Following a clinical trial in the US, British-Swedish drugmaker AstraZeneca on Wednesday revised down the efficacy figure for its two-dose COVID vaccine.

The company now says its vaccine is 76% effective rather than 79% effective at preventing any kind of symptomatic Covid. 

An independent panel of experts appointed to supervise the trial said AstraZeneca failed to include updated data after the company announced the first figure.

AstraZeneca, under fire for its complications regarding its vaccine, stood by its assessment of the results of its US trials, saying it would publish new data “within 48 hours”.

Earlier on Tuesday, a US government agency raised concerns that AstraZeneca may have used outdated drug data information provided during US trials for its COVID-19 vaccine.

Although AstraZeneca vaccine is cheaper and easier to store than many of its rivals, several countries in Europe and other parts of the world last week suspended its use because of isolated cases of blood clots.