Oxford-AstraZeneca COVID-19 vaccine granted emergency use authorization in multiple countries
The approval in India, widely reported at the start of the week, is an important milestone, said AstraZeneca, as it will enable supply in India but also in a large number of countries around the world.
The pharma company has partnered with the Serum Institute of India (SII), which is a leading vaccine manufacturer, for the supply of the vaccine to the Indian government but also to a large number of low and middle-income countries.
On December 30, the UK authorized emergency supply of the vaccine, now called COVID-19 Vaccine AstraZeneca, but formerly referenced as AZD1222, for those 18 years and older; the move represented the first authorization received for the drug. People in the UK started receiving that vaccine on Monday [January 4].
AstraZeneca has also submitted a substantial data package to support a conditional marketing authorization for its COVID-19 vaccine to the European Medicines Agency (EMA), as part of an ongoing rolling review process; it said it continues to work closely with that EU agency on the authorization request.
In addition, the pharma group is seeking Emergency Use Listing from the World Health Organization (WHO) for an accelerated pathway to vaccine availability in low-income countries during this health crisis and has ongoing rolling reviews with many other regulatory authorities around the world.
Pascal Soriot, CEO, AstraZeneca, said: “These emergency use authorizations will soon bring the vaccine to many millions of people and are proof of our long-held commitment to broad and equitable access around the world. We hope this effective, well-tolerated and simple-to-administer vaccine will now begin to have a real impact on this deadly virus."
Manufacturing capacity
AstraZeneca is aiming for global manufacturing capacity of up to 3 billion doses of the vaccine in 2021 (around three times that of Pfizer or Moderna, who are aiming for 1.3 billion and 1 billion respectively).
Its vaccine can be stored, transported and handled at normal refrigerated conditions for at least six months and administered within existing healthcare settings.
The vaccine was co-invented by the University of Oxford and its spin-out company, Vaccitech. It uses a replication-deficient chimpanzee viral vector based on a weakened version of a common cold virus (adenovirus) that causes infections in chimpanzees and contains the genetic material of the SARS-CoV-2 virus spike protein. After vaccination, the surface spike protein is produced, priming the immune system to attack the SARS-CoV-2 virus if it later infects the body.
Efficacy trials
COVID-19 Vaccine AstraZeneca was shown in clinical trials to be safe and effective at preventing symptomatic COVID-19, with no severe cases and no hospitalizations more than 14 days after the second dose.
The interim analysis for efficacy was based on 11,636 participants accruing 131 symptomatic infections from the UK and Brazil Phase III trials conducted by Oxford University.
As published in The Lancet on 8 December 2020, the primary efficacy endpoint based on a pooled analysis showed that the vaccine was 70.4% (confidence interval: 54.8% to 80.6%) effective at preventing symptomatic COVID-19 occurring more than 14 days after receiving two doses of the vaccine.
A secondary efficacy endpoint of prevention of severe disease demonstrated no cases of severe infections or hospitalizations in the vaccine group.
The safety data published so far is from over 20,000 participants enrolled across four clinical trials in the UK and Brazil and South Africa.
The Lancet publication confirmed that AZD1222 was well tolerated and that there were no serious safety events confirmed related to the vaccine. The participants were from diverse racial and geographic groups who are healthy or have stable underlying medical conditions. This analysis provides safety data on 74,341 person-months of follow-up after first dose (median 3.4 months) and 29,060 person-months of follow-up after two doses (median 2.0 months).
The overall reported rates of serious adverse events were 0.7% in the vaccine group and 0.8% in the control group.
In addition to University of Oxford-led trials, the company is conducting a large trial in the US as part of a global program. In total, the University of Oxford and AstraZeneca expect to enroll more than 60,000 participants worldwide. Additional safety and efficacy data will continue to accumulate from ongoing clinical trials, it said.
