Whereas clinical studies have suggested improvements in some outcomes for patients treated with recombinant IFN in viral myocarditis (159–162), recombinant IFN therapy is not part of usual viral myocarditis management, with somewhat disappointing trial results attributed possibly to a relatively poor response to IFN of parvovirus B1 and HHV6 myocarditis (163). This evidence concerns the gene IFNA1 and myocarditis.