At the time of the analysis, dose levels tested ranged from 0.0005 to 0.030mg/m2 per day, respectively. Among the 15 evaluable patients at dose levels of 0.015 and 0.030mg/m2 per day, two complete responses, two partial responses and two minimal responses were observed.
One of the complete responses was in a patient with mantle cell lymphoma. In addition, six patients experienced stable disease and three patients progressed during treatment. The full data set will be presented at the 2007 annual meeting of the American Society of Hematology (ASH).
Six patients at dose levels 0.015 and 0.030mg/m2 per day had tumor infiltration in the bone marrow, a location from which relapses of these diseases potentially emanate. The bone marrow infiltration in five out of six patients decreased during treatment with MT103, with a complete clearance of tumor cells from the bone marrow in three patients and partial clearance in the other two patients.
Christian Itin, president and CEO of Micromet, said: “We are pleased to see the number of objective responses to MT103 in a relapsed patient population, and are looking forward to providing a more detailed update at ASH about our exciting new clinical data with the first BiTE antibody in clinical trials.”