Inclusion criteria:

• Has a diagnosis of histologically confirmed advanced clear-cell or papillary renal carcinoma. No conventional therapy is available or considered appropriate by the treating physician or is declined by the patient.
• Must be on chronic hemodialysis (on a consistent regimen for the previous three months, with allowance for intermittent treatments as required for volume overload).
• Female patients of child-bearing potential and male patients must agree to use 2 forms of highly effective contraception for the duration of study treatment and after the last dose of orellanine for at least 3 months for males and 6 months for females.

Exclusion criteria:

• Diagnosis of any other malignancy within 2 years prior to enrolment, except for adequately treated basal cell or squamous cell skin cancer, superficial melanoma, or carcinoma in situ of the breast or of the cervix, or low grade (Gleason 7 or below) prostate cancer on surveillance with no plans for treatment intervention (e.g., surgery, radiation, or castration)
• Immuno-oncology therapy (IO) given in the last six (6) months prior to enrolment
• Pregnant or breastfeeding women.
• Uncontrolled medical condition including, but not limited to, ongoing or active infection or psychiatric illness/social situations that would limit compliance with study requirements, or would, in the opinion of the investigator, place the patient at increased risk.