Phase II trial of iodine 131-labeled murine anti-tenascin monoclonal anti-body 81C6 (M81C6) via surgically created resection cavity in the treatment of patients with recurrent malignant brain tumors

Abstract

1569 Background: In a prior phase I study we established the dose of 100mCi as the maximum tolerated dose of iodine 131-labeled murine anti-tenascin antibody 81C6 (131I-81C6) injected into a surgically created resection cavity (SCRC) for the treatment of recurrent malignant glioma in adult patients. Methods: In the current phase II study we have treated 42 patients with recurrent brain tumors (GBM=32, AA=6, AO=2, infiltrating glioma = 1, metastatic =1). Patients were included into study if they had: 1) gross total resection, 2) KPS > 60%, 3) normal bone marrow and normal hepatic and renal function. All patients had received standard external beam radiation and 14 (33%) patients had received prior chemotherapy. Results: The median age was 54.5 years and 27 patients (64%) were males. All patients received 100mCi except for two patients that received 67mCi and 75mCi respectively due to the limited size of the SCRC. Toxicities were divided into acute (< 4 weeks), subacute (4–16 weeks) and delayed (>16 weeks) periods. Acute and sub-acute reversible, grade 4 hematologic toxicity was seen in 2 patients (4%) and 3 (7%) patients, respectively. Delayed grade 3 or 4 neurotoxicity was seen in 2 patients (4%). The median survival of all patients and GBM patients was 59 weeks for both groups, respectively. For patients with GBM the probability of 1-year survival is 0.56 (CI-95%; 0.41–0.78). As of December 16, 2003, 15 patients remain alive with a median follow up of 81.9 weeks for GBMs and 78.9 weeks for all patients. Conclusions: I131- labeled murine anti-tenascin antibody 81C6 is associated with minimal hematologic toxicity and provides an improvement in survival in patients with recurrent malignant glioma that have failed conventional therapy. No significant financial relationships to disclose.