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

NCT01271894 | Completed Phase 3

• 1 other identifier: NCHECR-ENCORE1-PK
• Study Type: interventional
• Target: 40
• Locations: 4 countries
• Sites: 4

Brief Summary

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.

Conditions

HIV Infection

Keywords

HIV; efavirenz; pharmacokinetic

Outcome Measures

Primary Outcomes (1)

• To compare the pharmacokinetic parameters of EFV determined from blood collected over a 24-hour dosing interval in blinded samples from participants taking either 600 mg or 400 mg once daily in combination with Truvada.

  48 weeks

Secondary Outcomes (2)

• To compare the safety and tolerability of EFV 400 mg versus 600 mg given once daily.

  48 weeks

• To investigate the correlation between EFV concentration measurements from dried blood spots and concentration measured in matched plasma samples.

  48 weeks

Study Arms (2)

Reduced dose Efavirenz arm

EXPERIMENTAL

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

Drug: Efavirenz

Normal Efavirenz dose arm

ACTIVE COMPARATOR

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

Drug: Efavirenz

Interventions

Efavirenz DRUG

600 mg once daily; given as 3 x 200 mg once

Normal Efavirenz dose arm

Eligibility Criteria

• Age: 16 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)

You may qualify if:

• 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.

Sponsors & Collaborators

• Kirby Institute: lead
• Chelsea and Westminster NHS Foundation Trust: collaborator

Study Sites (4)

Hospital J.M. Ramos Mejia

Buenos Aires, Argentina

Location

Desmond Tutu HIV Foundation

Cape Town, South Africa

Location

Thai Red Cross-AIDS Research Centre, HIV-NAT Research Collaboration

Bangkok, Thailand

Location

Chelsea and Westminister Hospital

London, United Kingdom

Location

MeSH Terms

Conditions

HIV Infections

Interventions

efavirenz

Condition Hierarchy (Ancestors)

Blood-Borne Infections; Communicable Diseases; Infections; Sexually Transmitted Diseases, Viral; Sexually Transmitted Diseases; Lentivirus Infections; Retroviridae Infections; RNA Virus Infections; Virus Diseases; Genital Diseases; Urogenital Diseases; Immunologic Deficiency Syndromes; Immune System Diseases

Study Officials

• Marta Boffito, Dr.

  Chelsea & Westminster Hospital

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: SCREENING
• Intervention Model: PARALLEL
• Sponsor Type: OTHER GOV
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: January 5, 2011
• First Posted: January 7, 2011
• Study Start: September 1, 2011
• Primary Completion: May 1, 2013
• Study Completion: May 1, 2013
• Last Updated: May 13, 2013

Record last verified: 2012-11

Locations

GB (1); TH (1); AR (1); ZA (1)