R2D2 Healthy Volunteer Study

Study Name

Impact of Once-Weekly Rifapentine and Isoniazid on the Steady State Pharmacokinetics of Dolutegravir and Darunavir Boosted with Cobicistat in Healthy Volunteers

Study Number


Goal of Study

People infected with HIV often take several anti-HIV medications to control their disease. They may also need to take medications to treat a type of infection called latent tuberculosis (TB). There are a number of medications that can be used to treat latent TB. Most of these have to be taken multiple times a week or every day. However, there is a once weekly treatment for latent TB that would be easier for people with HIV to take.

The once weekly TB treatment consists of two drugs: isoniazid and rifapentine. Pyridoxine (vitamin B6) may also be given to prevent side effects from isoniazid. Isoniazid and rifapentine may increase or decrease the blood levels of some anti- HIV drugs. These changes could either increase drug side effects or make the anti-HIV treatment not work. However, since isoniazid and rifapentine are given only once a week, they may not affect the anti-HIV drug levels at all.  It is important to know how anti-HIV and anti-TB drugs affect each other so that people taking these drugs together can be treated safely.

We plan to test the once weekly TB treatment together with different anti-HIV drugs in HIV-negative healthy people. We will study these combinations in up to three different groups of study participants.  The first group will take the HIV medication dolutegravir once daily; the second group will take dolutegravir and the HIV medication cobicistat, again once daily; the third group will take dolutegravir twice daily.  You will take the HIV drugs for a total of 19 days, and receive the anti-TB drugs three times, once a week for three weeks.

We will recruit up to 35 subjects who are HIV-negative, healthy individuals between 18 and 65 years of age.  Volunteers must be in good general health. Volunteers will be compensated.

Study Design

This study is split into two parts: a screening portion and the actual study portion. If the screening tests show that you can participate in the study, you will move on to the study portion. This part will last 32-44 days and includes 9 study visits. This includes the baseline visit (before you start taking the drug) and the follow-up visits (after you have finished taking the drugs). The baseline visit will last about 2-3 hours, and will take place up to 7 days before you start taking the HIV drug. Three of the visits will last for about 12 hours (long days). The remaining five visits will last for approximately one hour (short days). All visits will take place at the NIH Clinical Center.

There are specific times when we need to collect blood samples for our study. Therefore, there is a strict calendar for when study visits will take place. We will give you a detailed study schedule to keep. The day you start taking dolutegravir will be called Day 1. Full clinic visits (long days) will take place on days 4, 14, and 19. The short visits will take place on days 5, 15, 17 or 18, 20, and 34. Then you will be done with the study.

Eligibility Criteria

  • You are age 18-65 years old, HIV-negative, and in good general health
  • You are willing to take the study medications described above
  • If you are female, you are not pregnant or breast feeding, and you agree to avoid pregnancy during the study
  • You do not take any prescription medications or over-the-counter medications
  • You have no history of a serious illness
  • You have never had or been treated for TB
  • You do not smoke
  • You agree not to use drugs or drink alcohol for the length of the study

Contact Information

Volunteer or get more information
Toll free: 1-800-411-1222
TTY: 1-866-411-1010
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Participating in Research

Watch a series of short informational videos about participating in clinical trials. These videos are intended to help potential participants understand how research works, what questions they should consider asking, and things to think about when deciding whether or not to participate in a study.

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