By Graham Lawton
A health worker in Turkey holds a syringe during the phase III trial of the coronavirus vaccine candidate developed by Pfizer and BioNTecht. (Photo by Dogukan Keskinkilic/Anadolu Agency via Getty Images)
Dogukan Keskinkilic/Anadolu Agen
US drug maker Pfizer and its German partner BioNTech have today released some positive-looking results from a clinical trial of their experimental covid-19 vaccine BNT162b2.
The headline figure is 90 per cent effective. But that may not be quite as good news as it first appears.
What did Pfizer and BioNTech find?
The results are from a phase III clinical trial, the final stage of …