The Effect of Hypertension Medications on Renal Blood Flow Measurements in Healthy Males (MK-0000-127)

Study Overview
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Brief Summary
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This study will evaluate the effect of Aliskiren and Losartan on renal blood flow using PAH clearance, PC MRA and ASL MRI methodologies.

Official Title
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A Randomized, Double-Blind, Placebo-Controlled, 4-Treatment, 3-Period, Incomplete Block, Balanced Crossover Study to Evaluate the Effects of a Single Dose of Aliskiren and Losartan on Renal Blood Flow Measurements in Healthy Male Subjects

Conditions
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Hypertension

Intervention / Treatment
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* Drug: Aliskiren
* Drug: Aliskiren
* Drug: Comparator: Losartan
* Drug: Comparator: Placebo to Aliskiren
* Drug: Comparator: Placebo to Losartan


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subject is in generally good health Subject is willing to avoid unaccustomed strenuous exercise during the study Subject agrees to consume ONLY the study-specified diet during all domiciled periods Subject has been a non-smoker for at least 3 months prior to study Subject will refrain from smoking or using any tobacco products during the study Subject agrees to refrain from consuming alcohol or caffeine during the domiciled periods and agrees to limit alcohol and caffeine consumption throughout the study Exclusion Criteria: Subject has contraindication to MRI scans Subject has a history of stroke, seizure, or major neurological disorders Subject uses illicit drugs or has a history of drug/alcohol abuse Subject has had major surgery, has donated or lost 1 unit of blood, or has been in another investigational study in the last 4 weeks Subject has a history of multiple and/or severe allergies to drugs or food

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 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: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: 1<br>Aliskiren 600 mg | Drug: Aliskiren<br>* Single dose of four 150 mg tablets (600 mg total) Aliskiren in one of three study periods. There will be at least 10 days between each study period.<br>Drug: Comparator: Placebo to Losartan<br>* Single dose of placebo to Losartan 100 mg in one of three study periods. There will be at least 10 days between each study period.<br>|
| Active Comparator: 2<br>Aliskiren 150 mg | Drug: Aliskiren<br>* Single dose of one 150 mg tablet of Aliskiren in one of three study periods. There will be at least 10 days between each study period.<br>Drug: Comparator: Placebo to Aliskiren<br>* Three or four tablets placebo to Aliskiren 150 mg in one of three study periods. There will be at least 10 days between each study period.<br>Drug: Comparator: Placebo to Losartan<br>* Single dose of placebo to Losartan 100 mg in one of three study periods. There will be at least 10 days between each study period.<br>|
| Active Comparator: 3<br>Losartan 100 mg | Drug: Comparator: Losartan<br>* Single dose of one 100 mg tablet Losartan in one of three study periods. There will be at least 10 days between each study period.<br>Drug: Comparator: Placebo to Aliskiren<br>* Three or four tablets placebo to Aliskiren 150 mg in one of three study periods. There will be at least 10 days between each study period.<br>|
| Placebo Comparator: 4<br>Placebo | Drug: Comparator: Placebo to Aliskiren<br>* Three or four tablets placebo to Aliskiren 150 mg in one of three study periods. There will be at least 10 days between each study period.<br>Drug: Comparator: Placebo to Losartan<br>* Single dose of placebo to Losartan 100 mg in one of three study periods. There will be at least 10 days between each study period.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| change in renal plasma flow as measured by PAH clearance and on renal blood flow as measured by ASL MRI after single-dose Aliskiren |  | 2-5 hours post dose of study drug | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| change in renal plasma flow as measured by PAH clearance and on renal blood flow as measured by ASL MRI after single-dose Losartan |  | 2-5 hours post dose of study drug |