Improving the cytogenetic response to interferon alpha by zidovudine (AZT) in an HIV-positive chronic myelogenous leukemia patient.

An asymptomatic HIV-positive patient with Philadelphia chromosome positive chronic myelogenous leukemia (CML) was treated by interferon-a (IFN-a) for four years. A sustained hematological response and major cytogenetic response were achieved. However, a complete cytogenetic remission (100% Ph-negative cells) was observed when zidovudine (AZT) was introduced as treatment for HIV-related immunodepression. Moreover, this complete cytogenetic remission was confirmed by quantitative PCR showing decreased BCR-ABL rearrangement at very low level. As, there are some in vitro reports demonstrating a synergistic antiproliferative effect of IFN-a and zidovudine, we discuss the possibility of synergistic effects between AZT and IFNa in the treatment of CML.