Serum-free production of rVSV-ZEBOV in Vero cells: microcarrier bioreactor versus scale-X™ hydro fixed-bed.

•Serum-free rVSV-ZEBOV production in adherent Vero cells was investigated to optimize critical process parameters.•Production at 34 °C showed higher infectious viral titers than at 37 °C resulting in 8.79 × 107 TCID50/ mL at 36 hpi.•Ratios of the viral genome copy number (VG/mL by droplet PCR) to the infectious viral titer were used to assess the product quality.•The optimized bioprocess was scaled-up and evaluated in a microcarrier bioreactor as well as a novel fixed-bed bioreactor.