Fig. 2.

Summary of active MERS-CoV vaccine candidates in development. Currently, there are more than a dozen published active vaccine candidates across five general platforms in development for MERS-CoV. To date, all but one of the candidates are in various stages of preclinical development. The DNA-alone candidate has entered Phase I human testing. S: Spike glycoprotein; Fc: crystallizeable fraction of a human antibody; RBD: receptor binding domain of the Spike glycoprotein; Ad5: adenovirus serotype 5; Ad41: adenovirus serotype 41, MVA: modified vaccinia Ankara virus.