Background: Cryotherapy is commonly used as ablative treatment of external genital warts (EGW). However, after cryotherapy recurrence of lesions affects on average 45% (42-70%) of subjects in the 6 months after the treatment. Sinecatechins 10% are an effective topical treatment of EGW. A low recurrence rate (<6%) was observed in pivotal phase 3 trials conducted with this product. Topical sinecatechins have demonstrated to significantly reduce the recurrence rate of EGW in subjects treated with laser therapy (The PACT-I trial). So far, no prospective data are available regarding the efficacy of sinecathechins as immunomodulator sequential therapy after cryotherapy in EGW subjects. The purpose of this study was to assess the rate of recurrence lesions after the use of topical sinecatechins 10%, as sequential proactive immunomodulation treatment after cryotherapy in subjects with EGW (The PACT-II Trial: the postablation immunomodulator treatment of condylomata with sinecatechins trial) (Trial Registration number: ISRCTN44037479).
Methods: In a prospective, assessor-blinded, multicenter trial a total of 55 subjects with a diagnosis of multiple EGW (36 men and 19 women, mean age 47±10 years) and a mean lesion number of 9±7, after their informed consent, were enrolled in the study. All subjects were treated with cryotherapy (an average of 2 sessions). After the ablative treatment, all subjects were instructed to apply sinecatechin 10% ointment 3 times daily for 4 consecutive months. The primary study endpoint was the evaluation (assessor-blinded) of recurrent lesions after 6 months (2 month of follow-up after the conclusion of topical treatment). The secondary study endpoints were the appearance of new EGW lesions (lesions affecting area not treated by cryotherapy) and the local tolerability.
Results: At baseline, the mean number of EGW lesions were 9±7. After cryotherapy, the mean lesions number were reduced to 1.6±1.8. At month 4, EGW mean lesion number were 0.2±0.4 (P=0.0001 vs. after cryotherapy). At month 6, recurrence of lesions was detected in 10 subjects (18%; 95% CI: 9-30%) with an average of 1.4 lesions. Of these recurrent lesions, 6 occurred in completely healed lesions site after cryotherapy and 8 in partially healed ones. New lesions (outside the cryotherapy treated area) were observed in 10 subjects. The product was very well tolerated. No serious side effects were reported. Three subjects reported moderate skin irritation on the application site.
Conclusions: The PACT-II Trial has shown that the recurrence rate of EGW lesions after successful cryotherapy using sinecatechins as immunomodulator sequential therapy is lower in comparison with the percentage documented in the literature without sequential therapy (20 vs. 45%). These results are in line with already published data evaluating the role of sinecatechins after laser therapy (PACT-I trial). Future comparative, double-blind controlled trials assessing the efficacy of different proactive strategies are warranted.