Randomized placebo-controlled evaluation of intramuscular interferon beta treatment of recurrent human papillomavirus

To evaluate the effectiveness and safety of interferon beta in women with recurrent cervical human papillomavirus (HPV) lesions.

Women with recurrent HPV of the cervix were assigned randomly to received either 3 million IU of interferon beta daily for 5 days, followed by 2 days of rest for 3 weeks, or placebo on the same schedule (N = 61 in each group). They were evaluated at 6 and 12 months after cytology, colposcopy, and directed punch biopsy. Comparison between groups was carried out by chi(2), Fisher exact test, and Student t test, depending on the variable. Multivariable logistic regression was used to evaluate influence of variables to treatment and categorical and continuous variables were compared by Mantel-Haenszel and Wilcoxon tests.

When treatment success rates for all patients at 6 and 12 months were compared, a highly significant statistical difference was found in the treated group compared with the placebo group [48 of 61 (79%) versus 33 of 61 (54%), P =.001, and 43 of 61 (70%) versus 26 of 61 (43%), P =.002, respectively]. Multivariable analysis showed treatment success rates with interferon beta were higher between the group with initial histopathology of cervical intraepithelial neoplasia (CIN) (odds ratio 4.86; 95% confidence interval 1.75, 13.49), and the group receiving placebo (P =.002). Side effects treatments were minimal in 70% of women; the most severe events were headaches and flulike symptoms that did not interfere with the treatment. No clinically significant changes were found in laboratory measurements of glucose or transaminases during treatment or follow-up.

Intramuscular injections of interferon beta were effective for treating recurrent HPV lesions, particularly when associated with CIN. The only side effects were mild and controllable.