The first of four experimental COVID-19 vaccines being tested by Pfizer and its German partner BioNTech showed encouraging results in very early testing of 45 people, the companies announce.
Study volunteers given either a low or medium dose, in two shots about a month apart, had immune responses in the range expected to be protective, when compared to some COVID-19 survivors, according to the preliminary results.
Side effects are typical for vaccines, mostly pain at the injection site and fever.
The report has been submitted for publication in a scientific journal but not yet reviewed. With its other potential candidates still in the earliest stage of testing, Pfizer aims to open a large-scale study this summer but can’t yet say which shot is best to include.
About 15 different COVID-19 vaccine candidates are in human testing worldwide, with several poised to begin huge, last-stage studies to prove if they really work.