Inclusion Criteria:

• caucasian
• healthy with no history or current clinical findings of infection or disease of the following nature: cerebrovascular, neurologic, cardiovascular, endocrine, pulmonary, immunologic, metabolic, hematologic, diabetes mellitus, glucose intolerance, gout
• non-smoker and willing to abstain from alcohol consumption during the study
• agrees to use appropriate contraception during the study period until 3 months after the final study exam.

Exclusion Criteria:

• history of significant alcohol abuse or drug abuse within 1 year prior to the screening visit
• regular use of alcohol within 6 months prior to the screening visit (more than 14 units of alcohol per week)
• use of soft drugs (marijuana) within 3 months prior to the screening visit or hard drugs (cocaine, PCP, crack) within 1 year prior to the screening visit Hepatitis B or C, HIV, history of cancer (excluding excised squamous or basal cell carcinoma)
• positive tuberculin skin test or prior TB infection
• known history of serious head injuries, seizures or any eating disorder
• received an investigational drug within 30 days prior to the first study drug administration
• known hypersensitivity/allergy to tacrolimus, cyclosporine, iothalamate iodine, para-aminohippuric acid, antibiotics or antifungals
• Body mass index (BMI) <19 or >27
• clinically significant history of psychiatric disease or a significant disability that prevents understanding or adherence to protocol
• renal dysfunction, serum creatinine or urine microalbumin above the normal age and gender-adjusted reference range of the local lab
• clinically significant abnormal liver function test indicative of impaired hepatic function
• received medications/herbal preparations that may affect the metabolism of tacrolimus or cyclosporine A within 1 month of the first study drug administration
• received any other prescription medication within 14 days prior to the first study drug administration or any over-the-counter product within 7 days prior to the first study drug administration, except for topical products without systemic absorption
• current GI condition known to affect GI motility and/or absorption
• donation of plasma (500 mL) within 7 days prior to the first study drug administration or donation/ loss of whole blood as follows: 50 mL to 499 mL within 30 days or more than 499 mL within 56 days prior to the first study drug administration
• clinically significant surgery within 4 weeks prior to the first study drug administration
• administration of steroids by injection within 12 weeks prior to the first study drug administration
• administration of any live vaccine within 7 days prior to the first study drug administration
• travel in areas where TB is endemic within 8 weeks prior to the TB skin test performed at the screening visit
• hemoglobin <140 g/L