Two positive developments this week could potentially expand access to the Pfizer-BioNTech COVID-19 vaccine at a time when nations around the world are trying to ramp up vaccinations.
A study in Israel showed that the vaccine is robustly effective after the first shot, echoing what other research has shown for the AstraZeneca vaccine and raising the possibility that regulators in some countries could authorize delaying a second dose instead of giving both on the strict schedule of three weeks apart as tested in clinical trials.
Although regulators in the United States have held fast to the requirement that people receive two doses of the Pfizer-BioNTech vaccine three weeks apart, the British government decided to prioritize giving as many people as possible an initial dose, allowing delays of up to 12 weeks before the second dose. The Israeli study could bolster arguments for emulating that approach in other countries.