mRNA vaccines for seasonal flu could be a $6b market in a best case scenario Seasonal flu vaccines were a c.$5b market in 2020 for the major manufacturers (GSK, Sanofi, CSL, AZN). With efficacy typically sub 60% there is room for improvement and given proof of concept for mRNA with COVID-19, interest is growing in possible use in flu. PFE/BNTX, SAN/TBIO and MRNA are all starting trials in 2021 with early data possible by end of year. We think efficacy will need to be very good as there are potentially substantial cost of goods issues. Experts we have spoken to ballpark single antigen mRNA vaccine costs at c$10-15/dose, scaling for additional antigens; some quadrivalent (4-antigen) non-mRNA products can sell for as little as $14 now. If efficacy is attractive, we estimate the market for mRNA flu vaccines could be c.$6b (best case) with no preference yet for existing manufacturers v newcomers given almost no data.