Purpose: For the patient-administered treatment of anogenital warts, 0.5% podofilox (podophyllotoxin), one of the active compounds of podophyllin, has been shown to be more effective than the vehicle alone. This study was designed to evaluate the safety and efficacy of 0.5% podofilox treatment followed by prophylaxis.
Patients and methods: A total of 103 patients were entered in stage 1 of the study. Stage 1 was an open label study, and patients self-administered 0.5% podofilox twice daily for 3 consecutive days per week for 4 weeks. A total of 100 patients remained available for efficacy and safety analyses. At the end of stage 1, patients who had a complete response proceeded to stage 2 of the study. Patients who had a 50% to 99% reduction in measured total wart area were offered cryotherapy every 10 days, up to 5 times. If cleared of warts, they were also entered into stage 2. A total of 57 patients were enrolled into stage 2, a double-blind, randomized, placebo-controlled prophylactic study of 0.5% podofilox self-administered once daily for 3 days per week for 8 weeks, on the sites of healed warts. A total of 45 patients in stage 2 were available for efficacy analysis.
Results: By the end of stage 1, 68% of the warts had disappeared, and 29 of 100 patients (29%) had a complete response. A total of 49 patients had a 50% or greater improvement in wart area and underwent cryotherapy. Rates of local side effects after 1 week of treatment were 57% for inflammation, 39% for erosion, 47% for pain, 48% for burning, and 44% for itching. However, these symptoms and signs were mostly mild to moderate in intensity and diminished over time. Therefore, overall treatment was well tolerated. In stage 2, only 4 of 21 patients (19%) in the podofilox group experienced a recurrence as opposed to 12 of 24 (50%) in the placebo group (P = 0.031). As in stage 1, the side effects were modest, and the drug was well tolerated.
Conclusion: This study confirms the efficacy and good tolerance of 0.5% podofilox in the treatment of anogenital warts. It also establishes the safety and superior efficacy of patient-administered podofilox over the vehicle alone as prophylaxis against recurrence of lesions. Although long-term efficacy and tolerance remain to be established, podofilox appears to be a useful agent in the control of this disease.