Acceptability and feasibility of Micralax® applicators and of methyl cellulose gel placebo for large-scale clinical trials of vaginal microbicides

Objective(s): To evaluate the feasibility and acceptability of the Micralax(R) applicator and of methyl cellulose placebo gel for use in vaginal microbicide clinical trials. Design: A two-centre prospective study following women for 2 months. Setting: Two primary health care clinics in South Africa. Patients, participants: Female volunteers (n = 28) 18 years or older who were HIV negative and had no clinically detectable genital tract abnormalities or reproductive tract infections. Interventions: Participants used pre-filled Micralax(R) applicators to apply methyl cellulose gel every other day, as well as up to 1 h before to every episode of vaginal sex. Main outcome measure(s): Consistency in the weight of gel dispensed per application; side-effects attributed to applicator or gel use; and acceptability of the applicator and of the gel. Results: Over a 2 month follow-up period the 22 women completing the study reported no adverse events related to gel or applicator use. The Micralax(R) applicator proved acceptable. The gel was not too messy and did not reduce sexual frequency or pleasure. On average, the applicator dispensed 4.7 ml per use (close to the 4 ml planned). Conclusions: The Micralax(R) applicator performs well as a delivery system for potential vaginal microbicides; and methyl cellulose is an appropriate placebo for future microbicide trials. (C) 2001 Lippincott Williams & Wilkins.