A Phase 1b, Open-Label Parallel Study Evaluating CLR 125 in Patients With Relapsed or Refractory Triple Negative Breast Cancer
The goal of this clinical trial is to evaluate the safety and efficacy of 3 different dose levels of CLR 125 in patients with advanced triple negative breast cancer. The main questions the study aims to answer are: * What dose and regimen should be used in future trials of CLR 125 in patients with advanced triple negative breast cancer. * What side effects do participants have when taking CLR 125. Participants will: * Have CLR 125 administered via infusion 4 times each cycle; repeated every 8 weeks. * Visit the clinic once every 3 weeks for checkups and testing. * Report any side effects or new medications. Some participants may also receive one dose of CLR 131 to evaluate the amount of radiation delivered to various organs and to the tumor. These participants will: * Have 4 scans completed over 2 weeks * Have blood drawn 6 times over 2 weeks.
• Unequivocal TNBC histology \[ER and PR less than 10% each and HER-2 negative\].
• Patients that have progressed after at least one prior standard therapeutic regimen given alone or in combination (including, but not limited, to: chemotherapy, immunotherapy, sacituzumab govitecan-hziy, trastuzumab deruxtecan).
‣ Patients who have received neo-adjuvant or adjuvant therapy must be at least one year from that treatment regimen.
• Patient is ≥ 18 years of age.
• ECOG performance status of 0 to 2.
• Life expectancy ≥ 6 months.
• Patient must meet the following laboratory criteria:
‣ Platelets ≥ 75,000/uL \[75 x 10\^9/L\]
⁃ White blood cell (WBC) count ≥ 3000/uL
⁃ Absolute neutrophil count ≥ 1500/uL
⁃ Hemoglobin ≥ 9 g/dL
⁃ Estimated glomerular filtration rate ≥ 30 mL/min/1.73 m2 (as reported by the local lab)
⁃ Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤ 2.5 × upper limit of normal (ULN)
⁃ Bilirubin \< 1.5 × ULN
• At least one measurable lesion, as defined by RECIST v1.1, with longest diameter at baseline ≥ 10 mm (excluding lymph nodes, for which the short diameter must be ≥ 15 mm).
• Patients with known brain metastases must have completed any radiotherapy or systemic treatments for brain metastases prior to enrollment; by investigator assessment be considered stable with no new signs or symptoms for at least 1 month, and on a stable dose of steroids (unchanged for three weeks prior to registration or on a steroid tapering regimen).
• Patients must express willingness and ability to comply with scheduled study visits, treatment plans, laboratory tests, and other study procedures.
• Patient or their legally authorized representative must have the ability to understand and provide signed informed written consent before the initiation of any study-related procedures.
• Female patients of childbearing potential must have a negative pregnancy test within 24 hours of dosing.
• Women of childbearing potential must agree to use a highly effective method of contraception during the study and for 12 months following administration of the study drug. Highly effective methods of contraception include combined (estrogen and progestogen containing) hormonal contraceptives associated with inhibition of ovulation, progestogen-only hormonal contraception associated with inhibition of ovulation, intrauterine device, intrauterine hormone-releasing system, vasectomized partner, or sexual abstinence. Women who have undergone hysterectomy, bilateral oophorectomy, or bilateral tubal ligation, or are post-menopausal (no menses for 12 months without an alternative medical cause) are considered to be of non-childbearing potential.
• Men who are able to father a child must agree to use a condom during the study and for 12 months following administration of the study drug.