Patients with metastatic renal cell cancer will be enrolled to receive either Trovax® alone or Trovax® plus Interferon Alfa. The study will try to determine whether the use of Trovax® will delay tumor progression.

Patients with metastatic renal cell cancer will be enrolled in the study if all inclusion/exclusion criteria are met. Once the patient is enrolled, and baseline tests have been completed, the patient will start treatment.

Trovax® alone arm:

Trovax will be given as an intramuscular injection every two weeks for the first two months, then once a month for the next 2 months, and then once every 2 months for up to a year.

Trovax® plus IFN-α:

Trovax® schedule will be the same as the Trovax® alone arm. IFN will be given on the first, third and fifth day of the week for a total of twelve weeks.

At every office visit vital signs will be taken. Every eight weeks a medical history, physical exam, performance status evaluation, chest x-ray or CT scan, abdomen/pelvis CT scan or MRI will be done. A blood sample (about 8-10 tablespoons) will be taken to test the immunological response to TroVax® on the same days that the patient receives TroVax® injections.

Inclusion Criteria:

• Locally advanced or metastatic histologically confirmed clear cell or papillary cell renal carcinoma.
• Primary tumor surgically removed.
• Stable or progressive disease as defined by RECIST criteria.
• Age ≥ 18 years.
• At least one prior standard of care therapy (IL-2, IFN-α, or approved kinase inhibitor)
• At least four weeks from prior use of standard of care therapy.
• Karnofsky performance status ≥ 80%.
• Corrected Serum Calcium ≥ 10 g/dL.
• Patients on stable doses of bisphosphonates (Fosamax, Actonel, Didrocal) that show subsequent tumor progression may continue on this medication; however patients are not allowed to start bisphosphonates within one month prior to starting trial, or throughout the duration of the trial.
• Major surgery or radiation therapy completed ≥ 4 weeks prior to treatment.
• Clinically immunocompetent.
• Free of clinically apparent autoimmune disease.
• Absolute lymphocyte count ≥ 500/μL, Absolute neutrophil count ≥ 1200/μL, Platelet count ≥ 100,000/μl, Hemoglobin ≥ 9mg/dL.
• No evidence of active ischemia on Electrocardiogram (ECG)
• Women must be either post-menopausal, rendered surgically sterile, or using reliable form of contraceptive.
• Able to give informed consent and comply with the protocol.

Exclusion Criteria:

• Prior treatment with TroVax®
• No supplements of complementary medicines/botanicals are permitted during study, except for any combination of the following: multivitamins, selenium, lycopene, soy supplements, Vitamin E.
• Prior radiopharmaceuticals (strontium, samarium) within 8 weeks prior to enrollment.
• Participation in any other clinical trial within 30 days.
• Cerebral metastasis on MRI Scan.
• Currently active second malignancy, other than non-melanoma skin cancer. Patients are not considered to have a "currently active" malignancy if they have completed therapy and are considered by their physician to be at least less than 30% risk of relapse.
• Serious intercurrent infections or nonmalignant medical illnesses which are uncontrolled.
• Psychiatric illnesses that would limit compliance with protocol.
• A history of psychosis or clinical depression.
• Liver function tests (ALT, AST) more than 1.5 X upper limit of normal (ULN). Bilirubin must be within normal limits.
• Creatinine ≥ 1.5 X ULN.
• Known allergy to egg proteins.
• Known allergy to neomycin.
• History of allergic response to previous vaccinia vaccinations.
• Chronic oral corticosteroid use unless prescribed as replacement therapy in the case of adrenal insufficiency.
• Positive for HIV or Hepatitis B or C.
• Clinical indication of reduced cardiac function or an ejection fraction of ≤ 40%.
• Pregnancy or lactation
• Current chemotherapy, immunotherapy, radiation therapy, or the requirement for radiotherapy.
• No investigational or commercial agents or therapies other that those included in the protocol treatment may be administered with the intent to treat malignancy.