A Randomized, Controlled Study of Repeat Dose Sustained Release Lidocaine for Treatment of Chronic Scrotal Pain

This multi-center, phase 2, randomized, single-blind, three-arm, active-controlled study is comparing repeat doses, every 28 days, of standard of care (SOC) plus ST-01 against SOC plus 1% lidocaine HCL in men experiencing chronic scrotal content pain (CSCP). The main purpose of this study is to determine if repeat injections of ST-01 are safe and effective in reducing pain. After completing a screening phase participants will be randomized into one of three groups: 1) ST-01 70 mg/mL arm, 2) ST-01 140 mg/mL arm, 3) 1% Lidocaine HCL arm (Control). Participants will receive up to 4 study treatment injections at 28-day intervals. Participants randomized to the Control arm will be given the opportunity to cross over to an ST-01 treatment arm after 2 study treatments.

Inclusion Criteria:Adult (≥ 19 years) maleUnilateral or bilateral scrotal pain lasting > 3 monthsHave nociceptive scrotal painAverage daily maximum scrotal pain score over 7 days ≥ 4 on the 0-10 NRS (Appendix 2). Participants with bilateral scrotal pain must be able to distinguish one side with pain score ≥ 4 and the opposite side must have a maximum scrotal pain score of ≤ 3.0 at baseline.Positive response to test spermatic cord block with 1% lidocaine (Lidocaine Hydrochloride Injection, USP, 1%, 10 mg/mL), defined as a decrease in pain score of at least 2 within 1 hour of injectionBaseline blood levels without clinically significant abnormalities including liver function tests (alanine aminotransferase [ALT], aspartate aminotransferase [AST], gamma-glutamyl transferase [GGT], and alkaline phosphatase [ALP]) no greater than 50% above the upper limit of normalIf sexually active, is willing to use adequate birth control methods to prevent pregnancy over the course of the studyExclusion Criteria:Negative response to test spermatic cord block, defined as absence of a decrease in pain score of at least 2 within an hour of injectionOther pain generator site with NRS pain score ≥ 4History of allergic reaction to lidocaine or any component of ST-01Any contraindication to local anesthesia with lidocaine (e.g., known hypersensitivity to anesthetics of the amide type; hypokalemia, complete heart block, anticoagulants (aspirin permitted), antiarrhythmic medication.)Active infection involving the urinary tract or scrotumInability to give consentInability to follow up according to the protocolNegative response to previous spermatic cord block