The main idea of this study is that a low protein diet may alter the environment surrounding the tumor, enhancing the body's immune response leading to greater anticancer effects of treatment. This study intends to use a low-protein diet as a tool to enhance the immune response generated by immune check point inhibitor treatments.

This is a single center, randomized, open label study to assess the feasibility of a low-protein diet intervention in cancer patients who are receiving immunotherapies. Subjects will be randomized in a 1:1 ratio to either immunotherapy plus control diet arm (~20% protein content) or immunotherapy plus intervention low-protein diet arm (10% protein content).

Inclusion Criteria:

• Histologically documented solid tumor malignancies which is amenable for immunotherapy treatment with immune checkpoint inhibitors (i.e. PD1, PD-L1, CTLA inhibitors) as single agents or in combination.

• Metastatic disease as evidenced by soft tissue and/or bony metastases on baseline bone scan and/or computed tomography (CT) scan of the chest, abdomen, and pelvis

• Life expectancy of at least 6 months

• Adults ≥ 18 years of age

• Adequate hematologic, renal, and liver function as evidenced by the following:

  • White blood cell (WBC) ≥ 2,500 cells/μL
  • Absolute neutrophil count (ANC) ≥ 1,000 cells/μL
  • Platelet Count ≥ 100,000 cells/μL
  • Hemoglobin (HgB) ≥ 9.0 g/dL
  • Creatinine ≤ 2.0 mg/dL
  • Total bilirubin ≤ 2 x upper limit of normal (ULN)
  • Aspartate aminotransaminase (AST, SGOT) ≤ 2.5 x ULN
  • Alanine aminotransaminase (ALT, SGPT) ≤ 2.5 x ULN

Exclusion Criteria:

• • Eastern Cooperative Oncology Group (ECOG) performance status 2 or higher

  • Treatment with any of the following medications or interventions within 28 days of registration:

    • Systemic corticosteroids; however, use of inhaled, intranasal, and topical steroids is acceptable.
    • High dose calcitriol [1,25(OH)2VitD] (i.e., > 7.0 μg/week)

  • A requirement for systemic immunosuppressive therapy for any reason

  • Any infection requiring parenteral antibiotic therapy or causing fever (temperature > 100.5°F or 38.1°C) within 1 week prior to registration

  • A known allergy, intolerance, or medical contraindication to receiving the contrast dye required for the protocol-specified CT imaging

  • Any medical intervention or other condition which, in the opinion of the Principal Investigator, could compromise adherence with study requirements or otherwise compromise the study's objectives

undecided