Is imiquimod effective for the treatment of cervical intraepithelial neoplasia grade 2 or 3?
This meta-analysis of 4 small studies suggests that imiquimod is effective for the treatment of cervical intraepithelial neoplasia grade 2 or 3. Larger randomized controlled trials are needed to verify the results and to establish optimal treatment protocol. Imiquimod may be preferred over excisional treatment by individuals who plan to bear children after treatment, by avoiding pregnancy complications related to a loop electrosurgical excision procedure. Note that imiquimod is an off-label treatment of cervical intraepithelial neoplasia.
Meta-analysis (randomized controlled trials)
This was a meta-analysis of 4 randomized controlled trials (171 participants) of treatment for cervical intraepithelial neoplasia grade 2 or 3 with topical imiquimod versus placebo or no intervention. One nonrandomized prospective study with a control arm was included for assessment of adverse effects only. The authors intended to study imiquimod for vaginal intraepithelial neoplasia, but they identified only one study that addressed that outcome. Imiquimod treatment was in the form of either vaginal suppository or 5% cream used 1 to 3 times weekly — physician-applied in some studies, patient-applied in others. A total of 10% of participants discontinued treatment because of adverse effects, and systemic side effects (including fever, abdominal pain, discharge, arthralgia, and myalgia) were relatively common. The risk of bias was rated low in 2 studies, moderate in 1 study, and high in 1 study. The primary effectiveness outcome was histologic regression (61% histologic regression; odds ratio [OR] = 4.05; 95% CI 2.08 - 7.89). HPV clearance was 51% (OR = 9.50; 2.98 - 30.27). Heterogeneity for adverse events was large, except for vulvovaginal ulceration, which had a pooled probability of 2% (1% - 6%).
Linda Speer, MD
Professor and Chair, Department of Family Medicine
University of Toledo