The US Food and Drug Administration (FDA) is likely to approve the Pfizer/BioNTech vaccine any day now and yesterday published a document detailing data from the phase 3 trial. The 53-page report shows in graphs and tables that the vaccine works well across sex, age, and co-morbidities groups.
One particular graph that had people excited shows how quickly and how consistently the vaccine provides meaningful protection. The data shows that about two weeks after the first dose, the vaccine is effective and that the protection does not wane for at least two months. More long-term effectiveness will be estimated as more data is collected.
It is crucial in phase 3 trials to track when people become infected with the disease, both in the control group and in the vaccinated cohort. With this data, researchers work out the efficacy of the vaccine. For the Pfizer/BioNTech vaccine (BNT162b2) efficacy is 95 percent. And, as we see in the graph below, it shows the staggering difference in the number of cases between a vaccinated population and an unvaccinated one.
The data also shows that the most common side effect is pain and redness for a week after the injection which was experienced by about 80 percent of the vaccine recipients. One percent of all the vaccinated people describe it as severe. Interestingly, people over 55 are less likely to find it painful.
The Pfizer/BioNTech vaccine was approved by the UK regulatory agency last week, and vaccinations in the British Isles began yesterday. The first two people to be vaccinated were 90-year-old Margaret Keenan and 81-year-old William Shakespeare (not the Bard).