Manufacturers Pfizer/BioNTech and Moderna last week said trials of their vaccines showed effectiveness above 90 percent in what was hailed as a breakthrough in stopping the spread of the virus. Pfizer and Moderna last week reported preliminary results from late-stage trials showing their vaccines were nearly 95% effective.
The information from Oxford is derived from 131 total COVID-19 cases (out of 24,000 volunteers) and two separate dosing regimens. The other group of almost 9,000 participants received two full doses a month apart. The 70% figure is an average that masks variation in the performance of two dosing regimens, one of which was found to be 90% effective.
AstraZeneca's vaccine interim analysis data exceeds the 50 percent primary efficacy endpoint set by Indian drug regulator, the Central Drugs Standard Control Organisation (CDSCO), as part of its draft regulatory guidelines for Covid-19 vaccines.
There were no hospitalized or severe cases of Covid-19 reported in the studies.
AstraZeneca is now working on preparing its data for submission to health authorities around the world that have a framework already in place for conditional or early approval of vaccines.
- When will we get the vaccines?
Pollard said that although this was not routine practice in vaccines and added a layer of complexity to its manufacturing, it makes more sense in terms of optimising resource use to guarantee a higher level of protection.
His colleague, Professor Sarah Gilbert, Professor of Vaccinology at the University of Sarah Gilbert, professor of vaccinology at the University of Oxford, said: 'The announcement today takes us another step closer to the time when we can use vaccines to bring an end to the devastation caused by (Covid-19). In parallel, the full analysis of the interim results is being submitted for publication in a peer-reviewed journal. This will be a key factor in determining the global reach of these vaccines.
The vaccine's cost to governments works out at just a few dollars a shot, a fraction of the price of shots from Pfizer and Moderna, which use a more unconventional technology. AstraZeneca is yet to share late-phase safety and tolerability data but said no serious safety events related to the vaccine have been confirmed. That should make the vaccine click in India.
In poor countries, where the logistics of distributing rival vaccines posed a bigger challenge, the effect of a cheaper and easier alternative could be even more pronounced. However, with a small tweak in dosages, it seems to be about 90 per cent effective in preventing COVID-19. If FDA authorization is granted shortly after an advisory committee meeting scheduled for December 10, the first vaccines could be available to health care workers by the end of the year.