A vaccine jointly developed by Pfizer and BioNTech was 90 percent effective

Pfizer says Covid-19 vaccine 90% effective in Phase 3 trial

Covid-19 vaccine from Pfizer and BioNTech is strongly effective, early data from large trial indicate

Protection in patients was achieved seven days after the second of two doses, and 28 days after the first, according to preliminary findings.

 A vaccine jointly developed by Pfizer and BioNTech was 90 percent effective in preventing Covid-19 infections in ongoing Phase 3 trials, the companies announced Monday.

Protection in patients was achieved seven days after the second of two doses, and 28 days after the first, according to preliminary findings.