- Imiquimod is part of a new class of drugs called immune response modifiers.
- It stimulates the innate immune response through interferon- a production, as well as acquired immunity by activating T-helper 1 cells.
- The result of the release of cytokines, such as TNF-a and INF-a, is activation of both anti-viral and anti-tumor immunity that can be prolonged in the form of immune memory.
- Toll-like receptor 7 on antigen presenting cells are key to their activation by imiquimod.
- Imiquimod was first indicated and used for external genital and perianal warts/ condyloma acuminata. Other HPV warts have also been treated by this drug, often in combination with more conventional therapy including cryotherapy and CO2 laser therapy, in immunocompetent and immunosuppressed patients.
[Berman B, et al. Skin Therapy Lett. 2002; 7(9):1-6.]
- Other viral infections such as molluscum contagiosum have also responded to this drug.
- The second wave of therapy has used the anti-tumour effect to clear actinic keratosis, basal cell carcinomas, lentigo malignas and Bowen’s disease either alone or in combination with other treatments.