Pivotal trial confirms AstraZeneca jab is safe and effective

A big clinical trial conducted in the US, Chile and Peru has provided strong new evidence that the AstraZeneca jab is both safe and highly effective. The findings are the most robust so far to demonstrate that the jab protects adults of all ages.

The AZ vaccine is 79 per cent effective at preventing symptomatic illness and 100 per cent effective at preventing serious illness, hospitalisation or death, according to the study results. The placebo-controlled trial involved more than 32,000 participants across a wide range of ages, of which over 21,000 received two doses of the jab four weeks apart.

Crucially, the trial found no evidence that the vaccine causes blood clots. AstraZeneca has said that an independent safety committee specifically monitored the participants to identify cases of blood clots and found “no increased risk of thrombosis or events characterised by thrombosis” among those who had received the vaccine. Additionally, there were no incidences of cerebral venous sinus thrombosis – a rare blood clot in the brain which has been linked to the AZ vaccine in Germany.

The immensely positive findings will help to repair the jab’s dented reputation; not only because it will quell blood clot fears, but also because it will dispel doubt that European governments have cast on the jab’s efficacy – or lack thereof – in the elderly.

The study was the largest so far to observe the jab’s effects in over 65s. Of the 6,000 over 65s included in the trial, 80 per cent were protected from symptomatic illness, while zero fell seriously ill.

The findings pave the way for the jab’s much-anticipated approval on US soil. AstraZeneca will now submit the trial data to America’s medical regulator, the Food and Drug Administration (FDA). At present, only the Pfizer, Moderna and Johnson & Johnson vaccines have gained FDA approval, but the US has already ordered 300 million doses of the AZ vaccine.

If the AZ jab gains approval as expected, the roll-out is set to begin quickly because the US has supplies at the ready. Around 30 million AZ doses are currently being stored at a facility in Ohio, which handles “fill-finish”- the final stage of the manufacturing process where the vaccine is placed in vials. Facility heads have been awaiting results from the trial as US authorities had insisted on conducting their own study before approving the vaccine for widespread use.

The EU has criticised President Joe Biden for hoarding supplies of a jab that the US has been slow to approve at a time when supplies elsewhere are scarce. Brussels has tried to persuade the US government to hand over some of the doses sitting in storage. Now, the Biden administration seems even less likely to do so.

Yet the EU can at least feel thankful that the study will help to restore confidence in the jab – something which is urgently needed across the continent. According to a new YouGov poll, trust in the AZ jab has dropped significantly in light of the past week’s events; 32 per cent of Germans believe the AZ jab is safe while 55 per cent believe it is unsafe. In France, the numbers are even lower, at 23 per cent and 61 per cent respectively.

The trial – which reiterates the safety and efficacy of the AstraZeneca vaccine – has come at a critical moment.