Safety and efficacy of consecutive cycles of granulocyte-colony stimulating factor, and an intracoronary CD133+ cell infusion in patients with chronic refractory ischemic heart disease: The G-CSF in Angina patients with IHD to stimulate Neovascularization (GAIN I) trial

Background Preclinical studies suggest granulocyte-colony stimulating factor (G-CSF) holds promise for treating ischemic heart disease; however; its clinical safety and efficacy in this setting remain unclear. We elected to evaluate the safety and efficacy of G-CSF administration in patients with refractory "no-option" ischemic heart disease. Methods Twenty patients (18 males, 2 females, mean age 62.4 years) were enrolled and underwent baseline cardiac ischemia assessment (CA) (angina questionnaire, exercise stress test [EST], technetium Tc 99m sestamibi and dobutamine-stress echocardiographic imaging). Patients then received open-label G-CSF commencing at 10 μg/kg SC for 5 days, with an EST on days 4 and 6 (to facilitate myocardial cytokine generation and stem cell trafficking). After 3 months, CA and the same regimen of G-CSF + ESTs were repeated but, in addition, leukapheresis and a randomized double-blinded intracoronary infusion of CD133 + or unselected cells were performed. Final CA occurred 3 months thereafter. Results There were no deaths, but only 16 patients were permitted to complete the study. Eight events fulfilled prespecified "adverse event" criteria, including 4 troponin I–positive events and 2 episodes of thrombocytopenia. Also, frequent minor troponin I–positive events (troponin I P Conclusions Granulocyte-colony stimulating factor administration was associated with improvement in a range of subjective outcomes. However, adverse events were common, and objective measures of cardiac perfusion/ischemia were unchanged.