Final results were announced from a phase 3 trial evaluating SP-102 (injectable dexamethasone sodium phosphate viscous gel) for the treatment of lumbosacral radicular pain, or sciatica.
SP-102 is a dexamethasone sodium phosphate viscous gel formulation that is administered by epidural injection. The investigational product contains no preservatives, surfactants, solvents, or particulates.
The phase 3 C.L.E.A.R trial (ClinicalTrials.gov Identifier: NCT03372161) compared the analgesic effects and safety of single and repeat transforaminal injections of SP-102 with placebo. The trial included 401 adults with a diagnosis of lumbosacral radicular pain. The primary endpoint was the mean change in leg pain scores, using the Numerical Pain Rating Scale, from baseline to week 4. Key secondary endpoints included change in the Oswestry Disability Index (ODI) score and the time to open-label repeat injection.
Following a single injection of SP-102, results showed a least square (LS) mean (SE) group difference of -1.08 (0.17) for the change in average daily pain in the affected leg over 4 weeks compared with placebo (P <.001). Patients treated with SP-102 reported pain relief beyond 4 weeks; the median time to open-label repeat injection was 99 days (95% CI, 78-129), according to Kaplan-Meier estimation.
Treatment with SP-102 was also associated with a 28% improvement in ODI score at 4 weeks compared with baseline. The LS mean (SE) group difference in ODI score was reported to be -6.28 (1.49) compared with placebo at week 4 (P <.001).
Additionally, statistically significant findings were reported for other secondary endpoints, including Global Impression of Change, Brief Pain Inventory, PainDETECT, and cumulative use of rescue medications (acetaminophen).
As for safety, there were no serious adverse events related to SP-102 or the injection procedure, and no reported adverse events of special interest (eg, hematoma, infection at the injection site, paraplegia).
“We are very pleased with the positive outcome and these trial results are very remarkable,” said Dmitri Lissin, MD, Chief Medical Officer of Scilex. “We believe SP-102 (SEMDEXA™) has the potential to be a transformative treatment option for sciatica, an area that has not seen any significant advancement in therapies that patients and physicians have been seeking for decades.”
The Food and Drug Administration (FDA) previously granted Fast Track designation to SP-102 for this indication.
Scilex Holding Company, a majority-owned subsidiary of Sorrento Therapeutics, Inc., announces final results for SP-102 (Semdexa™) efficacy and safety from its pivotal phase 3 clinical trial program for sciatica pain management supporting the potential for first to market opportunity. News release. Sorrento Therapeutics, Inc. Accessed March 22, 2022. https://www.globenewswire.com/news-release/2022/03/18/2406054/0/en/Scilex-Holding-Company-a-majority-owned-subsidiary-of-Sorrento-Therapeutics-Inc-Announces-Final-Results-for-SP-102-SEMDEXA-Efficacy-and-Safety-from-its-Pivotal-Phase-3-Clinical-Tri.html