Sorrento Therapeutics Inc. subsidiary Scilex Holding Co.'s non-opioid gel injection for a type of spinal pain reduced daily leg and back pain, according to the newly formed company's phase 2 trial results.

The corticosteroid injection for sciatica, called SP102, was tested in 19 patients enrolled in the trial, Scilex Holding's March 26 press release said. SP102 was administered via epidural injection, around the spinal cord, and 15 out of the 19 patients received repeat injections four to eight weeks after the index injection.

After the repeat injections, all 15 patients experienced a reduction in pain as measured by the Numeric Pain Rating Scale, and the current and worst pain in patients' affected leg was "mostly" reduced by over 50% for each injection in the 28-day period.

California-based Scilex Holding said all injections were well-tolerated, with no serious adverse events reported. In addition, no differences were detected between the first and second injections. Cortisol suppression time lasted up to five days and was similar for the two injection treatments, Scilex Holding said.

Currently, there are no U.S. Food and Drug Administration-approved treatments of this kind for sciatica.

SP102 is also slated for a phase 3 trial, Scilex Holding stated.

Sciatica, or lumbar radiculopathy, is caused by compression or irritation of nerve roots in the lower back and creates radiating pain down the buttocks, or one or both legs. The chronic pain condition affects more than 30 million Americans, according to Scilex Holding, and about 10 million to 11 million off-label epidural steroid injections are administered each year in the U.S. to address sciatica.