Patients with HIV infection have a significant risk of recurrence following local ablation of intraepithelial neoplasia; thus, anogenital epithelial may become an increasingly important cause of morbidity, and possibly mortality, as the HIV epidemic matures. Clinical studies of non-HIV-infected subjects have established that synthetic retinoids inhibit the progression of epithelial preneoplastic conditions and some neoplastic states.~In the Phase I portion of the study, 20 patients per site each receive isotretinoin in escalating doses. If a patient experiences grade 2 or worse toxicity (or grade 3 or worse hypertriglyceridemia), dose is reduced to the previously tolerated dose for the remainder of the 6 week period. Patients are then reassessed for anal neoplasia; those with no progression and no grade 2 or worse toxicity receive an additional 6 weeks of isotretinoin in combination with interferon alfa-2a. For Phase II of the study, a separate group of patients who have undergone ablative therapy are randomized to one of three arms (26 patients/arm): isotretinoin alone at the dose tolerated by at least 60 percent of patients in Phase I; isotretinoin plus interferon alfa-2a; or observation only. Treatment continues for 48 weeks.
PRIMARY: In Phase I, to define a broadly tolerable dose of isotretinoin that can be used in combination with interferon alfa-2a (IFN alfa-2a). In Phase II, to determine trends in efficacy of isotretinoin alone or in combination with IFN alfa-2a as chemoprevention (preventing progression or recurrence) of anal intraepithelial neoplasia ( AIN ) / squamous intraepithelial lesions ( SIL ) in patients with HIV infection.~SECONDARY: To evaluate the effects of isotretinoin alone or in combination with IFN alfa-2a on immune function markers, human papillomavirus (HPV) type, and HPV DNA levels.~Patients with HIV infection have a significant risk of recurrence following local ablation of intraepithelial neoplasia; thus, anogenital epithelial may become an increasingly important cause of morbidity, and possibly mortality, as the HIV epidemic matures. Clinical studies of non-HIV-infected subjects have established that synthetic retinoids inhibit the progression of epithelial preneoplastic conditions and some neoplastic states.