A Drug-Drug Interaction Study Between Fenofibric Acid and Efavirenz
Condition: Healthy
Study type: Interventional
Phase: Phase 1

Summary: 
      Efavirenz is predominantly metabolized by cytochrome P450 (CYP) 2B6. Fenofibric Acid is an
      inhibitor of CYP2B6. This study will evaluate the effect of multiple doses of fenofibric acid
      at steady-state on the pharmacokinetics of single-dose efavirenz in healthy adult subjects.
    

Detailed description: 
      Efavirenz is predominantly metabolized by cytochrome P450 (CYP) 2B6. Fenofibric Acid is an
      inhibitor of CYP2B6. This study will evaluate the effect of multiple doses of fenofibric acid
      at steady-state on the pharmacokinetics of single-dose efavirenz in healthy adult subjects.
      This study will not evaluate the the effects of efavirenz on fenofibric acid
      pharmacokinetics. On study Day 1 after a fast of at least 10 hours, thirty healthy,
      non-smoking, non-obese, non-pregnant adult volunteers between the ages of 18 and 45 will be
      given one oral dose of efavirenz (1 x 600 mg tablet). Fasting will continue for 4 hours after
      the dose. Blood samples will be drawn from all participants before dosing and for 24 hours
      post-dose on a confined basis at times sufficient to adequately define the pharmacokinetics
      of efavirenz. Blood sampling will then continue on a non-confined basis at 48, 72, 96 and 120
      hours post-dose. A 21 day washout period will be completed after the first dose of efavirenz
      on Day 1. On Days 22 through 30, all subjects will receive a single oral dose of fenofibric
      acid (1 x 105 mg tablet) in the morning without regard to meals. On the morning of Day 31
      after a fast of at least 10 hours, all study participants will receive co-administered single
      oral doses of efavirenz (1 x 600 mg tablet) and fenofibric acid (1 x 105 mg tablet). Fasting
      will continue for 4 hours after the dose. Blood samples will be drawn from all participants
      before dosing and for 24 hours post-dose on a confined basis at times sufficient to
      adequately determine the pharmacokinetics of efavirenz. Blood sampling will then continue on
      a non-confined basis at 48, 72, 96 and 120 hours post-dose. A further goal of this study is
      to evaluate the safety and tolerability of this regimen in healthy volunteers. Subjects will
      be monitored throughout participation in the study for adverse reactions to the study drug
      and/or procedures. Vital signs (seated blood pressure and pulse) will be measured prior to
      dosing and at approximately 1, 2, 3 and 5 hours post-dose on Days 1, 22 and 31 to coincide
      with peak plasma concentrations of both efavirenz and fenofibric acid. Blood pressure and
      pulse will also be obtained at 24 hours post-dose on Days 2 and 32 prior to discharge from
      the clinical study unit. All adverse events whether elicited by query, spontaneously
      reported, or observed by clinic staff will be evaluated by the Investigator and reported in
      the subject's case report form.
    

Intervention name(s): efavirenz; fenofibric acid 105 mg
Intervention type(s): Drug; Drug
Intervention description(s): 600 mg; fenofibric acid 105 mg
Other intervention name(s): SUSTIVA; FIBRICOR
Intervention MeSH terms: Efavirenz; Fenofibric acid
Allocation: Non-Randomized
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Basic Science