Pfizer says late-stage coronavirus vaccine study shows moderate side effects

Over 12,000 study participants had received a second dose of the vaccine, Pfizer executives said on an investor conference call. Pfizer said it was continuously scrutinizing the safety and tolerability of the vaccine in its study. The comments follow rival AstraZeneca's COVID-19 vaccine trials being put on hold worldwide on Sept. 6 after a serious side effect was reported in a volunteer in Britain.