This is a Phase 2, prospective, randomized, dual-center, double-blind, placebo-controlled, parallel-group study designed to determine the dosing interval, efficacy and safety of SST-0225 (5.4 grams, applied up to 6 times in 24 hours, over a 48-hour dosing period) for the treatment of pain associated with DOMS.

This is a Phase 2, prospective, randomized, dual-center, double-blind, placebo-controlled, parallel-group study designed to determine the dosing interval, efficacy and safety of SST-0225 (5.4 grams, applied up to 6 times in 24 hours, over a 48-hour dosing period) for the treatment of pain associated with DOMS.

As part of the screening process, in the evening of Day -2, eligible subjects will undergo an exercise regimen designed to induce DOMS in the elbow flexor of the non-dominant arm (see Section 11). 36 (±2) hours following the exercise regimen, subjects will return to the clinic and be evaluated for eligibility into the active treatment phase of the study. Eligible subjects who experience a sufficient level of pain 36 (± 2) hours after exercise will be randomized to receive either SST-0225 or placebo.

For the first 24 hour dosing period, the subject will remain in the clinic (on-site). Subjects will apply the first dose of Investigational Product (IP) at randomization (0 hours) and a second dose upon request (PRN or as needed). All subsequent doses will be applied every 5 (±1) hours. The total number of doses shall not exceed 6 in this first 24 hour period. Subjects will also not be allowed to take any rescue medication during the first 24 hour dosing period.

Subjects will complete the Visual Analog Scale (VAS) pain/soreness on movement assessments at the following time points while on-site the first 24 hours: 0 (prior to first dose of IP), 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 16, and 24 hours post first dose of IP and immediately prior to the second dose of IP. All assessments must be completed unless the subject is asleep. Subjects will be restricted to a maximum of 8 hours of sleep in order to limit the number of missing VAS pain/soreness on movement assessments due to sleep. Immediately upon wakening on Day 2, subjects will be instructed to apply a dose of IP unless it has been less than 5 (±1) hours since their last dose of IP.

After subjects complete their 24 hour VAS pain/soreness on movement assessment, they will be released from the clinic and will continue outpatient treatment for the second 24 hour dosing period.

During the second 24 hour dosing period (24-48 hours post first dose of IP), the subject will be away from the clinic (off-site) and will apply the IP every 5 (±1) hours. The total number of doses shall not exceed 6 doses in this second 24 hour period. Rescue medication will be made available to subjects during this second 24 hour period. During this second 24 hour period, subjects will complete the VAS pain/soreness on movement assessment prior to each IP dose and at 1 hour post each dose of IP.

Refer to the Schedule of Evaluations in Appendix A (on-site evaluations) and Appendix B (off-site evaluations) for details regarding the timing of study procedures.

Healthy male and female subjects between 16 and 65 years of age.