Dolutegravir in Reservoirs

The purpose of this study is to find out how well the HIV medication dolutegravir gets into different parts of the body including blood plasma, special blood cells, and rectal tissue. Specifically, investigators want to compare how fast dolutegravir lowers the HIV viral load in these three different sites. In addition, as an exploratory aim, investigators seek to learn if there are any differences in how dolutegravir acts in males and females. Results of this study will provide more information about HIV medications and their limitations. In the future, this could help create better HIV medications that can get into these hard-to-reach places and eventually cure HIV infection.

Emerging evidence indicates that sites outside of blood plasma, such as peripheral blood mononuclear cells (PBMCs) and gut-associated lymphoid tissue, remain reservoirs for HIV and play critical roles in viral persistence despite long-term potent combination antiretroviral therapy (cART). Suboptimal ARV drug concentrations within these reservoirs are thought to contribute to our inability to fully eradicate HIV. In addition, host factors such as sex have been found to impact ARV drug exposure within these sites and effect key outcomes such as time to virologic suppression. The understanding of reservoir site pharmacology and the impact on sex is limited due to several barriers: 1) Difficulty in sampling reservoir sites intensively and 2) Scarcity of women enrolled in HIV clinical research studies. Optimal drug concentrations are ideally determined early in drug development by dose-ranging studies that require intensive blood plasma sampling; this methodology is impractical to employ within tissue sites. To mitigate these barriers, the researchers propose to study the pharmacology of the integrase strand transfer inhibitor dolutegravir (DTG) within three body compartments: blood plasma, PBMCs, and rectal tissue using a novel integrated population pharmacokinetic-viral dynamic (PK-VD) modeling approach. This PK-VD modeling strategy generates concentration-response relationships with limited sampling and dosing simulations ideally suited to reservoir sites.

The primary aim of this study is to validate the integrated population PK-VD model that quantitatively describes the relationship between dolutegravir (DTG) exposure and HIV viral decay in blood plasma. The second aim of this study is to develop an integrated population pharmacokinetic-viral dynamic (PK-VD) model to describe the relationship between DTG exposure and HIV viral decay in peripheral blood mononuclear cells and rectal tissue reservoir sites. The third aim is exploratory and will investigate sex differences in DTG penetration into blood plasma, peripheral blood mononuclear cells and rectal tissue reservoirs reservoirs as well as its impact on the rectal microbiome.

Eligibility Criteria:
Inclusion Criteria:

* No ARVs in the last 6 months (from date of screening)
* No documented or suspected resistance to integrase inhibitors (dolutegravir, elvitegravir, raltegravir, or bictegravir).
* Creatinine Clearance \>50 mL/min, as calculated by the Cockcroft-Gault equation within 90 days of screen
* Liver function testing, including alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase \< 5 times upper limit of normal within 90 days of screen
* Intact gastrointestinal tract
* Able and willing to give informed consent
* Willing and eligible to initiate ARV therapy with Triumeq, DTG + Truvada (TDF/FTC), or DTG + Descovy (FTC/TAF)
* Agree to receive from their provider and pay for a prescribed supply of the drug, Tivicay® (dolutegravir/DTG), with either Triumeq, or Truvada or Descovy as determined by their primary HIV provider

  * Agree to take the prescribed medication by mouth
  * Agree that they (the participant) is responsible for bringing these medications with them to their study visits
* Willing to undergo serial blood and rectal tissue sampling
* Female participants' must be willing to have a pregnancy test done at each visit. Female participants of childbearing potential (FCB) must agree to either commit to continued abstinence from heterosexual intercourse or to use a reliable form of birth control such as oral contraceptive pills, intrauterine device, Nexplanon, DepoProvera, permanent sterilization, or another acceptable method, as determined by the investigator for the duration of the study. FCB are defined as sexually mature women who have not undergone hysterectomy or bilateral oophorectomy or have not been naturally postmenopausal for at least 24 consecutive months (i.e have had menses at any time in preceding 24 months)

Exclusion Criteria:

* Pregnant or attempting to conceive now or during the course of the study
* Self-reported or documented current anal or rectal disease prohibiting safe anoscopy and biopsies, in investigator's opinion.
* Taking concurrent medications that interfere with DTG
* Bleeding diathesis
* Platelet count \<50,000 mm3
* Medical condition that interferes with conduct of study, in investigator's opinion