There will be three cohorts in this Phase I, single-center, open-label, crossover study:~Cohort A (omeprazole): This is a open-label, non-randomized, one-sequence crossover study design, in which 20 healthy male subjects will be enrolled and administered a single oral dose of 40 mg omeprazole once daily for 8 days (Days 1-8) plus a single oral dose of 200 mg avanafil on Day 8. On Days 7 and 8, avanafil and/or omeprazole doses will be administered following an overnight fast of at least 10 hours.~All subjects will be confined at the Clinical Research Unit the day prior to the omeprazole administration on Day 7 and will remain confined for approximately 13 hours following the dosing on Day 8. Blood samples for determination of plasma omeprazole concentrations will be obtained from all subjects at 0 (10 minutes pre-dose), 20, 40 minutes and 1, 1.5, 2, 2.5, 3, 4, 6, 8, 10 and 12 hours post-dose on Days 7 and 8. Pre-dose blood samples for determination of omeprazole will also be taken in the morning on Days 5-6.~Cohort B (rosiglitazone): This is a randomized, open-label, two-period crossover study design, in which 20 male subjects will be randomized to receive the following treatments:~Treatment A: a single oral dose of 8 mg rosiglitazone following an overnight fast of at least 10 hours.~Treatment B: a single oral dose of 8 mg rosiglitazone plus a single oral dose of 200 mg avanafil following an overnight fast of at least 10 hours.~The two treatments in the cohort will be separated by a washout period of at least 7 days. All subjects will be confined at the Clinical Research Unit approximately from the morning of Day -1 to the morning of Day 2 in both treatment periods. Blood samples for determination of plasma rosiglitazone concentrations will be obtained from all subjects at 0 (10 minutes pre-dose) and 0.25, 0.5, 0.75, 1, 2, 4, 6, 8, 10, 12, 16 and 24 hours post-dose.~Cohort C (desipramine): This is a randomized, open-label, two-period, crossover study design, in which 20subjects identified as CYP2D6 extensive metabolizers (determined by genotyping) will be randomized to receive the following treatments:~Treatment A: a single oral dose of 50 mg desipramine following an overnight fast of at least 10 hours.~Treatment B: a single oral dose of 50 mg desipramine plus a single oral dose of 200 mg avanafil following an overnight fast of at least 10 hours. The avanafil dose will be administered 2 hours after the desipramine administration.~The two treatments in the cohort will be separated by a washout period of at least 10 days. All subjects will be confined at the Clinical Research Unit from the morning of Day -1 to the morning of Day 2 in both treatment periods. Blood samples for determination of plasma desipramine concentrations will be obtained from all subjects at 0 (10 minutes pre-dose) and 1, 2, 4, 6, 8, 10, 12, 24, 48, 72 and 96 hours post-dose. Subjects will visit the study site as outpatients in the morning for their remaining PK blood sample collection on Days 3-5.
This study will compare the pharmacokinetics of omeprazole, rosiglitazone and desipramine when administered with a single oral dose of avanafil in healthy male subjects.