The coronavirus vaccine developed by Oxford university and AstraZeneca has exceeded regulatory requirements for effectiveness in phase 3 trials, giving another boost to hopes that the disease can be defeated.
The vaccine will be submitted for approval “immediately” after Oxford and AstraZeneca said two different dosing regimens showed different levels of effectiveness in trials in the UK and Brazil.
When the vaccine was given as a half dose, followed by a full one at least one month later, efficacy — a measure of how a vaccine prevents infection or severe disease in trials — was 90 per cent. When the jab was given as two full doses at least one month apart, efficacy was 62 per cent. The average efficacy was 70 per cent.
The results were better than the 50 per cent efficacy sought by both the US Food and Drug Administration and the European Medicines Agency.
Andrew Pollard, chief investigator of the trial at Oxford, said: “These findings show that we have an effective vaccine that will save many lives.”
The difference in efficacy between the two Oxford vaccine doses was unexpected. The scientists speculate that the lower first dose may have primed the immune system in a way that made it more receptive to the second jab, but more research will be needed to confirm this.
The Oxford-AstraZeneca jab became the great hope of British science and during the summer was regarded worldwide as the leader in the Covid-19 vaccine race, as its clinical trials proceeded first in the UK and then across the world. AstraZeneca planned to enrol up to 60,000 trial participants globally, more than any other vaccine candidate.
But Oxford fell behind Moderna and Pfizer/BioNTech when its trial was halted following the illness of one participant — an adverse event that was not said to be caused by the vaccine. In the UK and Brazil, the trial resumed after a few days but in the US the delay lasted several weeks; US trial data were not included in the interim analysis published on Monday.
Matt Hancock, the UK’s health secretary, said vaccinations could start next month, with the bulk of the rollout taking place after January, subject to regulatory approval. The UK has secured 100m doses of the jab.
Better than expected results from Pfizer/BioNTech and Moderna — showing efficacy close to 95 per cent — spurred widespread optimism and market rallies, though their vaccines are sold at profit, and much of their projected supply for next year has been secured by richer nations. By contrast, AstraZeneca, along with Johnson & Johnson, has said it will sell its inoculation at cost to the world during the pandemic. J&J trials are ongoing.
The jab is priced at about $3 to $4 a dose, supply deals suggest, a fraction of the price of other vaccines. AstraZeneca has agreed to sell it at cost to developing nations in perpetuity. The vaccine can be stored long-term at normal fridge temperature, between 2C and 8C. Others require a storage temperature as low as -70C. AstraZeneca is targeting the manufacture of up to 3bn doses next year. Depending on regulatory approval, different dosing regimens could mean more doses are available.
“This vaccine is more suitable for rollout in poorer countries because it only requires refrigeration,” said Ellen ‘t Hoen, the director of Medicines Law & Policy, a research group. “They had the foresight to work with vaccine producers in developing countries early on [such as India’s Serum Institute] and those producers will be able to provide the vaccine as soon as the regulators give the green light.”
AstraZeneca has received approximately 3.2bn orders of its jab, data by Airfinity shows.
Suerie Moon, the co-director of the Global Health Centre at Geneva’s Graduate Institute, said a key trait of the vaccine was that it was “funded, developed and licensed with global access as a central objective”.
Prof Pollard told a news briefing on Monday morning: “We have a vaccine for the world.”
Additional reporting by Harry Dempsey in London
https://news.google.com/__i/rss/rd/articles/CBMiP2h0dHBzOi8vd3d3LmZ0LmNvbS9jb250ZW50LzJkYTk3YTU2LTIzZGYtNDM0NS05MTU3LTZkYzhlYzMyMmM2OdIBP2h0dHBzOi8vYW1wLmZ0LmNvbS9jb250ZW50LzJkYTk3YTU2LTIzZGYtNDM0NS05MTU3LTZkYzhlYzMyMmM2OQ?oc=5
2020-11-23 07:42:00Z
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