Pritelivir mesylate is active against herpes simplex virus types 1 and 2 (IC50: 0.02 μM against HSV1-2). Pritelivir mesylate is an inhibitor of the viral helicase-primase complex. Pritelivir mesylate shows antiviral activity in vitro and in animal models of herpes simplex virus (HSV) infection.

HSV1-2:0.02 μM

Pritelivir mesylate is the first in a class of antiviral agents that inhibit HSV replication by targeting the viral helicase–primase enzyme complex. Pritelivir mesylate has potent and resistance-breaking antiviral efficacy with potential for the treatment of potentially life-threatening HSV type 1 and 2 infections, including herpes simplex encephalitis. Pritelivir mesylate (0.03-45 mg/kg) significantly increases survival. Pritelivir mesylate (0.3-30 mg/kg) reduces mortality against HSV-1, E-377. Combination therapies of Pritelivir mesylate at 0.1 or 0.3 mg/kg/dose with Acyclovir (10 mg/kg/dose) are protective when compared to the vehicle treated group against HSV-2, strain MS [2][3].