Abstract: Huang Dan*, Ju Mei, Qian Yihong, Zhou Pingyu, Tang Zengqi, Yang Xifang, Zhang Xiaohua, Guo Qing, Chen Kun, Gu Heng. *Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical Collage, Nanjing 210042, China Corresponding authors: Chen Kun, Email: kunchen181@aliyun.com; Ju Mei, jumeiweng@163.com 【Abstract】 Objective To compare the safety and efficacy of two doses of topical 20% 5-aminolevulinic acid （ALA） in photodynamic therapy（PDT） for condyloma acuminatum of the vulva on the premise that the area to be topically treated is fixed. Methods An open, randomized, parallel-group controlled clinical trial was performed in three institutions in eastern China. Patients with condyloma acuminatum of the vulva were randomly divided into two groups according to a random number table: group A and group B applying 0.5 ml and 0.25 ml of 20% ALA solution, respectively, to an area measuring 2 cm in diameter followed by polyethylene film coating and adhesive tape fixation. All the patients were treated for three times with an interval of 7 － 10 days. Efficacy was evaluated and adverse reactions were recorded after each treatment, and follow-up was scheduled on week 1, 4, 8, 12 and 24 after the last treatment for the observation of recurrence rate. Results A total of 88 patients with genital condyloma acuminatum were enrolled in this trail, and 81 patients completed all the treatment, including 45 patients with 55 warts in group A and 36 patients with 49 warts in group B. After 3 times of treatment, significant differences were observed in wart clearance rate （98.18% vs. 85.71%, χ2 = 5.67, P < 0.05） and cure rate （97.77% vs. 80.55%, χ2 = 6.66, P < 0.05）. The overall recurrence rate during 12 weeks after the last treatment was significantly lower in group A than in group B（9.09% （4/44） vs. 35.71% （10.28） , χ2 = 7.74, P < 0.01）. Adverse reactions mainly included local swelling, pain and erosion, and all spontaneously subsided within 1 to 5 days. Further more, no significant difference was observed in the occurrence rate of adverse reactions between group A and B （33.33% vs. 30.55%, P > 0.05）. Conclusions Given that the area to be topically treated is fixed, 0.5 ml of 20% ALA is superior to 0.25 ml of 20% ALA in the photodynamic treatment of condyloma acuminatum of the vulva with favorable efficacy, reduced recurrence and similar adverse reactions.

Key words: Condylomata acuminata, Aminolevulinic acid, Photochemotherapy, Dose-response relationship, drug