FDA clears IND application for epigenetic regulator to treat idiopathic neuropathy pain

The FDA has cleared an investigational new drug application for an epigenetic regulator to treat intractable pain due to idiopathic small fiber neuropathy, according to the manufacturer.

The novel regulator, ST-503, will be investigated in a phase 1/2 clinical trial assessing the safety, tolerability and preliminary efficacy of a one-time, intrathecal dose of the treatment, Sangamo Therapeutics announced in a press release. The company additionally said that patient enrollment is expected to begin during the middle of 2025.

According to the release, ST-503 utilizes an adeno-associated virus vector as well as an engineered zinc finger repressor to specifically target a specific gene, SCN9A, that encodes the Nav1.7 sodium channel and is critical for pain signaling. Reduction of these channels’ expression in sensory neurons may, in turn, reduce pain sensitivity in patients.

Idiopathic small fiber neuropathy is estimated to affect at least 43,000 patients in the United States, with peripheral neuropathies in almost 40 million Americans, per statistics cited in the release. Individuals with peripheral neuropathy often experience sensations like burning, prickling, stabbing or pulsing pain.

Currently, there are no long-lasting therapeutic options or cures for the chronic condition.

“The FDA’s clearance of the IND application to evaluate ST-503 in idiopathic small fiber neuropathy represents an important milestone for Sangamo,” Nathalie Dubois-Stringfellow, PhD, chief development officer at Sangamo, stated in the release. “We strongly believe in the power of our zinc finger technology to address neurological conditions and are excited about our plans to advance this program into the clinic next year, to bring hope to patients suffering from debilitating, intractable pain, for which there are insufficient current treatment options.”