Nav1.7 Inhibitors

Partnered Programs – Selective Inhibitors of NaV1.7 for the Treatment of Pain

Based on our discovery of NaV1.7 deficiency underlying the rare human disease called congenital indifference to pain, or CIP, where individuals with CIP are unable to feel pain, we believe that NaV1.7 is a highly-validated target for the treatment of pain.

Chronic pain conditions, such as severe cancer pain and neuropathic pain, are generally recognized as unmet medical needs providing potential commercial opportunities for a new oral pain drug. Currently available pain drugs often have either a lack of meaningful pain relief or dose limiting side effects for many patients. An orally administered selective NaV1.7 inhibitor could present a novel mechanism for the treatment of moderate to severe pain as a single agent or in combination with existing analgesics that work through different mechanisms. We believe that the selective inhibition of NaV1.7 may lower the potential for dose-limiting central nervous system side-effects and allow for an improved side-effect profile for oral administration of such an inhibitor, which could potentially allow for the treatment of pain that has a central or deep tissue component, including cancer pain and neuropathic pain.

Ongoing Collaborations

Flexion Therapeutics acquired the global rights to develop and commercialize XEN402, a Nav1.7 inhibitor also known as funapide. Flexion’s FX301 consists of XEN402 formulated for extended release from a thermosensitive hydrogel. The initial development of FX301 is intended to support administration as a peripheral nerve block for control of post-operative pain. In February 2021, the FDA cleared an IND for FX301, resulting in a $1.0 million milestone payment due to Xenon, and Flexion anticipates initiating a Phase 1b proof-of-concept clinical trial of popliteal fossa block with FX301 in patients undergoing bunionectomy in the first half of 2021. Topline results from that trial could potentially be available in late 2021. Pursuant to the terms of the agreement, Xenon is eligible to receive up to an additional $7.0 million in milestone payments through initiation of a Phase 2 clinical trial.



In December 2011, we entered into a collaborative research and license agreement with Genentech, a member of the Roche Group, to discover and develop selective oral inhibitors of NaV1.7 for the treatment of pain. This ongoing collaboration with Genentech is focused on developing novel inhibitors of NaV1.7 for the treatment of pain.