A leading coronavirus vaccine candidate developed by Pfizer and BioNTech will be submitted for regulatory approval “within days,” the companies announced Wednesday, after their final analysis suggested the drug was even more effective than previously thought.

The U.S. pharma giant and its German partner said their Phase 3 trial was now complete and that it found the vaccine was 95 percent effective at preventing symptomatic Covid-19 — up from the 90 percent announced last week.

There have been no serious side effects among the 41,135 adults who received two doses, the companies said in a joint statement. The most common reactions were that 3.7 percent of participants experiencing fatigue and 2 percent had a headache, it said.