UK, which approved the Oxford University-AstraZeneca Covid-19 vaccine Covishield on Wednesday, has rebuffed the vaccine maker’s claims that a half dose followed by a full dose of the vaccine offers more protection against the coronavirus. The statement by UK health officials has raised more concerns about the efficacy of the vaccine especially since no data has been published yet to verify the fresh claims.
The Oxford-AstraZeneca vaccine has been a centre of controversy since the time drugmakers claimed that a half dose followed by a full dose was more efficient in preventing the infection than two full doses. Th data had showed that the vaccine was able to achieve 90% efficacy after administration of half dose followed by full dose as opposed to two full doses which achieved 62% efficacy.
Munir Pirmohamed, chair of a British advisory group on COVID-19 vaccines has said that the claim made by the drugmaker about 90% efficacy after altering the dosage regimen does not hold up under analysis. Pirmohamed said a higher success rate could have been achieved due to a longer gap between the administration of the first and second shots of Covishield vaccine.
Earlier, the vaccine was approved by the UK government following recommendation by the Medicines and Healthcare Regulatory Agency (MHRA). Expressing his delight at the development AstraZeneca CEO Pascal Soriot said it was significant in fight against Covid-19. The approval to Covishield was granted in the UK following rigorous clinical trials and a thorough analysis of the data. MHRA has said the vaccine has been able to adhere to the standards set up by it for safety, quality and effectiveness.
India might soon become the second country to green light the vaccine. Last week, Serum Institute of India had submitted additional data on the safety and efficacy of the vaccine following Drug Controller General of India’s demand early this month.