A phase I study of interleukin-6 after autologous bone marrow transplantation for patients with poor prognosis Hodgkin's disease

We performed a pilot study of human recombinant IL-6 (SDZ ILs 969) in 6 patients with poor prognosis Hodgkin's disease following autologous bone marrow transplantation (ABMT) to determine its safety and tolerability. IL-6 was administered the day following bone marrow infusion by subcutaneous injection once daily at a dose of 1 mu/kg/day to 3 patients and 2.5 mu g/kg/day to 3 patients and was continued for 6 weeks or until platelet engraftment (>50 x 10(9)/L independent of transfusion). No severe or life threatening toxicities were seen at either dose level. A reversible elevation in alkaline phosphatase occurred in 4 patients and all patients complained of headache, myalgias, and fever. Gastrointestinal toxicity was low, grade 3-4 mucositis occured less frequently than in similarly-treated historical controls receiving GM-CSF. Serum concentrations of other cytokines such as IL-3 and G-CSF after ABMT differed from results obtained in transplant recipients given GM-CSF. The median time to an ANC >0.5 x 10(9)/L was 25.5 days and to a platelet count of >20 x 10(9)/L independat of transfusion was 35.5 days. Engraftment was no different from controls. Five patients relapsed at a median of 5 months post-ABMT and four remain alive at a median of 12 months post-ABMT. We conclude that IL-6 administration is safe and well tolerated in patients following ABMT. Further efforts to evaluate its effect on hematopietic recovery as well as relapse following transplantation in a larger patient series are warranted.