The handful of drugmakers dominating the global coronavirus vaccine race are pushing the boundaries of vaccine technology. The next crop under development feature more conventional, proven designs. FILE PHOTO: Small bottles labelled with “Vaccine” stickers stand near a medical syringe in front of displayed “Coronavirus COVID-19” words in this illustration taken April 10, 2020. REUTERS/Dado Ruvic/Illustration The world will need several different vaccines to fight the COVID-19 pandemic, given the sheer size of global need, variations in effects on different populations, and possible limits of effectiveness in the first crop. Many leading candidates now in final-stage testing are based on new, largely unproven technology platforms designed to produce vaccines at speed. They include messenger RNA (mRNA) technology used by Moderna Inc MRNA.O and Pfizer Inc PFE.N with partner BioNTech SE 22UAy.F , and inactivated cold virus platforms used by Oxford University/AstraZeneca Plc AZN.L , Johnson & […]