CBM588 in Combination With Nivolumab and Cabozantinib for the Treatment of Advanced or Metastatic Kidney Cancer

This phase I trial evaluates the effects of CBM588 in combination with standard therapies, nivolumab and cabozantinib, in treating patients with kidney cancer that has spread to other places in the body (advanced/metastatic). The digestive microbiome may have an effect on how patients respond to treatment, and previous research shows that a specific bacteria found in the gut (Bifidobacterium) may predispose participants to a better response to standard therapies. CBM588 is a strain of bacteria that can restore species of Bifidobacterium to the microbiome. The primary aim of this study is to determine how CBM588 changes the microbiome of patients with metastatic renal cell carcinoma. Immunotherapy with monoclonal antibodies, such as nivolumab, may help the body's immune system attack the cancer, and may interfere with the ability of tumor cells to grow and spread. cabozantinib may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. Giving CBM588, nivolumab, and cabozantinib may kill more tumor cells.

PRIMARY OBJECTIVE: I. To determine the effect of clostridium butyricum CBM 588 probiotic strain (CBM588) (in combination with cabozantinib/nivolumab) in modulation of the gut microbiome in patients with metastatic renal cell carcinoma (mRCC). SECONDARY OBJECTIVES: I. To evaluate the effect of CBM588 on the clinical efficacy of the cabozantinib/nivolumab combination. II. To assess the effect of CBM588 on systemic immunodulation of the cabozantinib/nivolumab combination in patients with mRCC. III. To assess the effect of CBM588 on toxicities such as diarrhea and nausea using Common Terminology Criteria for Adverse Events (CTCAE) version (v)5 criteria with the cabozantinib/nivolumab combination in patients with mRCC. OUTLINE: Patients are randomized to 1 of 2 arms. ARM 1: Patients receive nivolumab intravenously (IV) over 30 minutes on day 1 and cabozantinib S-malate orally (PO) once daily (QD). Cycles repeat every 28 days in the absence of disease progression or unacceptable toxicity. ARM 2: Patients receive CBM588 PO twice a day (BID), nivolumab IV over 30 minutes on day 1, and cabozantinib S-malate PO QD. Cycles repeat every 28 days in the absence of disease progression or unacceptable toxicity. After completion of study treatment, patients are followed up at 30 days.