Sorrento Therapeutics Gets FDA Go-Ahead for Cancer Pain Clinical Trial

The FDA has authorized Sorrento Therapeutics’ Investigational New Drug Application (IND) for their chronic pain drug candidate, Resiniferatoxin (RTX). The biopharmaceutical company plans to start a multicenter Phase Ib clinical trial to test assess the injectable drug’s safety and efficacy in treating intractable cancer pain.

“Given its unique mechanism of action, we view RTX as a franchise molecule, uniquely positioned to halt the neurogenic inflammation cycle in a number of clinical indications,” said Dr. Henry Ji, President and Chief Executive Officer of Sorrento Therapeutics, Inc. “Our intention is to commence our clinical path in cancer since more than 80% of cancer patients experience uncontrolled pain during their disease and 20% of these patients remain unresponsive or intolerant to mainstay, opioid therapy.”

RTX is a non-opioid, TRPV1 agonist that targets afferent nerves, which are activated in patients with chronic pain. The biologic was previously given Orphan Drug Status by the FDA for the treatment of patients with end-stage cancer pain.

“We are confident in RTX providing meaningful relief to these patients given previous pre-clinical and clinical findings demonstrating that a single injection of RTX could safely and effectively reduce severe pain as well as the use of concomitant analgesics,” said Ji.

A Phase I clinical trial of RTX is currently underway, and 12 terminal cancer patients have been treated with the drug. The study – conducted at the National Institutes of Health (NIH) – has already provided evidence that the drug is well tolerated and reduces pain while reducing opioid-dependence.

Preclinical studies have shown that the receptor agonist does not affect touch or muscle function. The researchers have not observed any systemic adverse events, such as cognitive impairment, sedation or respiratory depression, which are complications often associated with opioids.

Sorrento gained RTX through its acquisition of Sherrington Pharmaceuticals in 2013. At the time, the drug joined cancer drug Cynviloq in the company’s pipeline, which was later sold to NantPharma in 2015.