Pfizer and BioNTech are teaming up on a coronavirus vaccine. Photo: Drew Angerer/Getty Images
Patients who received an experimental coronavirus vaccine being developed by Pfizer and BioNTech generated immune responses to the virus, and there were no life-threatening side effects, according to early trial results posted Wednesday and reported by STAT.
The big picture: This particular vaccine is still a long ways away from proving it works and getting federal approval, but it's an encouraging first step that the vaccine appears to trigger an immune system response and is mostly safe.
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