A Study to Evaluate the Safety and Efficacy of Raltegravir (MK0518) in HIV-Infected Patients Failing Current Antiretroviral Therapies (MK0518-018 EXT2)

A Multicenter, Double-Blind, Randomized, Placebo-Controlled Study to Evaluate the Safety and Antiretroviral Activity of MK-0518 in Combination With an Optimized Background Therapy (OBT), Versus Optimized Background Therapy Alone, in HIV-Infected Patients With Documented Resistance to at Least 1 Drug in Each of the 3 Classes of Licensed Oral Antiviral Therapies

This study will investigate the safety and efficacy of raltegravir as a therapy for HIV-infected patients failing current therapy with 3-class antiviral resistance.

The primary double-blind study of raltegravir versus placebo was extended to 156 weeks and was followed by an open-label raltegravir phase in which continuing participants from both the raltegravir and placebo groups received open-label raltegravir for an additional 84 weeks for a maximum duration of up to 240 weeks. Participants who had viral failure after Week 16 may have received open-label raltegravir until Week 240.

Inclusion Criteria:

• Patient must be HIV positive with HIV RNA values that are within ranges required by the study
• Patient must have documented failure of certain antiretroviral therapy
• Patient must be on the same antiretroviral therapy for at least the past two months

Exclusion Criteria:

• Patient is less than 16 years old
• Additional study criteria will be discussed and identified by the study doctor