Graft-versus-leukemia: no longer an epiphenomenon editorial

Summary of Published Data Using GVL for CML Mononuclear Cell Clinical bcr-ab/(-) Acute Therapy-Related n IFN Dose (X 1 08/kg) Response by PCR Cytopenia GVHD’ Death Kolb et alla Jiang et alZo Bar et aIz2 Drobyski et ai’’ Helg et aIz3 Porter et aIz4 Novotny et aI5’ Frassoni et aI5’ Summary 4.4, 5.1, 7.4 1.8, 2.7 0.34-5.2 2.5-5.0 3.8, 5.7, 12.3 NR 2-3 infusions 0.9-7.9 0.34-12.3 0 0 1 1 1 1 3 3 10146 122%) Abbreviations: IFN, interferon-a; NR, not reported; ND, not done + Grade I-IV GVHD. t Seven of ten were treated for CML. tive effect on leukemic cells, but it enhances cell-mediated immunity and the expression of both histocompatibility molecules and accessory cell molecules (eg, LFA-3, CD58).3’-33 As shown in Table 1, most patients receiving buffy coat also received interferon-a before and/or during mononuclear cell infusions. Because some patients re- sponded to buffy coat infusions without interferon-a ther- apy, it is very unlikely that interferon-a alone is responsible for the molecular genetic remissions. In contrast to patients receiving interferon-a al~ne,~” none of the patients that achieved a molecular genetic remission with buffy coat in- fusions have relapsed, although further follow-up will be required to estimate the durability of the response. Al- though it is appealing to think that interferon-a may aug- ment the GVL effect, the data are insufficient to estimate the extent of its contribution, and this is a fruitful area for future studies.