High-grade squamous intraepithelial lesions (HSIL) of the cervix may regress with weekly application of imiquimod cream, as shown in the results of a phase II study.
A total of 90 women aged 25–50 years with cervical HSIL (cervical intraepithelial neoplasia [CIN] 2–3) were randomized to receive treatment with 250 mg of 5% imiquimod cream applied to the cervix weekly for 12 weeks followed by loop electrosurgical excision procedure (LEEP; n=49) or to undergo LEEP without preceding treatment (control; n=41).
The primary outcome of histologic regression (to CIN ≤1) in LEEP specimens was seen with greater frequency in the experimental than in the control group in the per-protocol population (23 of 38 [61 percent] vs 9 of 40 [23 percent]; p=0.001).
Likewise, more patients who received imiquimod showed negative surgical margins for HSIL (95 percent vs 70 percent; p=0.004).
In the intention-to-treat (ITT) population, results for the primary outcome were consistent with that observed in the per-protocol population.
Adverse events (AEs) in the experimental group occurred in 28 out of 38 patients in the per-protocol population (74 percent) and in 35 out of 45 in the ITT population (78 percent). AEs were mild, and abdominal pain was the most common.
Three imiquimod-treated patients developed grade 2 AEs, such as vaginal ulcer, vaginal pruritus with local oedema, and moderate pelvic pain.