Conditions: Drug Therapy, Combination
Allocation: NON_RANDOMIZED | Intervention model: CROSSOVER
Enrollment: 20
Healthy volunteers: no

Brief summary:
This is an open-label, randomized, 2-period crossover study, to evaluate the pharmacokinetics, pharmacodynamics, safety and tolerability of warfarin in combination with Tamiflu (oseltamivir) in participants stabilized on warfarin. Participants will be randomized to receive either their warfarin followed oseltamivir and warfarin, or by oseltamivir and warfarin followed by warfarin. The treatment periods will be separated by a washout period of at least 4 days. Participants will continue receiving warfarin once daily at a prescribed usual dose throughout the study.

Detailed description:

Arms:
arm 1: Participants will receive warfarin (on Days 1-5) in Treatment Period 1, followed by a washout period of at least 4 days (maximum 8 days). Participants will then receive oseltamivir 75 milligram (mg) (orally twice daily on Days 1-4 and once on Day 5) and warfarin in Treatment Period 2, and attend a follow-up visit 4-12 days after the last dose in Treatment Period 2. Participants will continue receiving warfarin once daily at a prescribed usual dose throughout the study. arm 2: Participants will receive oseltamivir 75 mg (orally twice daily on Days 1-4 and once on Day 5) and warfarin in Treatment Period 1, followed by a washout period of at least 4 days (maximum 8 days). Participants will then receive warfarin (on Days 1-5) in Treatment Period 2, and attend a follow-up visit 4-12 days after the last dose in Treatment Period 2. Participants will continue receiving warfarin once daily at a prescribed usual dose throughout the study.

Interventions: intervention 1: Oseltamivir intervention 2: Warfarin
Intervention descriptions: intervention 1: Oseltamivir 75 mg orally, twice daily for 4 days and once on Day 5. intervention 2: Warfarin once daily, at a dose determined through titration by participants' usual hematologist.

Protocol document: