Bone marrow suppression, a delay in the ability of the bone marrow to produce blood cells, is a common complication of chemotherapy. Blood cell growth factors have been approved by the Food and Drug Administration to reduce the severity and duration of neutropenia and anemia and have been in wide use for several years. Thrombocytopenia, or a low platelet count, is a common side effect of chemotherapy and it is associated with an increased risk of bleeding and may prevent patients from continuing treatment according to the planned dose and schedule of their chemotherapy regimen. Thrombocytopenia is corrected by administering platelet transfusions after patients develop low blood counts. Platelet transfusions are associated with a small, but real, risk of transmission of an infectious disease. Recently, the first blood cell growth factor, interleukin-11, was approved by the Food and Drug Administration for treatment of thrombocytopenia.
The results of a clinical study designed to evaluate whether interleukin-11 could reduce the number of platelet transfusions required by patients receiving chemotherapy was recently reported. In this clinical study, 77 patients with breast cancer were treated with Adriamycin® (doxorubicin)/Cytoxan® (cyclophosphamide) chemotherapy and Neupogen® (filgrastim). Half the patients were further treated with interleukin-11 beginning on the day following chemotherapy completion or no platelet growth factor. Patients treated with interleukin-11 required fewer platelet transfusions and had improved time to platelet recovery. Sixty-eight percent of the interleukin-11 treated patients did not require platelet transfusions compared to only 44% of the patients not receiving interleukin-11. Patients treated with interleukin-11 experienced moderate side effects, mainly related to fluid retention.
In summary, interleukin-11 can improve the time to platelet recovery and reduce the number of platelet transfusions required by patients receiving chemotherapy. (Journal of Clinical Oncology, Vol 15, pp 3368-3377, 1997)