Therapeutic approaches to papillomavirus infections

Human papillomaviruses (HPVs) cause benign tumors (i.e., warts) and are occasionally responsible for malignant tumors such as squamous-cell carcinomas. Therapy for most warts is commonly via surgical or cytodestructive methods. Presently, only one antiviral/immunomodulatory drug is available for wart therapy; this agent, interferon alpha (IFN alpha), is approved only for genital warts (condylomata acuminata) and is expensive, relatively difficult to use, associated with systemic side effects, and somewhat slow acting. Two new antiviral/immunomodulatory drugs, imiquimod and cidofovir, have been proved to be effective and able to overcome many of the shortcomings of IFN alpha. While these two agents are pending approval, other treatments are being evaluated, such as antisense oligonucleotides and therapeutic HPV vaccines. Ln contrast to surgical and cytodestructive therapies, the goal of these new antiviral/immunomodulatory agents is not just to remove the tumor but also to reduce sufficiently the amount of latent and subclinical HPV so as to reduce the rate of recurrence.