Zydus Cadila on Thursday, July 1, announced that it sent an application for emergency use authorization (EUA) to the Drugs Controller General of India (DCGI) for its COVID-19 vaccine called ZyCoV-D. In a filing with the stock exchange, the company said the interim analysis has shown that the vaccine, a plasmid DNA vaccine, has a primary efficacy of 66.6%. ZyCoV-D is a three-dose, intradermal vaccine, and is stored at 2-8ºC. It has shown good stability at temperatures of 25ºC for at least three months as well, the company said. The thermostability of the vaccine will help in easy transportation and storage of the vaccine and reduce any cold chain breakdown challenges leading to vaccine wastage, the company added.
A plasmid DNA vaccine is one that, when injected, produces the spike protein of the SARS-CoV-2 virus and elicits an immune response mediated by the cellular and humoral arms of the human immune system, which play a vital role in protection from disease as well as viral clearance. The Plasmid DNA platform also allows generating new constructs quickly to deal with mutations in the virus, such as those already occurring.
Zydus said that it has completed one of the largest clinical trials in India for the vaccine across 50 centres. The company also said that the vaccine has been tested on the adolescent population of the 12-18 age group. Around 1,000 subjects were enrolled in this age group and the vaccine was found to be safe and very well tolerated, the company said.
The company has said that in its clinical trials, no moderate case of COVID-19 disease was observed in the vaccine arm post administration of the third dose, suggesting 100% efficacy for moderate disease. No severe cases or deaths due to COVID-19 occurred in the vaccine arm after administration of the second dose of the vaccine.
Since it is a plasmid DNA vaccine, ZyCoV-D doesn’t have any problem associated with vector-based immunity, Zydus added. Dr Sharvil Patel, Managing Director, Cadila Healthcare Ltd, said, “As the first-ever plasmid DNA vaccine for human use, ZyCoV-D has proven its safety and efficacy profile in our fight against COVID-19. The vaccine when approved will help not only adults but also adolescents in the 12 to 18 years age group.”
The company said that it has also evaluated a two-dose regimen for the ZyCoV-D vaccine, using a 3 mg dose per visit, and the immunogenicity results had been found to be equivalent to the current three-dose regimen. “This will further help in reducing the full course duration of vaccination while maintaining the high safety profile of the vaccine in the future,” the company said.
If Zydus Cadila’s vaccine gets DCGI approval it will be the fifth vaccine to get emergency use approval in India. A few days ago, Moderna’s COVID-19 vaccine was approved by India and Indian pharmaceutical company Cipla will be in charge of procuring the vaccines. Currently, three other vaccines — Serum Institute of India’s Covishield, Bharat Biotech’s Covaxin and Russia’s Sputnik V — are being administered across India.