Safety and Efficacy of SP-103 in Subjects With Moderate to Severe Acute Lower Back Pain

This is a Phase 2, randomized, double-blind, placebo-controlled, parallel group, multicenter study to evaluate the safety and efficacy of SP-103 in subjects with moderate to severe acute lower back pain. Three to 7 days after the Screening Visit, subjects will return for a Baseline visit to verify electronic Diary compliance, collect urine samples for a drug screen and pregnancy test (for women of child-bearing potential), and complete baseline clinical rating scales. If subjects meet all the study inclusion criteria and none of the exclusion criteria, subjects will be randomized into the study. Subjects are expected to apply investigational product for 12 hours per study day, from days 1 through 28, and to record the time of investigational product applications and removals in an electronic diary. Subjects will capture daily numeric pain rating scores and topical adhesions assessments in the electronic diary each evening prior to the removal of investigational product. On day 28, subjects will return to the study site to complete the End of Study visit.