Use of pritelivir in refractory aciclovir-resistant herpes simplex virus type 2

Recurrence of mucocutaneous herpes simplex virus (HSV) infections is common in immunosuppressed patients. Thymidine kinase mutations conferring resistance to the antiviral agent aciclovir have been observed in such patients. Recommended second-line therapeutic agents against HSV are associated with significant side effects contributing to disease burden. We present a case of aciclovir-resistant herpes simplex virus 2 (HSV-2) in an immunosuppressed (HIV negative) allogenic peripheral blood stem cell transplant (SCT) recipient which was refractory to second-line therapy. Compassionate acquisition of the novel oral helicase-primase inhibitor pritelivir provided both symptomatic and virological control for the duration of its use. We believe this to be the first clinical use of this therapeutic agent in the United Kingdom.