Diltiazem Hydrochloride Cream for Anal Fissure

A Phase III, multicentre, randomised, double blind, placebo-controlled study in subjects having anal fissure (AF) with AF-related pain. Subjects will undertake a 1-week screening period to provide baseline data and for assessment of eligibility. At the Baseline visit (Week 0), eligible subjects (having an average Numerical Rating Scale (NRS) score of \>4 for worst pain associated with or following defaecation) will be randomised on a 1:1:1 basis to one of the three treatment groups. Subjects will receive diltiazem hydrochloride 2% cream or diltiazem hydrochloride 4% cream or placebo cream. Study treatment will be applied in and around the anus, three times daily, for up to 8 weeks. Following the Week 0 Visit, subjects will be contacted by telephone during Week 1 to ensure adequate compliance with study treatment, to ensure that study drug is being tolerated and that any concomitant medications are used at a level consistent with that prior to randomisation. Subjects will return to the clinic for safety and efficacy assessments at Weeks 2, 4, and 8 and receive a follow-up telephone call at Week 12, following cessation of therapy. Concomitant laxatives and stool softeners will be permitted, as needed, during the entire study period (screening and treatment) to ensure that constipation or passage of hard stools does not confound evaluation or improvement of the condition. Fibre supplements will be allowed but should be continued at the baseline level. Instructions on the use of the Interactive Voice Response System (IVRS) diary will be issued to subjects to record fissure-related pain (NRS) and bowel symptoms daily during the 1-week screening period, to confirm eligibility and post-randomisation to record worst anal pain associated with or following defaecation (NRS) and daily overall AF-related pain (NRS). A record of the number of times the subject has defaecated, laxative and analgesic usage will also be made as well as the number of applications of study treatmen