Novartis AG / Spinifex Pharmaceuticals, Inc.

Peripheral Neuropathic Pain (Postherpetic Neuralgia and Painful Diabetic Neuropathy)

Disease Overview

Peripheral neuropathic pain is chronic pain caused by damage to peripheral nerves from diabetes, viral infection (herpes zoster), cancer treatment, or trauma. It is poorly served by existing first- and second-line therapies (gabapentinoids, TCAs, SNRIs, topical lidocaine/capsaicin), with high failure rates and central nervous system side effects that limit dosing in older patients.

Competitive Landscape

The neuropathic pain landscape has been dominated for two decades by Pfizer's Lyrica (pregabalin) and generic gabapentin, both gabapentinoids approved for PHN, alongside off-label SNRIs (duloxetine), tricyclic antidepressants, and topical agents (lidocaine 5%, capsaicin 8% patch / Qutenza). All centrally acting agents carry sedation, dizziness, and cognitive side effects that limit dosing, particularly in elderly PHN patients. EMA401 was positioned to be the first-in-class peripheral AT2R antagonist that worked outside the blood-brain barrier, avoiding CNS side effects. Phase 2 PHN data published in The Lancet showed efficacy with no observed CNS adverse events, which drove Novartis's $200M-upfront acquisition of Spinifex in June 2015 (with up to ~$500M in clinical and regulatory milestones for ~$700M total). However, Novartis subsequently halted both Phase 2b PHN and PDN trials after liver toxicity emerged in chronic preclinical studies, ending EMA401's program. The discontinuation left the peripheral mechanism category without an advanced candidate; subsequent novel approaches in neuropathic pain have shifted toward Nav1.7/Nav1.8 selective sodium channel blockers (Vertex's VX-548 / suzetrigine).