Ribavirin for Patients With Recurrent/Metastatic (R/M) Human Papillomavirus (HPV)-Related Malignancies

Inclusion Criteria: * Recurrent and/or metastatic HPV-related carcinoma of the cervix, anus, vagina, vulva, penis, or oropharynx. The cancer diagnosis must be confirmed by slide review in the MSKCC Department of Pathology. HPV positive status must be demonstrated by HPV in situ-hybridization (ISH) and/or by p16 immunohistochemistry (IHC). Note: For cervix squamous cancer, HPV ISH test or p16 IHC test is not required, because all cervix squamous cancers are presumed to be HPV-associated. * Adults (≥ 18 years of age) * ECOG performance status of 1 or better * Measurable disease according to RECIST 1.1 criteria * Availability of archived tumor tissue for correlative studies (5 unstained slides) * Adequate organ function, as follows: * Adequate bone marrow reserve: absolute neutrophil count (ANC) ≥ 1.5 X 109/L, platelets ≥ 160 X 109/L, hemoglobin ≥ 10 g/dL * Hepatic: total bilirubin within ULN (upper limit of normal); alkaline phosphatase (AP), aspartate transaminase (AST) and alanine transaminase (ALT) ≤ 2.0 X ULN * Renal: Serum creatinine ≤ 1.3 mg/dL. Patients with serum creatinine \> 1.3 mg/dL may be eligible if creatinine clearance (CrCl) ≥ 55 mL/min based on the standard Cockroft and Gault formula. * Ability to swallow oral medication. * Patients of childbearing potential must have a negative serum pregnancy test within 14 days of treatment. Patients must agree to use a reliable method of birth control during and for 6 months following the last dose of study drug. * At least one prior systemic therapy regimen for R/M HPV-related carcinoma Exclusion Criteria: * History of hemolytic anemia or thalassemia * Current treatment or known prior treatment with ribavirin * Active infection or serious underlying medical condition that would impair the patient's ability to receive protocol treatment. * Current therapeutic anticoagulation with Coumadin (warfarin) * Known brain metastases