Topical imiquimod treatment for human papillomavirus infection in patients with and without cervical/vaginal intraepithelial neoplasia

Objective: To evaluate the efficacy and toxicity of topical imiquimod for the treatment of persistent human papillomavirus (HPV) infection in patients with or without cervical/vaginal intraepithelial neoplasia (CIN/VAIN). Methods: Patients with persistent HPV infection (≥1 year) after a history of treatment for cervical or vaginal neoplasm but normal histology and cytology, abnormal Papanicolaou (Pap) smears without abnormal histology, and untreated histology-documented CIN/VAIN Grade 1/2/3 with HPV-positive testing were recruited. Patients were instructed to apply 250 mg of 5% imiquimod cream intravaginally on consecutive days or at least twice weekly on an outpatient basis for a minimum of 12 doses. A group of age- and previous diagnosis-matched, imiquimod-untreated historical controls (n = 20) were selected. The main outcome measures included HPV DNA detection, cytology, and colposcopy/histology at 6 months after treatment. Results: A total of 72 patients were eligible for analysis. At a median follow-up of 33.6 months, 37 patients (51.4%) had cytological/histological regression and tested HPV-negative. Six patients (8.3%) had progressive cytology/histology with persistent HPV infections. Of the 72 treated patients, 26 patients who had a normal Pap test but were persistently HPV-positive for at least 1 year had a complete regression rate of 65.4%, which was significantly different from the rate (30%) observed in the untreated historical control (p = 0.036). Six patients with histologically proven CIN2/3 or VAIN2/3 had a complete regression rate of 66.6% (4/6). Conclusions: The tolerability of intravaginal self-administered imiquimod is confirmed. Its efficacy in the treatment of women with persistent HPV infection and normal cytology warrants further randomized, controlled trials to determine appropriate dosages and scheduling.