A Pharmacokinetic Study to Evaluate the Effect of MAALOX on Raltegravir (MK-0518) in Human Immunodeficiency Virus (HIV)-Infected Participants (MK-0518-295)

A Study to Evaluate the Effect of Staggered Dosing of a Magnesium/Aluminum Antacid on Raltegravir Pharmacokinetics in HIV-Infected Subjects on a Raltegravir-Containing Regimen

This study evaluated the effect of single doses of a magnesium/aluminum antacid (MAALOX) given 4 and 6 hours before or after administration of raltegravir, on the pharmacokinetics of raltegravir in human immunodeficiency virus (HIV)-infected participants. The study consisted of Part 1 (Periods 1, 2, and 3) and Part 2 (Periods 4 and 5), with each study period separated by a washout period of at least 2 days; Part 1 was separated from Part 2 by a Pause. Each study period had a duration of ≥2 days, and paused for evaluation of Part 1 pharmacokinetics results before continuing to Part 2. The same participants participated in Parts 1 and 2. The primary hypothesis tested (in Part 1) was that raltegravir plasma concentration 12 hours after administration (C 12 hrs) would not differ significantly from raltegravir C 12 hrs when antacid is administered 4 hours before or 4 hours after raltegravir.

Inclusion Criteria:

• On a stable raltegravir dose as part of a stable antiretroviral regimen for ≥1 month before the study
• If female, is not pregnant or breast feeding
• Body mass index ≤32 kg/m^2

Exclusion Criteria:

• Mentally or physically incapacitated, has significant emotional problems, or history of clinically significant psychiatric disorder within ≤10 years
• History of clinically significant endocrine, gastrointestinal, cardiovascular, hematological, hepatic, immunological, renal, respiratory, genitourinary, or major neurological abnormalities or disease (excluding HIV)
• History of gastric bypass surgery
• History of cancer, except adequately treated non-melanomatous skin carcinoma or carcinoma in situ of the cervix or other malignancies which have been successfully treated ≥10 years before the study
• History of chronic diarrhea within ≤3 months before the study
• History of significant multiple and/or severe allergies (food, drug, latex), or had an anaphylactic reaction or significant intolerability to drugs or food
• Had major surgery or donated or lost ≥1 unit of blood (500 mL) ≤4 weeks before the study
• Participated in another investigational trial ≤4 weeks before the study
• Taking rifampin or is unable to refrain from the use of 1) any proton pump inhibitor from 2 weeks before and throughout the study, or 2) any histamine H2-blockers, antacids, calcium supplements, or multivitamins from 2 weeks before and throughout the study
• Consumes >3 glasses of alcoholic beverages per day
• Consumes excessive amounts of caffeine beverages (coffee, tea, cola, energy drinks, or other caffeinated drinks) per day
• Currently uses or has a history of drug abuse within ≤6 months before the study