The head of British drug manufacturer AstraZeneca said further research was needed on its Covid-19 vaccine after questions emerged over the protection it offers, but the additional testing is unlikely to affect regulatory approval in Europe.
AstraZeneca and its partner, the University of Oxford, announced on Monday that it was seeking regulatory approval for the vaccine after it showed an average 70% effectiveness.
That rate jumped to 90% when an initial half-dose then a full dose was given, similar to that of rival vaccines in development by Pfizer/BioNTech and Moderna.
But it emerged the higher rate of effectiveness came during tests in people aged 55 and under, and was discovered by accident during the clinical trials.
The head of the Oxford Vaccine Group, Andrew Pollard, said this week that further evidence will be available next month, but the result was still “highly significant”.
“Now that we’ve found what looks like a better efficacy, we have to validate this, so we need to do an additional study,” AstraZeneca chief executive Pascal Soriot told Bloomberg.
He said he expected there would be another “international study but this one could be faster because we know the efficacy is high, so we need a smaller number of patients”.
The additional trial was not likely to delay regulatory approval in Britain and the EU, Soriot said.
There are high hopes for the AstraZeneca/Oxford vaccine, which Pollard has hailed as a “vaccine for the world” given that it could be cheaper to make, and easier to store and distribute.
It can be stored, transported and handled at normal refrigerated conditions of between two and eight degrees Celsius (36-46 Fahrenheit) for at least six months.
Pfizer/BioNTech’s offering requires temperatures of -70C, driving up costs and potentially making it out of reach for lower and middle-income countries.
AstraZeneca/Oxford has also promised to provide its vaccine to the developing world on a non-profit basis.
