Clinical Trials Logo

Clinical Trial Summary

Background:

- People who are infected with the human immunodeficiency virus (HIV) are at risk of getting certain diseases. Two of these diseases are a type of pneumonia known as PCP and a brain infection called toxoplasmosis. Most people with HIV take antiretroviral (ARV) drugs to treat HIV and lower the risk of infections. However, some ARV drugs may make other drugs used to treat PCP and toxoplasmosis less effective. Researchers want to test specific ARV drugs to see if they affect atovaquone, a drug used to treat PCP and toxoplasmosis.

Objectives:

- To see if ARV drugs atazanavir-ritonavir or efavirenz lower the blood levels of atovaquone.

Eligibility:

- Individuals between 18 and 70 years of age who have HIV.

- Participants must be taking efavirenz or atazanavir-ritonavir, or not taking any ARV drugs.

Design:

- Participants will be screened with a physical exam and medical history. They will also have blood and urine tests.

- This study has a screening visit and five study visits. Two of the study visits will last about 12 hours; the other three visits will last about 1 hour each.

- Participants will receive either a low dose or high dose of atovaquone to take for 14 days. They will record doses and any symptoms on a diary card at home.

- After 14 days, participants will have a 12-hour visit to provide blood samples. There will be a wash-out period with no doses for up to 6 weeks.

- After the wash-out period, participants will switch dose levels to either the high or low dose.

- After 14 days, participants will have a 12-hour visit to provide blood samples.


Clinical Trial Description

The incidence of opportunistic infections such as Pneumocystis jirovecii pneumonia (PCP) and Toxoplasma gondii have substantially declined in patients with HIV infection due to potent combination antiretroviral (ARV) therapy and effective prophylaxis. The drug of choice for prophylaxis and treatment of PCP and toxoplasmosis is trimethoprim-sulfamethoxazole (TMP-SMX) and sulfadiazine, respectively. In patients who cannot tolerate these first line therapies, atovaquone is a common alternative. While generally considered safe and effective, a recent drug interaction study involving a single dose of combination tablet of atovaquone/proguanil (Malarone ) in HIV-infected patients showed that atovaquone plasma concentrations were significantly lowered (compared to healthy volunteers) by 75%, 74%, and 46% in patients taking the ARV medications efavirenz (EFV), lopinavir-ritonavir (LPV/r), and atazanavir-ritonavir (ATV/r), respectively. The mechanism of this drug interaction is unknown but is presumably due to induction of uridine diphosphate glucuronsosyltransferase (UGT) enzymes responsible for the metabolism of atovaquone. The magnitude of this interaction is such that it strongly suggests a clinically relevant drug interaction between atovaquone and the aforementioned ARVs. The purpose of this study is to determine whether HIV-infected subjects receiving ATV/r or EFV-containing ARV regimens, experience reductions in atovaquone exposure under steady state conditions compared to HIV-infected patients not receiving ARV therapy.

In this open-label study, 30 HIV-infected subjects will participate in 1 of 3 groups of 10 (Groups A, B, and C). Group A will consist of 10 subjects who are already receiving combination ARV therapy containing ATV/r; Group B will consist of 10 subjects already receiving combination ARV therapy containing EFV; and Group C will consist of 10 subjects who are not currently receiving ARV therapy. All subjects in Groups A, B, and C will be randomly assigned to either receive atovaquone 750 mg twice daily for 14 days (Phase 1) followed by a 2-6 week washout period, followed by atovaquone 1500 mg twice daily for 14 days (Phase 2), or vice versa. Pharmacokinetic (PK) sampling for atovaquone will occur on Day 14 of Phase 1 and 2.

Atovaquone PK parameters will be determined using non-compartmental methods with the WinNonlin professional computer program (version 5.2; Pharsight Corporation, Mountain View, CA). The following PK parameters will be compared among the groups: area under the concentration vs. time curve (AUC ?), maximum concentration (Cmax), apparent oral clearance (Cl/F), time to reach maximum concentration (Tmax), and half-life (T (Omega)). Data from this investigation will determine whether ATV/r and/or EFV alter the steady state PK of atovaquone in HIV-infected subjects. This information will assist clinicians in choosing appropriate alternative therapies for the treatment of PCP and toxoplasmosis in patients who are not candidates for first line therapies. ;


Study Design


Related Conditions & MeSH terms


NCT number NCT01479361
Study type Interventional
Source National Institutes of Health Clinical Center (CC)
Contact
Status Completed
Phase Phase 1
Start date October 31, 2011
Completion date February 20, 2014

See also
  Status Clinical Trial Phase
Recruiting NCT06162897 - Case Management Dyad N/A
Completed NCT03999411 - Smartphone Intervention for Smoking Cessation and Improving Adherence to Treatment Among HIV Patients Phase 4
Completed NCT02528773 - Efficacy of ART to Interrupt HIV Transmission Networks
Active, not recruiting NCT05454839 - Preferences for Services in a Patient's First Six Months on Antiretroviral Therapy for HIV in South Africa
Recruiting NCT05322629 - Stepped Care to Optimize PrEP Effectiveness in Pregnant and Postpartum Women N/A
Completed NCT02579135 - Reducing HIV Risk Among Adolescents: Evaluating Project HEART N/A
Active, not recruiting NCT01790373 - Evaluating a Youth-Focused Economic Empowerment Approach to HIV Treatment Adherence N/A
Not yet recruiting NCT06044792 - The Influence of Primary HIV-1 Drug Resistance Mutations on Immune Reconstruction in PLWH
Completed NCT04039217 - Antiretroviral Therapy (ART) Persistence in Different Body Compartments in HIV Negative MSM Phase 4
Active, not recruiting NCT04519970 - Clinical Opportunities and Management to Exploit Biktarvy as Asynchronous Connection Key (COMEBACK) N/A
Completed NCT04124536 - Combination Partner HIV Testing Strategies for HIV-positive and HIV-negative Pregnant Women N/A
Recruiting NCT05599581 - Tu'Washindi RCT: Adolescent Girls in Kenya Taking Control of Their Health N/A
Active, not recruiting NCT04588883 - Strengthening Families Living With HIV in Kenya N/A
Completed NCT02758093 - Speed of Processing Training in Adults With HIV N/A
Completed NCT02500446 - Dolutegravir Impact on Residual Replication Phase 4
Completed NCT03805451 - Life Steps for PrEP for Youth N/A
Active, not recruiting NCT03902431 - Translating the ABCS Into HIV Care N/A
Completed NCT00729391 - Women-Focused HIV Prevention in the Western Cape Phase 2/Phase 3
Recruiting NCT05736588 - Elimisha HPV (Human Papillomavirus) N/A
Recruiting NCT03589040 - Darunavir and Rilpivirine Interactions With Etonogestrel Contraceptive Implant Phase 2