PHARMACOKINETICS OF IN-111 T101 (ANTI-CD5) MONOCLONAL-ANTIBODY IN PATIENTS WITH CUTANEOUS T-CELL LYMPHOMA

The pharmacokinetics of In-111 T101, an anti-CD5 murine monoclonal antibody, were studied in 11 patients. The T101 was labeled with In-111 using a modification of the mixed anhydride method. Each patient received the content of one kit (5 mCi and 1 mg) injected alone (five patients) or mixed and co-injected with 9 mg (three patients) or 49 mg (three patients) of unlabeled T101. Dose dependent differences in biodistribution in normal organs were observed. The liver, spleen and bone marrow were sites of prominent accumulation at all dose levels. Higher doses of T101 resulted in less accumulation of In-111 in these sites and prolongation of the blood pool retention. Visualization of tumors was seen at all dose levels and did not appear to be dose dependent. These studies indicate that dose is an important determinant of T101 pharmacokinetics.