Treatment of Kaposi’s Sarcoma with Interferon-α and Other Biological Response Modifiers

Abstract

As yet, the pathogenesis of Kaposi’s sarcoma in the setting of AIDS is not completely understood. Patients who present with Kaposi’s sarcoma as the initial manifestation of AIDS and have CD4+ cell counts of at least 2 × 108/L, no constitutional symptoms and no previous zidovudine therapy may be considered for monotherapy with high dosage interferon-α. Dosage schedules of 27 to 36MU daily or 36MU 3 times weekly are frequently employed. Response rates in this subgroup of patients are in the range of 40 to 60%, of whom one-third are histologically documented complete responders. These responses are durable; several reports have associated tumour responses with decreases of the HIV-1 p24 antigen, low incidence of opportunistic infections and prolonged survival. Combined treatment with zidovudine 500 to 800mg daily and interferon-α 9 to 18MU daily leads to tumour responses similar to those observed with single agent high dosage interferon-α. With this combination, response rates up to 30% have been also achieved in patients with a CD4+ cell count of <2 × 108/L. However, no conclusive data exist as to whether the addition of interferon-α to long term treatment with zidovudine is effective in developing or progressive Kaposi’s sarcoma.