Intralesional immunotherapy with killed Mycobacterium w vaccine for the treatment of ano-genital warts: an open label pilot study

Background  Intralesional immunotherapy with skin test antigens and vaccines has been found to be effective in the management of genital and extragenital warts.
Objective  To evaluate the efficacy and safety of intralesional Mycobacterium w (M w ) vaccine monotherapy for the treatment of ano-genital warts.
Patients and methods  Ten patients clinically diagnosed to have external ano-genital warts, including three with giant ano-genital warts (Buschke Löwenstein tumour), were included in this open-label pilot study. Two patients were human immunodeficiency virus seropositive, and one was on iatrogenic immunosuppression for renal transplantation. M w vaccine (0.1 mL) was initially injected intradermally in the deltoid region on both the sides, followed 2 weeks later by intradermal intralesional injection into the genital warts. Intralesional injections were repeated weekly until either complete clearance or a maximum of 10 injections was achieved.
Results  One patient was lost to follow-up after the first intralesional injection. In 8 out of remaining 9 patients (88.9%), the genital warts cleared completely. In one patient with giant perianal wart, the lesion was reduced to less than 5% of its volume after 10 intralesional injections, which was later electrosurgically excised. The treatment was well tolerated by the majority of the patients. The adverse reactions were noted in four patients, which were reversible. No recurrence was seen after a mean follow-up of 5.1 months.
Conclusion  Intralesional immunotherapy of ano-genital warts with M w vaccine seems to be a promising new approach, which needs to be evaluated in the randomized controlled trials.