Adjuvant Photodynamic Therapy Does Not Prevent Recurrence of Condylomata Acuminata After Carbon Dioxide Laser Ablation—A Phase III, Prospective, Randomized, Bicentric, Double-Blind Study

Abstract

Recurrence after therapy for anogenital warts, or condylomata acuminata (CA), is common. Topical photodynamic therapy (PDT) using 5-aminolevulinic acid (ALA) is efficient in the treatment of CA, but one problem with PDT is the limited penetration depth of photosensitizer and light. Pre-PDT vaporization of CA using a carbon dioxide (CO(2)) laser may enhance efficacy. CO(2) laser ablation was followed by ALA-PDT in a phase III prospective randomized bicenter double-blind study to prevent recurrence of CA. One hundred seventy-five patients with CA received CO(2) laser vaporization plus adjuvant ALA-PDT (n=84) or adjuvant placebo-PDT (n=91). A 20% ALA or placebo ointment was applied to the CA area 4 to 6 hours before CO(2) laser vaporization, followed by illumination with red light (600-740 nm, 100 mW/cm(2), 100 J/cm(2)). Cumulative recurrence rate 12 weeks after treatment was 50.0% in the ALA-PDT group, versus 52.7% in the placebo-PDT group (p=.72). No statistically significant difference between groups was detected with regard to recurrence rates up to 12 months after treatment. No major complications were observed. Adjuvant ALA-PDT of CA after CO(2) laser ablation was well tolerated, but no significant difference with regard to recurrence rate was observed from CO(2) laser vaporization alone.