A third dose of Pfizer /BioNTech’s COVID-19 vaccine was found to be 86% effective in people aged over 60, an Israeli healthcare provider said on Wednesday, citing initial results from a study of thousands of members.
Israeli HMO Maccabi, which covers around a quarter of the country’s 9.3 million population, compared results from 149,144 people aged over 60 who received their third dose at least a week ago against those from 675,630 more who had received only two doses, between January and February.
Some 37 people tested positive for coronavirus after their third jab, compared with 1,064 positive cases among those who had received only two doses, Maccabi said in a statement. The comparison groups had similar demographic profiles, it added.
Maccabi did not provide any information on the severity of the 37 positive cases, or whether they had any underlying conditions. The Health Maintenance Organisation (HMO) did not immediately respond to a request for comment.
Pfizer has said that its vaccine’s efficacy drops over time, and that a third dose showed significantly higher neutralising antibodies against the initial SARS-CoV-2 virus as well as against the Beta and highly infectious Delta variants.