Data from U.S., Chile and Peru indicates that AstraZeneca/Oxford is safe and 100% effective against severe COVID
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This is a big deal, and in a sign that coverage is improving the most important findings are in the first graf (although, admittedly, not the headline):
The coronavirus vaccine developed by AstraZeneca and the University of Oxford provided strong protection against Covid-19 in a large clinical trial in the United States, offering complete protection against the worst outcomes from the disease while causing no serious side effects, according to data released on Monday.
The findings, announced in a news release from AstraZeneca, may help shore up global confidence in the vaccine. But the fresh data may not make a difference in the United States, where the vaccine is not yet authorized and may not be needed.
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The U.S. trial also recruited participants from Chile and Peru. It found AstraZeneca’s vaccine to be 79 percent efficacious in preventing symptomatic infections. The vaccine was particularly good at preventing severe disease, with 100 percent efficacy in that regard among trial participants who got the vaccine — a major selling point for the shot.
Its overall efficacy was higher than that observed in the vaccine’s previous clinical trials, despite being used on a dosing schedule that may not be optimal. Oxford said that figure could be affected by the thresholds it set for symptomatic Covid-19 cases.
The trial did not turn up any serious side effects, a reassuring sign. European regulators initiated the recent safety review after a small number of people in Europe who had recently been inoculated suffered blood clots and abnormal bleeding.
I wouldn’t say this is making the decision of European regulators to slow down their vaccination efforts and undermine confidence in the vaccine out of fealty to a post hoc ergo propter hoc fallacy look any better.
Anyway, since we’re still weeks away from the vaccine being approved in the US I think the best course of action would be for the US to continue to release more of their AZ stockpile to Canada and Mexico, where AZ is already approved and there are much more serious undersupply problems. But even if most of that American holdings are released in the US and speed up the process here, they will hasten the time when the U.S. has a universally available vaccine and can donate more supplies to other countries.