India's first DNA vaccine against Covid-19 showed 66% efficacy against the disease without any incidence of death or severe illness during clinical trials on 28,000 individuals, its developer Zydus Cadila claimed on Thursday.
The company has applied for Emergency Use Authorization for the vaccine ZyCoV-D from the Central Drug Standard Control Organisation sharing the clinical trial data with the regulator, which would take a call on the EUA approval after scrutinising the information.
As a part of the clinical trial, the indigenous vaccine was tested on 1,000 children of 12-18 years of age. This is the first trial in India on children, who according to some experts may be at greater risk during the third wave in the absence of vaccination, which is now restricted to individuals above 18 years.
While the safety and tolerability data from the kids' trial had been shared with the CDSCO, the company would take at least another four weeks to submit the immune response data to the regulator, said Sharvil Patel, managing director, Cadila Healthcare. The tolerability profile was similar to that seen in the adult population.
During the trial, carried out at 50 sites, the investigators evaluated a two-dose as well as a three-dose regimen of the vaccine. In the first regimen, the vaccines are administered at a gap of 28 days whereas, in the three-dose regimen, the third dose is given 28 days after the second dose.
“In the two-dose regimen, there was no severe case and death whereas, in the three-dose regimen, there was no moderate and severe case. The vaccine efficacy in the two-dose regimen is equivalent to the three-dose one,” he said.
The vaccine – being developed with funding support from the Department of Biotechnology – is one of the vaccines that the Centre plans to procure in its effort to vaccinate 95 crore Indians by December 2021.
The Centre plans to buy five crore doses, which the company hopes to produce once it scales up its production facility to manufacture one crore doses every month by mid-August or September.
Patel claimed since the trials were carried out during the second surge of the epidemic, which was dominated by the Delta variant, it was indirect proof of the homegrown vaccine's efficacy against the variant of concern.
The CDSCO has so far approved four Covid-19 vaccines – Covishield, Covaxin, Sputnik and the one made by Moderna. The Moderna vaccine is yet to reach India as discussions are going between the developer, its Indian partner Cipla and the government on the terms and conditions of bringing the vaccine in India.