Positive high-level results from an interim analysis of clinical trials in the United Kingdom and Brazil of a COVID-19 vaccine candidate from Astra Zeneca showed that the vaccine was highly effective in preventing COVID-19, the primary endpoint, and no hospitalizations or severe cases of the disease were reported in participants receiving the vaccine, according to a press release from Astra Zeneca.
The vaccine, AZD1222, which was developed at the University of Oxford and licensed to Astra Zeneca, is the third vaccine candidate to report promising interim results from Phase 3 clinical trials. The other vaccine candidates are from Moderna and Pfizer and BioNTech.
There were a total of 131 COVID-19 cases in the interim analysis for AZD1222.
One dosing regimen (n=2,741) showed vaccine efficacy of 90 percent when AZD1222 was given as a half dose, followed by a full dose at least one month apart, and another dosing regimen (n=8,895) showed 62 percent efficacy when given as two full doses at least one month apart. The combined analysis from both dosing regimens (n=11,636) resulted in an average efficacy of 70 percent. All results were statistically significant.
The pooled analysis included data from the COV002 Phase II/III trial in the United Kingdom and COV003 Phase III trial in Brazil. Over 23,000 participants are being assessed following two doses of either a half-dose/full-dose regimen or a regimen of two full doses of AZD1222 or a comparator, meningococcal conjugate vaccine called MenACWY or saline. The global trials are evaluating participants aged 18 years or older from diverse racial and geographic groups who are healthy or have stable underlying medical conditions.
An independent Data Safety Monitoring Board determined that the analysis met its primary endpoint showing protection from COVID-19 occurring 14 days or more after receiving two doses of the vaccine. No serious safety events related to the vaccine have been confirmed. AZD1222 was well tolerated across both dosing regimens.
AstraZeneca said it will now immediately prepare regulatory submission of the data to authorities around the world that have a framework in place for conditional or early approval. The company will seek an Emergency Use Listing from the World Health Organization for an accelerated pathway to vaccine availability in low-income countries. In parallel, the full analysis of the interim results is being submitted for publication in a peer-reviewed journal.
The Astra Zeneca vaccine has an added benefit: It can be stored, transported and handled at normal refrigerated conditions (2-8 degrees Celsius/ 36-46 degrees Fahrenheit) for at least six months and administered within existing healthcare settings.
Pascal Soriot, Chief Executive Officer of Astra Zeneca, said: “Today marks an important milestone in our fight against the pandemic. This vaccine’s efficacy and safety confirm that it will be highly effective against COVID-19 and will have an immediate impact on this public health emergency.”
Clinical trials are also being conducted in the US, Japan, Russia, South Africa, Kenya and Latin America with planned trials in other European and Asian countries. In total, the Company expects to enroll up to 60,000 participants globally.
The company said it has manufacturing capacity of up to 3 billion doses of the vaccine in 2021 on a rolling basis, pending regulatory approval.
