Sorrento Therapeutics has announced that the US Food and Drug Administration (FDA) has authorized the company's Investigational New Drug Application (IND) for Resiniferatoxin (RTX), a non-opioid, TRPV1 agonist that selectively targets afferent nerve activation involved in chronic pain states.
Sorrento intends to promptly initiate a multicenter, phase 1b clinical trial of RTX administered by epidural injection for the treatment of intractable pain associated with cancer. RTX has been granted FDA Orphan Drug Status for pain associated with end stage disease.
"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. 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 therapyi. 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 Dr. Henry Ji, president and chief executive officer of Sorrento Therapeutics, Inc.
RTX has been extensively tested in animals and is currently the subject of a Phase I clinical trial at the National Institute of Health (NIH) under a Cooperative Research and Development Agreement (CRADA). To date, 12 patients with terminal cancer pain have been treated. When injected intrathecally, RTX has been shown to directly interact with nerve cells expressing TRPV1 receptors without affecting normal sensation (touch and vibration sense) or muscle function. Preliminary results from the NIH trial demonstrate that a single injection of RTX was well tolerated at the dose levels tested and provided clinically meaningful reductions in pain and a reduced dependence on opioids. In contrast to opioids, RTX treatment did not result in systemic adverse events such as cognitive impairment, sedation or respiratory depression, and enabled patients to increase their activity levels.