The emerging biotech Gritstone Bio (NSDQ:GRTS) has dosed the first patient with its second-generation COVID-19 vaccine known as GRT-R910. The University of Manchester and Manchester University NHS Foundation Trust are jointly overseeing the U.K.-based Phase 1 study. The GRT-R910 vaccine uses self-amplifying mRNA (SAM), which could optimize antigen expression at lower doses relative to conventional…