• To evaluate whether intravenous (IV) 131-I-TM-601 provides tumor-specific localization in patients with recurrent or refractory metastatic (including brain metastases) solid tumors [ Time Frame: between 1 - 72 hours post study dose ] [ Designated as safety issue: No ]
  
• To determine the distribution and dosimetry of intravenously administered 131-I-TM-601 [ Time Frame: between 1 - 72 hours post study dose ] [ Designated as safety issue: Yes ]
  
• To determine the safety and tolerability of IV administered 131-I-TM-601. [ Time Frame: within 28 days of last study drug administration ] [ Designated as safety issue: Yes ]
  

Drug: 131-I-TM-601 (chlorotoxin)
Patients will be administered 1 - 3 (Test Doses A, B, and Dose C) escalating doses of 131I-TM601 by intravenous (IV) administration. Each dose will be administered as a single administration, scheduled at one-week intervals. Test Dose A - 10 mCi (+/- 20%)/0.2 mg TM601 (131I-TM601) Test Dose B - 20 mCi (+/- 20%)/0.4 mg TM601 (131I-TM601) Dose C - 30 mCi (+/- 10%)/0.6 mg TM601 (131I-TM601)

This is a multi-center, open label, non-randomized, sequential, within-patient dose-escalation study in patients with recurrent or refractory primary solid tumors with metastatic involvement (including brain metastases). Patients will be administered 1 to 3 (Test Doses A, B and Dose C) escalating doses of 131-I-TM-601 by intravenous (IV) administration, with dosimetry (imaging-based evaluation of the dose reaching the target sites) conducted prior to and following administration of each dose. Whole body dosimetry on critical structures including, but not limited to, bone marrow, bladder, brain, liver, and thyroid will be determined. The preliminary results from Test Dose Levels (A and/or B) for each patient will be analyzed prior to treating patients with Dose C.

Patients will be followed until 28 days following the final dose, with a complete clinical assessment and imaging evaluations at the final follow-up visit.