Intralesional immunotherapy with killed Mycobacterium indicus pranii vaccine for the treatment of extensive cutaneous warts

Background: Multiple cutaneous warts in adults are often symptomatic, cosmetically disabling, and difficult to treat. Killed Mycobacterium indicus pranii (previously known as Mycobacterium w, popularly known as Mw) vaccine has earlier been investigated in genital warts with encouraging results. Objective: To evaluate the efficacy and safety profile of intralesional injected killed Mw vaccine for the treatment of extensive extragenital cutaneous warts. Methods: In this study, a retrospective analysis of medical records was performed in patients with cutaneous warts treated with intralesional Mw vaccine. Only patients with more than 5 extra-genital warts, involving at least two body sites and which had not shown any signs of spontaneous regression over 6 months were treated with the vaccine. Results: Forty four patients were treated with intralesional Mw vaccine. The mean number of warts was 41.5 +/- 25.7 with a disease duration of 3.1 +/- 2.5 years. Complete clearance was achieved in 24 (54.5%) patients with a mean of 3.4 +/- 1.1 intralesional injections. Cosmetically acceptable response to therapy (>75% clearance) was achieved in 37 (84.1%) patients. Wart response at distant sites was seen in 38 (86.3%) patients. Thirty-six patients (81.8%) experienced mild therapy-related side effects. Eighteen patients with complete response were followed up for 5.27 +/- 1.7 months and none had recurrence of lesions. Conclusions: Killed Mw vaccine is safe and effective in the treatment of extensive cutaneous warts. Larger, preferably randomized controlled trials are needed to assess its efficacy vis a vis standard therapies for warts.