Objective: To determine whether interferon alpha-2a, when utilised as adjuvant chemotherapy following ablation of condylomata acuminata (genital warts) by cryotherapy, is effective in the prevention of recurrences.
Design: Randomised, placebo-controlled, double-blind study. Statistical analysis was by 2-tailed Fisher's Exact Test.
Patients: 97 patients with recurrent condylomata acuminata.
Intervention: 49 patients were treated with cryotherapy plus subcutaneously administered interferon alpha-2a, and 48 received cryotherapy plus placebo. Of these, 36 and 37 patients, respectively, completed the study and were evaluable.
Main outcome measure: Clinical eradication of condylomata for six months following adjuvant chemotherapy.
Results: By completion of the adjuvant chemotherapy, 10 (28%) interferon recipients and 16 (43%) placebo recipients experienced recurrences. At six months follow-up, 25 (69%) interferon and 27 (73%) placebo recipients experienced recurrences. In the six months following interferon therapy, only 31% of interferon and 27% of placebo recipients remained free of recurrences (p = 0.99).
Conclusions: Interferon alpha-2a administered subcutaneously offers no benefit as a chemotherapeutic adjuvant to cryotherapy when used alone in the therapy of genital warts in this population of patients with recurrent condylomata.