AstraZeneca seeks further Covid vaccine trial after questions raised

27 Nov 2020

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AstraZeneca will look to put the Covid-19 vaccine candidate developed with the University of Oxford through further testing.

AstraZeneca has said that regulatory approval of the Covid-19 vaccine it is developing with the University of Oxford won’t be delayed, despite it calling for more testing.

The company said on 23 November that an interim analysis of its clinical trials in the UK and Brazil showed an effectiveness of 90pc when volunteers received a smaller dose of the vaccine followed by a standard second dose.

However, Bloomberg has reported that AstraZeneca is now looking to perform another global trial of the vaccine candidate to confirm this 90pc efficacy rate, separate from another study analysing the vaccine currently underway in the US.

Questions surrounding the study’s results were raised after AstraZeneca said that a manufacturing discrepancy resulted in a lower dosage of the vaccine appearing more effective than it was.

As neither AstraZeneca or the University of Oxford quickly disclosed this error data, concerns were raised about transparency in the trial. There were also concerns that the low-dose trial didn’t include anyone over the age of 55.

Seeking US approval

After the matter was raised earlier this week, Mene Pangalos, AstraZeneca’s executive vice-president for biopharmaceuticals research and development, said the mistake is “actually irrelevant”.

“Whichever way you cut the data – even if you only believe the full-dose data … we still have efficacy that meets the thresholds for approval with a vaccine that’s over 60pc effective,” he said.

Speaking more recently with Bloomberg, AstraZeneca CEO Pascal Soriot said: “Now that we’ve found what looks like a better efficacy we have to validate this, so we need to do an additional study.” He added that this additional trial will be faster to complete because researchers know the efficacy is high, meaning fewer patients are required.

Soriot said the biggest concern for the company and the University of Oxford is getting US regulatory approval due to trials being conducted outside the US and the fact questions have now been raised about the trial data.

“The question for us was, will we need the US data to get approval in the US or can we get approval in the US with international data, and it was never clear,” he said. “Now with those results, it’s more likely that we will need the US data.”

Colm Gorey was a senior journalist with Silicon Republic