Impact of Weekly Administration of Rifapentine and Isoniazid on Steady State Pharmacokinetics of Tenofovir Alafenamide in Healthy Volunteers (YODA)

Background: Human immunodeficiency virus (HIV) is treated with antiretroviral drugs. Many people with HIV also have the lung infection tuberculosis (TB). Most TB treatments are complicated. A simpler treatment of two TB drugs can be taken once a week. Researchers want to study how the HIV and TB drugs affect each other so people who take both can be treated safely. Objective: To study if rifapentine and isoniazid affect blood levels of the common antiretroviral TAF. Eligibility: Healthy adults ages 18-65 without HIV, TB, or hepatitis Design: Participants will fast before the screening visit. They will have a medical history, physical exam, and blood tests. Women may have a pregnancy test. During the study, participants must: Use effective birth control Not take most medicine Not drink alcohol At the baseline visit, participants will repeat screening tests and get TAF tablets. Participants will take TAF once a day for 31 days. They will keep track of doses and side effects. Over 32 days, participants will have 4 long visits and 4 short. At all visits, participants will: Fast the night before Get food Take that day's TAF Review their TAF supply Have pregnancy and blood tests Report side effects At 3 visits, participants will also take the 2 TB drugs and vitamin B6. At 3 long visits, participants will also have blood collected 8 times over 8 hours by plastic tube in an arm vein. Around Day 46, participants will fast and have blood and pregnancy tests. Two weeks later, they will get a call to see how they are feeling.