AstraZeneca’s Revised US Trial Result Shows 76% Efficacy

AstraZeneca releases revised trial results after the accuracy of the initial results were questioned.

(Image Courtesy: IANS)

Publishing revised results of the US Phases 3 trials, AstraZeneca says its COVID vaccine has 76% efficacy in preventing symptomatic illness, reported Reuters.

This new result – which is slightly lower than the earlier published 79% – comes after health experts in the US publicly called out the initial trial results.

On Monday, 22 March, the company released interim data for Phase 3 clinical trial of its COVID-19 vaccine in countries including USA and Chile.

Amidst emerging reports of the vaccine causing blood clotting in beneficiaries, countries in EU started banning the AstraZeneca vaccine. It was hoped that this data would clear doubts about the efficacy and safety of the vaccine.

US federal health officials, however, rebuked the results of AstraZeneca’s vaccine trial, criticising them for using 'outdated information'.

In light of the backlash, AstraZeneca agreed to release a new analysis of the US trial based on more extensive data, reported IANS.

While the earlier interim data was based on 141 infections, the latest data was based on 190 infections among more than 32,400 participants in the United States, Chile, and Peru.

AstraZeneca reiterated on Thursday, 25 March, that their vaccine was 100% effective against severe or critical forms of the disease. It also said the vaccine showed 85% efficacy in adults 65 years and older.

On the basis of the new results, AstraZeneca reportedly plans on seeking US emergency use authorisation soon.

In spite of the controversy surrounding the vaccine, WHO continues to back the AstraZeneca vaccine saying the ‘benefits outweighed the risks’.

(Written with inputs from Reuters and IANS)

(The article was first published in FIT and has been republished with permission.)