An 111Indium (111In)-labeled MoAb ZME 018 which reacts with a 240 Kd melanoma-associated antigen was administered to 12 patients with metastatic melanoma. MoAb was coupled to 5 mCi 111In and infused over 2 h at doses of 2.5 mg (5 pts). 5 mg (5 pts), and 10 mg (2 pts). Total body tomograms and region of interest scans were performed at 2, 24 and 72 hours post infusion. No adverse side effects were noted. There was rapid blood pool distribution to spleen, bone, bone marrow, liver, and testes. Tumor sites could be visualized as early as 24 hours but were more easily seen at 72 hours due to less background radioactivity. Seventeen of 41 (41%) previously documented metastases imaged. More sites imaged with increasing concentrations of MoAb, i.e., 25% @ 2.5 mg; 67% @ 5 mg; 75% @ 10 mg. In two instances, uptake of 111In occurred in previously undiagnosed sites. The pharmacokinetics of MoAb were analyzed at each dose level. At the 5 mg dose, the terminal phase half-life for111In in plasma was 24.5 ± 2.7 hours. The apparent volume of distribution (Vd) wa 4.03 ± .5l similar to the plasma value, and the calculated clearance rate for 111In label was 0.259 ± 0.002 ml/kg/min. Mean urinary excretion of 111In label was 8.7 ± 0.6% of the administered dose over 48 hours after administration. The calculated pharmacokinetic parameters were independent of antibody dose. In contrast to previous studies with other anti-melanoma MoAb, ZME 018 was cleared more rapidly from plasma. Tumor localization occurred in a significant number of patients especially at MoAb doses above 2.5 mg.
|Journal||Proceedings of the American Association for Cancer Research|
|Publication status||Published - 1985|
ASJC Scopus subject areas