Verdinexor (KPT-335) is a small-molecule selective inhibitor of nuclear export (SINE). Karyopharm Therapeutics has recently developed first-in-class, novel SINE compounds using molecular modeling to screen a small virtual library of compounds against the NES groove of human exportin-1 (XPO1). These compounds inhibit nuclear-cytoplasmic export by reversibly binding to the cargo recognition site of XPO1 and are orally bioavailable. Verdinexor was shown to potently and selectively inhibit vRNP export and effectively inhibited the replication of various influenza virus A and B strains in vitro, including pandemic H1N1 virus, highly pathogenic H5N1 avian influenza virus, and the recently emerged H7N9 strain. Verdinexor is in development for the treatment of viral indications. Verdinexor is being evaluated for the treatment of lymphomas in pet dogs with newly-diagnosed or first relapse after chemotherapy lymphomas.