Pfizer vaccine is 85% effective after first dose, says Israeli hospital
JERUSALEM (ISRAEL) – A study conducted by a team of healthcare workers at an Israeli hospital has found that the first dose of Pfizer Inc’s COVID-19 vaccine is 85% effective. This fuels a debate over the two-dose schedule as governments are trying to stretch out supplies.
Thes study was conducted at the Sheba Medical Center and it compares with the overall efficacy of around 95% in a two dose regimen having a gap of 21 days for the vaccine developed with Germany’s BioNTech.
The study, which is slated to appear in The Lancet medical journal, comes a day after Canadian researchers hinted that the second Pfizer dose should be delayed as there is a high level of protection from the first shot so that more people can be vaccinated.
Based on an analysis of the documents submitted from its late-stage human trials to the US Food and Drug Administration in December, their research revealed efficacy of 92.6% after the first dose was administered.
In December, the FDA said information from those trials revealed that the vaccine provided some protection to recipients before they got the second shot, adding that more data is necessary to assess the potential of a single-dose shot.
Sheba said among 7,214 hospital employees who got the first shot in January, there was a reduction of 85% in symptomatic COVID-19 within 15 to 28 days. It also said that overall reduction of infections, including asymptomatic cases, was 75%.
Sheba epidemiologist Gili Regev-Yochay warned that the cohort studied at the hospital were “mostly young and healthy”.
Unlike with Pfizer’s clinical trial, “we don’t have many (staff) here aged over 65,” she said, adding that the Sheba study took place during a surge in infections in the country which strained hospitals.