Inclusion Criteria:
1. Male or female subjects age ≥ 18 years with a history of treated colorectal cancer with unresectable metastases of the primary colorectal cancer to other organs.
2. If HIV-1 positive, viral load must be \< 50 copies/ml and participant must be on stable ART for at least 3 months.
3. Demonstrate positive tumor expression of CCR5 by IHC.
4. Adult patients with metastatic colorectal cancer (mCRC) who have been previously treated with fluoropyrimidine-, oxaliplatin-, and irinotecan-based chemotherapy, an anti-VEGF therapy, and, if RAS wild-type and medically appropriate, an anti-EGFR therapy.
5. Histologically confirmed for microsatellite stable MSS colorectal cancer by PCR, Immunohistochemistry (IHC) or Next-generation sequencing (NGS).
6. Have measurable disease per RECIST 1.1
7. Have an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1.
8. Expected survival of at least three months
9. No anti-cancer treatment within the last four weeks or at least 5 half-lives prior to treatment (except for palliative radiation therapy from which the patient has recovered from all adverse events).
10. Patients must have adequate organ and bone marrow function within 28 days prior to registration, defined as:
i. Acceptable liver function:
1. Total bilirubin ≤ 1.5 × upper limit of normal (ULN) OR direct bilirubin ≤ ULN for participants with total bilirubin levels \> 1.5 × ULN
2. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤ 2.5 × ULN (≤ 5 × ULN for participants with liver metastases).
ii. Acceptable renal function:
a) GFR ≥ 30 mL/min iii. Acceptable hematologic status:
1. Hemoglobin ≥ 9 g/dL Note: Criteria must be met without packed red blood cell (pRBC) transfusion within the prior 2 weeks. Participants can be on stable dose of erythropoietin (≥ approximately 3 months).
2. White blood cells \> 2500/µL
3. Absolute neutrophil count \> 1500/µL
4. Platelet count \> 100 000/µL.
11. Clinically normal resting 12-lead ECG at Screening Visit or, if abnormal, considered not clinically significant by the Principal Investigator.
a) No QTC interval exceeding 460 milliseconds (ms) for females, no QTC interval exceeding 450 ms for males.
12. Both male and female patients and their partners of childbearing potential must agree to use two medically accepted methods of contraception (e.g., barrier contraceptives \[male condom, female condom, or diaphragm with a spermicidal gel\], hormonal contraceptives \[implants, injectables, combination oral contraceptives, transdermal patches, or contraceptive rings\], or one of the following methods of birth control (intrauterine devices, tubal sterilization or vasectomy) or must practice complete abstinence from intercourse of reproductive potential from study entry to 6 months after the last day of treatment (excluding women who are not of childbearing potential and men who have been sterilized).
13. Females of childbearing potential (FOCBP) must have a negative serum pregnancy test at Screening Visit and negative urine pregnancy test prior to receiving the first dose of study.
14. Male participants must agree to use contraception and refrain from donating sperm for at least 120 days after the last dose of study intervention.
15. Patients must have the ability to understand and the willingness to sign a written informed consent prior to registration on study.
Exclusion Criteria:
1. Known severe hypersensitivity towards monoclonal antibodies.
2. Clinically significant active coronary heart disease and cardiovascular insufficiency with hypotension (systolic blood pressure \<100 mmHg) per PI discretion
3. Prior history of other malignancies, except early-stage prostate cancer or basal cell carcinoma that has been surgically resected.
4. Active hepatitis B (defined as having a positive hepatitis B surface antigen \[HBsAg\] test) or hepatitis C or known viral infections.
5. Are pregnant or breastfeeding or expecting to conceive or father children within the projected duration of the study, starting with the Screening Visit through 120 days after the last dose of study intervention.
6. Has known psychiatric or substance abuse disorders that would interfere with cooperation with the requirements of the trial.
7. Stroke and/or transient ischemic attack within 6 months prior to screening.
8. Placement of a cardiac stent or bypass surgery within 6 months of screening
9. Tumor invasion of a large vascular structure (e.g., pulmonary artery, superior or inferior vena cava).
10. Is currently participating in or has participated in a study of an investigational agent or has used an investigational device within 4 weeks prior to the first dose of study treatment.
Note: Participants who have entered the follow-up phase of an investigational study may participate as long as it has been 4 weeks after the last dose of the previous investigational agent.
11. Active, uncontrolled bacterial, viral, or fungal infections, requiring systemic therapy.
12. Use of anabolic steroids within 6 months of screening
13. Inability to follow protocol.
Active drug
Caution: ClinicalTrials.gov appears to have newer eligibility criteria than the version saved here. Review the current criteria in ClinicalTrials.gov.