Safety and Efficacy of XT-150 for Facet Joint Osteoarthritis Pain

This is a Phase 2a safety and efficacy study of XT-150 in adult participants experiencing back pain due to inflammation of the facet joint, also known as facet joint osteoarthritis (FJOA), and who are eligible for intra articular glucocorticoid injection, or radiofrequency ablation of medial branches of the primary dorsal ramus of the exiting nerve root, which innervates the adjacent facet joints. Study drug will be administered at Day 0 and Day 90 by bilateral intra-articular (IA) injection into the facet capsule, at the affected spinal level (e.g. Lumbar \[L\]3-4, L4-5, or L5-Sacrum \[S\]1) as determined by imaging (e.g., Magnetic resonance imaging \[MRI\], Computed tomography \[CT\]), X-ray, etc.) and physical exam. Up to 72 participants will be randomized to placebo or one of two dose treatment groups (24 participants per treatment group). 1. 0.15 mg XT-150 (1.0 milliliter \[mL\] total delivered by two 0.5 mL injections) 2. 0.45 mg XT-150 (1.0 mL total delivered by two 0.5 mL injections) 3. Placebo (Sterile saline) (1.0 mL total delivered by two 0.5 mL injections)