Long-acting dexamethasone viscous gel (SP-102) transforaminal injection for lumbosacral radicular pain

Lumbosacral radicular pain (LRP) is a condition characterized by debilitating pain and functional impairment. Epidural steroid injections (ESIs) are frequently used to relieve symptoms of LRP; there are currently no FDA-approved corticosteroid products specifically indicated for this condition. Moreover, existing products carry safety warnings against epidural administration, which have been linked to the off-label use of formulations. SP-102 (10 mg dexamethasone in a 2 ml viscous gel) is a proposed product that is formulated to provide rapid onset of action while prolonging the duration of effect, potentially resulting in extended pain relief and an improved safety profile for dexamethasone. Phase I and phase II studies have demonstrated SP-102 to be safe and well-tolerated. In phase III, SP-102 demonstrated greater pain relief compared to placebo; SP-102 reduced leg pain scores by an average of 1.1 points more than placebo over four weeks (<i>p</i> < 0.001) and extended the median time before repeat injection to 84 days compared with 58 days for placebo. SP-102 also produced an average 8.9-point reduction in the Oswestry Disability Index (ODI) from baseline versus 5.5 points with placebo (<i>p</i> = 0.015). Importantly, no serious adverse events related to the injection of SP-102 were reported.