Zydus Cadila on Thursday announced that the company has applied for emergency use authorisation (EUA) to the Drugs Controller General of India (DCGI) for ZyCoV-D -- its needle-free plasmid DNA vaccine against Covid-19. If approved, it will become the world's first DNA vaccine against Covid.ZyCoV-D is a three-dose, intradermal vaccine, and is needle-free, also leading to a significant reduction in any kind of side effects. Interim analysis has shown it to be 66.6 per cent effective for symptomatic RT-PCR positive cases.If regulators consent, ZyCoV-D could become the second home-grown shot, after Bharat Biotech's Covaxin; and fourth to get a DCGI nod for use against the viral infection in India after Covishield, Covaxin and Sputnik V."This breakthrough marks a key milestone in scientific innovation and advancement in technology. 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," said Dr Sharvil Patel, Managing Director, Cadila Healthcare, in a statement."The vaccine, when approved, will help not only adults but also adolescents in the 12 to 18 years age group," he added.ZyCoV-D is a plasmid DNA vaccine which 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 Covid-19 vaccine was also tested in the adolescent population in the 12-18 years age group in India and was found to be safe and very well tolerated.ZyCoV-D had already exhibited a robust immunogenicity and tolerability and safety profile in the adaptive Phase I/II clinical trials carried out earlier. Both the Phase I/II and Phase III clinical trials have been monitored by an independent Data Safety Monitoring Board.The vaccine is stored at 2-8 degrees Celsius but has shown good stability at temperatures of 25 degrees Celsius for at least three months. 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 has said.The plasmid DNA platform also provides ease of manufacturing with minimal biosafety requirements (BSL-1). The Plasmid DNA platform also allows generating new constructs quickly to deal with mutations in the virus, such as those already occurring.The company has also evaluated a two-dose regimen for 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.