HSV gene transfer in the treatment of chronic pain.

It has proven difficult to use systemic administration of small molecules to selectively modulate nociception. Over the past decade, we and others have developed non-replicating herpes simplex virus (HSV)-based vectors to treat chronic pain. Subcutaneous inoculation of an HSV vector effectively transduces sensory neurons in the dorsal root ganglion; release of transgene-coded inhibitory neurotransmitters or anti-inflammatory peptides reduces pain-related behaviors in rodent models of chronic inflammatory and neuropathic pain. A phase 1 trial of this therapy in patients is set to begin soon.