Zydus Cadila, the Ahmedabad-headquartered pharmaceutical company, has approached India’s top drug regulator for restricted emergency approval for  ZyCov-D, its three-dose Covid-19 vaccine. If approved for use, this would be the world’s first DNA vaccine against Covid-19. The vaccine was tested in late-stage human clinical trials involving over 28,000 participants. It has been found to have a primary efficacy of 66.6 per cent so far, this means it was able to bring down symptomatic cases of Covid-19 in those who received the vaccine by nearly 67 per cent compared with those who did not receive a vaccine. Even though this efficacy is lower than that of most other Covid-19 vaccines approved in India, the strength of  ZyCov-D lies in its effectiveness against the Delta variant of the virus, Zydus Cadila managing director Dr Sharvil Patel said. Zydus Cadila has also tested ZyCoV-D’s safety and ability to prompt an immune response in a trial involving 1,000 adolescents between the ages of 12 and 18 years. However, it is unclear at this stage whether the company is pushing for approval for this age group. The vaccine, which is in its second phase of trials, is a “plasmid DNA” vaccine that can be stored at 2-8 degree Celsius. Watch the video to know everything.