AstraZeneca announced that results from an interim analysis of clinical trials of AZD1222 in the U.K. and Brazil showed its vaccine with Oxford was “highly effective” in preventing COVID-19, the primary endpoint, and that no hospitalisations or severe cases of the disease were reported in participants receiving the vaccine. There were a total of 131 COVID-19 cases in the interim analysis. One dosing regimen of 2,741 participants showed vaccine efficacy of 90% when AZD1222 was given as a half dose, followed by a full dose at least one month apart, and another dosing regimen of 8,895 participants showed 62% efficacy when given as two full doses at least one month apart. The combined analysis from both dosing regimens resulted in an average efficacy of 70%. All results were statistically significant. “More data will continue to accumulate and additional analysis will be conducted, refining the efficacy reading and establishing the duration of protection,” AstraZeneca said in a statement. 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, it added. No serious safety events related to the vaccine have been confirmed. AZD1222 was well tolerated across both dosing regimens. AstraZeneca 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.