Phase I Study of Intra-Tumoral, Radiolabeled, Anti-Tenascin Monoclonal Antibody 81C6 in the Treatment of Patients With Malignant Primary Brain Tumors

OBJECTIVES:

• Determine which one of two delivery techniques (bolus injection versus microinfusion) provides the greater distribution volume of iodine I 131 antitenascin monoclonal antibody 81C6 (I 131 MAb 81C6) administered intratumorally in patients with newly diagnosed or recurrent malignant primary brain tumors.
• Determine the maximum tolerated dose of I 131 MAb 81C6 delivered intratumorally in these patients.
• Evaluate the efficacy of I 131 MAB 81C6 delivered intratumorally in these patients.

OUTLINE: This is a randomized, dose-escalation study.

Patients are randomized to receive iodine I 131 antitenascin monoclonal antibody 81C6 (I 131 MAb 81C6) by one of two delivery techniques first, then crossover to receive the antibody by the other technique 3 days later. Each patient then receives a therapeutic dose by the most efficient method. Both methods are delivered via a stereotactically-placed intralesional catheter.

• Arm I: Bolus injection method
• Arm II: Microinfusion delivery method Cohorts of 3-6 patients receive escalating doses of I 131 MAb 81C6, with dose escalation occurring separately for each arm. After 10 patients are enrolled and the best method of administration is determined, all subsequent patients receive I 131 MAb 81C6 by that method, and the maximum tolerated dose (MTD) is determined. The MTD is defined as the dose at which no more the 2 of 6 patients experience dose-limiting toxicity.