ClinicalTrials.Veeva

Menu

The Intensive Pharmacokinetics Sub-study of Encore1 (ENCORE1-PK)

K

Kirby Institute

Status and phase

Completed
Phase 3

Conditions

HIV Infection

Treatments

Drug: Efavirenz

Study type

Interventional

Funder types

Other

Identifiers

NCT01271894
NCHECR-ENCORE1-PK

Details and patient eligibility

About

Safety and efficacy are key issues in antiretroviral therapy (ART) selection. Efavirenz (EFV) is an important component of combination ART in treatment naive individuals. Like many drugs, there are inter-individual differences in the efficacy and tolerability of EFV. The Encore1 study provides an opportunity to examine the pharmacokinetics (PK)(processes by which a drug is absorbed, distributed, metabolized, and eliminated by the body) of EFV in blood samples collected over a 24-hour dosing interval in participants receiving either standard 600 mg or reduced 400 mg dose EFV once daily.

Full description

This sub-study will investigate the relationships between dosage, EFV plasma concentrations, toxicity and virological efficacy. EFV concentrations in dried blood spots and matched plasma and will be evaluated to determine the utility of dried blood spot measurements in measuring EFV plasma concentrations. Measurements dried blood spots could potentially be a cheap and easy alternative to measurements in plasma. Dried blood spots can be easily collected from venous blood or fingerprick, do not need plasma separation and potentially need less stringent storage conditions during shipment.

Enrollment

40 patients

Sex

All

Ages

16+ years old

Volunteers

No Healthy Volunteers

Inclusion and exclusion criteria

All participants enrolled into the main Encore1 study at participating sub-study sites will be eligible to participate.

Participants must meet the following additional inclusion criteria prior to intensive pharmacokinetic assessment. Inclusion Criteria:

  • provide written sub-study consent at or before week 0
  • taken randomized study drugs for at least 4 weeks but less than 8 weeks
  • taken EFV in the evening for at least 7 days
  • taken all EFV doses over the 3 preceding days.

Trial design

Primary purpose

Screening

Allocation

Randomized

Interventional model

Parallel Assignment

Masking

Double Blind

40 participants in 2 patient groups

Reduced dose Efavirenz arm
Experimental group
Description:
Participants randomized in main study to receive EFV (400 mg once daily; 2 x 200 mg + 1 x placebo once daily) plus tenofovir/emtricitabine (300/200 mg) fixed-dose combination once daily
Treatment:
Drug: Efavirenz
Drug: Efavirenz
Normal Efavirenz dose arm
Active Comparator group
Description:
Patients randomized in the main study to receive EFV (600 mg once daily; 3 x 200 mg once daily) plus tenofovir/emtricitabine (300/200 mg) fixed-dose combination once daily
Treatment:
Drug: Efavirenz
Drug: Efavirenz

Trial contacts and locations

4

Loading...

Data sourced from clinicaltrials.gov

Clinical trials

Find clinical trialsTrials by location
© Copyright 2025 Veeva Systems