Pharmacokinetic Assessment Shows Value in HIV

Pharmacokinetic assessments are an important component of deciding which administration route is optimal for patients with human immunodeficiency virus (HIV) infection who are being treated with antiretroviral agents, according to a new case study.¹

A team of researchers headed by Kristina Brooks, PharmD, of the Clinical Pharmacokinetics Research Unit, Clinical Center Pharmacy Department, National Institutes of Health (NIH), Bethesda, MD, reported on the case of a patient with advanced HIV infection and a “complicated medical history” that included long-term intractable nausea/vomiting. The patient was receiving antiretroviral medication via a Roux-en-Y jejunostomy (J)-tube.

The researchers performed pharmacokinetic assessments to compare differences in antiretroviral drug absorption and plasma exposure following oral and J-tube administration of dolutegravir, tenofovir disoproxil fumarate, and emtricitabine. They also compared these results with published pharmacokinetic data in HIV-infected individuals.

The J-tube and oral administration routes were similar in terms of exposure to dolutegravir and tenofovir, the researchers write. However, emtricitabine exposure was 38% lower when administered via J-tube.[HMICMS 

When the researchers compared these findings to reference data in HIV-infected individuals who were taking these medications orally, they found that exposure to dolutegravir and tenofovir was 75% to 76% and 55% to 61% lower, respectively, following both routes of administration.

Emtricitabine exposure was similar to the reference data following J-tube administration, and 71% higher following oral administration.

The researchers noted that adequacy of drug exposures following the J-tube and oral administration routes is “largely unknown,” leading to challenges in making dosing recommendations and attaining viral suppression. They state that their report “highlights the importance of performing pharmacokinetic assessments in patients with the potential for impaired drug absorption to ensure antiretroviral treatment success.”

Reference

1. Brooks KM, Garrett KL(2), Kuriakose SS, et al. Decreased absorption of dolutegravir and tenofovir disoproxil fumarate, but not emtricitabine, in an HIV-infected patient following oral and jejunostomy-tube administration. [published online May 27, 2017]. Pharmacotherapy.  doi: 10.1002/phar.1960.

This article originally appeared on MPR