Two Clinical Trials to Evaluate Pharmacokinetics of Unboosted and Boosted Atazanavir Used Alone or Co-administered With Tenofovir DF in Healthy Korean and Caucasian Male Volunteers

Study Overview
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Brief Summary
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Compared to those of Caucasians, the plasma levels of atazanavir (ATV) may be higher in Koreans with the same dosage regimen(s). If so, even unboosted ATV could be used with tenofovir DF (TDF) which lowers the concentration of ATV. The investigators plan to investigate the pharmacokinetic features of ATV with or without TDF in healthy Korean and Caucasian volunteers and compare the ethnic differences.

Official Title
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Two Randomized, Open-labeled, Parallel Designed Multiple-dose Clinical Trials to Evaluate Pharmacokinetics of Ritonavir-unboosted and Ritonavir-boosted Atazanavir Used Alone or Co-administered With Tenofovir DF in Healthy Korean and Caucasian Male Volunteers

Conditions
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Atazanavir

Intervention / Treatment
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* Drug: atazanavir
* Drug: Atazanavir(ATZ) and Tenofovir(TDF)
* Drug: Atazanavir(ATZ) + Ritonavir
* Drug: atazanavir(ATZ) + tenofovir(TDF) + ritonavir


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Men aged 20 to 55 years old, with a weight more than 50 kg and with appropriate body mass index (BMI) values within 19-28 kg/m2. Agreed voluntarily to participate to the study and comply with the study protocol with written permission. Exclusion Criteria: Has history of liver, kidney, respiratory, musculoskeletal, endocrinologic, neuropsychiatric, hemato-oncologic, or cardiovascular problem(s). Has history of hypersensitivity or clinically significant adverse drug reaction(s) to the study drugs, same class of the study drugs, or other drugs including aspirin and antibiotics. Drinks excessive caffeinated beverages (caffeine >10 units/day), alcohol beverages (alcohol >21 units/week) or smokes excessively (>20 cigarettes/day) or has history of alcoholism. Has been excluded by the researchers due to abnormal findings in screening EKG and/or blood tests

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 55 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: atazanavir<br>400 mg/day for 2 days | Drug: atazanavir<br>* 400 mg/day for 2 days<br>|
| Experimental: Atazanavir and Tenofovir<br> | Drug: Atazanavir(ATZ) and Tenofovir(TDF)<br>* ATZ 400 mg with TDF/day for 2 days<br>|
| Experimental: Atazanavir and Ritonavir<br> | Drug: Atazanavir(ATZ) + Ritonavir<br>* ATZ 300 mg + Ritonavir 100 mg/day for 2 days<br>|
| Experimental: Atazanavir + tenofovir + ritonavir<br> | Drug: atazanavir(ATZ) + tenofovir(TDF) + ritonavir<br>* ATZ 300 mg + Ritonavir 100 mg with TDF/day for 2 days<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pharmacokinetic analysis | maximum concentration at steady status(Cmax,ss) |  | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pharmacokinetic evaluation | Area under the time-concentration curve, at steady status, at tau(τ) (AUCτ,ss) |  |