Influence of the MDR1 Genotype on Blood Levels of Indinavir and Saquinavir in Healthy Volunteers
Status:
Completed
Trial end date:
2007-08-24
Target enrollment:
Participant gender:
Summary
This study will examine whether a particular type of gene (MDR1) in the body can affect blood
levels of two protease inhibitors, indinavir and saquinavir, which are used to treat people
with HIV. If blood levels of these drugs are too low or too high, they may not work well or
may cause side effects in patients. This study will determine how MDR1 genes might affect
absorption of these medicines.
Healthy normal volunteers between 18 and 50 years of age may be eligible for this study.
Candidates will be screened with a medical history and blood and urine tests. The blood will
be tested for:
- Routine laboratory values for assessing general health
- HIV
- MDR1 gene type
- Amount of P-glycoprotein (a protein made by the MDR1 gene) on T cells.
Participants will have blood drawn three more times, as follows:
- After one dose of the sedative midazolam (Versed(Registered Trademark)): Participants
will take an 8-milligram dose of midazolam syrup by mouth. Four hours later, a single
blood sample will be drawn through a needle in an arm vein. This part of the study will
assess the efficiency of a certain enzyme involved in metabolizing (breaking down)
indinavir and saquinavir.
- After four doses of indinavir: About a week after taking the midazolam, participants
will take 800 mg of indinavir (two capsules) 3 times a day (every 8 hours) for 1 day.
The following morning they will come to the clinic, where a catheter (flexible plastic
tube) will be placed in an arm vein for repeated blood draws. A blood sample will be
drawn, and a fourth and final dose of indinavir will be given. Seven blood samples of
about a teaspoon each will then be collected through the catheter over an 8-hour period
to measure blood levels of the drug.
- After 10 doses of saquinavir: About a week after the last dose of indinavir,
participants will start taking 1,200 mg (6 capsules) of saquinavir soft-gelatin capsules
3 times a day for 3 days. On the fourth day, participants will come to the clinic. A
catheter will be inserted into an arm vein and about 4 teaspoons of blood will be
collected for routine laboratory tests and to measure saquinavir levels. A urine sample
will also be collected for routine tests. Participants will then receive the tenth and
final dose of saquinavir, and eight blood samples of about a teaspoon each will be
collected through the catheter over an 8-hour period.
Phase:
Phase 4
Details
Lead Sponsor:
National Institutes of Health Clinical Center (CC)