The National Advisory Committee on Immunization (NACI) is reversing a recommendation it made March 1, and now says there’s enough ”real-world evidence” to show the AstraZeneca COVID-19 vaccine’s safe and effective for seniors.

NACI chair Dr. Caroline Quach says two studies of patients who received the shot in the U.K. released since then, show AstraZeneca’s both safe and effective for seniors; especially against severe disease and hospitalization.

Dr. Quach adds if there’s a choice, the vaccines from Pfizer and Moderna should be prioritized for use on seniors.

Several European countries have also reversed a recommendation against using AstraZeneca on seniors, including France, Germany and Italy, while Sweden’s the latest to join a growing group of European countries choosing to temporarily suspend its use.

The European Medicines Agency says there’s no indication the AstraZeneca vaccine’s causing blood clots, and is convinced its benefits outweigh the risks.

The agency says it’ll make a recommendation Thursday.