 They have antiviral activity that is involved mainly in innate immune response.Two types of IFN-β have been described, IFN-β1 (IFNB1) and IFN-β3 (IFNB3) (a gene designated IFN-β2 is actually IL-6).IFN-β1 is used as a treatment for multiple sclerosis as it reduces the relapse rate.