include the adolescents as a target group. But eventually it would be administered to them.
Developed by Zydus Cadila with support from the Department of Biotechnology, the three-dose intradermal vaccine, ZyCoV-D, showed a primary efficacy of 66.6% for symptomatic RT-PCR positive cases in phase-III clinical trials over 28,000 volunteers.
“With this approval, India now has its first Covid-19 vaccine for the adolescents in the 12-18 age group, besides the adult population,” the company said in a statement.
“It is a matter of great pride that on Friday we have the EUA for the world’s first DNA Covid-19 vaccine by Zydus developed in partnership with the DBT. This is an important milestone in our indigenous vaccine development mission and positions India on the global map for novel vaccine development," said Renu Swarup, Secretary, DBT.
The plus points of a DNA vaccine, explains eminent scientist Shahid Jameel, is that it is easy to manufacture and the process can be automated since DNA is a far more stable molecule than RNA. Also such vaccines have better temperature stability.
The minus points are generally less immunogenicity than proteins (and now RNA) and intradermal delivery of such vaccines. For this Zydus uses a very good needle free technology. Also ZyCod-D needs three doses and it would be logistically difficult to ensure compliance.
“But overall it's a useful vaccine to have, especially with its approval for 12-18 year olds. This comes as good news as schools open,” Jameel, director of the Trivedi School of Biosciences at Ashoka University told DH.
ZyCoV-D will be administered using a needle-free applicator known as PharmaJet, which ensures painless intradermal vaccine delivery. The shots will be given on first-28th-and 56th day. The company plans to manufacture 10-12 crore doses of the vaccine every year.
In a statement, Pankaj Patel, chairman of the Zydus Group said, “This is a historic milestone with ZyCoV-D, a product of Indian innovation becoming the world’s first DNA vaccine being offered for human use and supporting the world’s largest immunisation drive. We are particularly happy that our vaccine will enable the country to vaccinate a larger population especially in the age group of 12-18 years.”
Before the Zydus vaccine, the CDSCO approved five Covid-19 vaccines – Covishield, Covaxin, Sputnik, Moderna and the single shot vaccine of Johnson and Johnson. The last two are yet to be launched commercially in India.
The DNA platform used in the Zydus vaccine provides ease of manufacturing with minimal biosafety requirements. Another of its advantages is to allow generating new constructs quickly to deal with mutations in the virus, such as those already occurring.
The company plans to seek approval for the two dose regimen of the vaccine, on which the CDSCO sought more data.