Trial boost for AstraZeneca vaccine
ASTRAZENECA’S Covid-19 vaccine performed better than expected in a major late-stage trial potentially paving the way for its emergency authorisation in the US and bolstering confidence in the shot after setbacks in Europe.
The drugmaker said yesterday that trials in Chile, Peru and the US found the vaccine, developed with Oxford University, was 79% effective in preventing symptomatic Covid-19 and, crucially, posed no increased risk of blood clots. It intends to request US emergency authorisation next month.
More than a dozen European countries, including Germany and France, had halted use of the AstraZeneca vaccine earlier this month after some reports linked it to blood clots in a very small number of people. They have since resumed inoculation after a regional regulator said it was safe, but an opinion poll yesterday showed Europeans remained sceptical over its safety.
Hailed as a milestone in the fight against the Covid-19 pandemic when it first emerged as a vaccine contender last year, the AstraZeneca shot has since been dogged by confusion over its efficacy, dosing regimen and possible side-effects as well as supply setbacks in Europe, where the company has been at the centre of a growing conflict between Brussels and London over so-called “vaccine nationalism”.
The latest data should help address some of those concerns, analysts said. Based on more than 32 000 people, the trial was larger and elderly volunteers featured more prominently than in previous trial results from the UK which had prompted some European countries to initially hold back using the AstraZeneca shot on older people.
US trials of rival vaccines from Pfizer and Moderna, which are already being deployed in the US have showed efficacy rates of around 95%.
But the AstraZeneca vaccine, which is already widely used outside the US, is seen as crucial to tackling the spread of Covid-19 across the globe because it is easier and cheaper to transport than rival shots. The vaccine has been granted a conditional marketing authorisation or emergency use in more than 50 countries but it has yet to be approved in the US, where President Joe Biden is stepping up US response to the pandemic by expanding testing, ramping up vaccinations and boosting production.