Inclusion Criteria:

          -  Age 18 years or older

          -  Histologically confirmed stage IV clear cell Renal Cell Carcinoma and has progressed
             on/after or was intolerant to front-line treatment

          -  Must have radiologic imaging with a computerized tomography (CT) scan or magnetic
             resonance imaging (MRI) within 4 weeks of enrollment

          -  Must have at least one measurable lesion according to RECIST 1.1

          -  ECOG performance status of 0-1

          -  Adequate gastrointestinal (GI), bone marrow, liver and kidney function

          -  Life expectancy minimum of 12 weeks

          -  At least 14 days between termination of prior anticancer and administration of
             AVB-S6-500

        Exclusion Criteria:

          -  Received prior treatment with cabozantinib

          -  Currently being treated with concurrent anti-cancer therapy or any other
             interventional treatment or trial

          -  Significant cardiac disease history

          -  Has other prior or concurrent malignancy within the past 3 years except adequately
             treated basal or squamous cell skin cancer, superficial bladder cancer or carcinoma in
             situ of the prostate, cervix or breast

          -  Symptomatic CNS metastasis or metastases

          -  Active GI disease that would impact absorption of cabozantinib

          -  Nephrotic range proteinuria at screening

          -  Has had a major bleed in the last 3 months, uncontrolled hypertension despite
             treatment with Antihypertensives or is not appropriate for treatment with cabozantinib
             in the Investigator's opinion

          -  Serious active infection requiring IV antibiotics and/or hospitalization at study
             entry

          -  Has active, suspected, or previously documented autoimmune disease, defined as
             requiring systemic treatment

          -  Has known human immune deficiency (HIV) syndrome, hepatitis B, or hepatitis C