A Safety Study of 212Pb-Pentixather Radioligand Therapy

Inclusion Criteria: * ability to provide independent consent * adequate bone marrow function (platelet count ≥ 100,000; hemoglobin of ≥ 10 g/dL; neutrophil count ≥ 1,500 cells/mm3) * adequate kidney function (creatinine clearance of ≥ 50 mL/min using the Cockcroft-Gault equation * adequate liver function (serum bilirubin ≤ 3x the upper limit of normal, AST ≤ 5x the upper limit of normal, and ALT ≤ 5x the upper limit of normal) * failed initial therapy or declined further therapy known to confer benefit * have at least one lesion ≥ 2 cm that is positive for CXCR4 as demonstrated by Lead-203 Pentixather SPECT/CT Exclusion Criteria: * major surgery within 4 weeks of consent * antoher investigational agent within 4 weeks of consent * uncontrolled illness including, but not limited to, ongoing or active infection that would necessitate a delay in therapy or cause a hospital admission, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, hepatic cirrhosis or severe impairment, or psychiatric illness/social situations that would limit compliance with study requirements. * prior solid organ transplant * cytotoxic or antineoplastic therapy within 21 days of consent (42 days for nitrosoureas) * antibody therapy within the 21 days of consent * allogenic bone marrow or stem cell transplant, or any stem cell infusion, within 84 days of consent * pregnancy * breastfeeding * refusal to comply with birth control requirements during study