To qualify for the EARMRK program, patients must have documented resistance or intolerance to at least 1 drug in each of the 3 major classes of anti-HIV medications – nucleoside analogues (RTIs), non-nucleoside reverse transcriptase inhibitors (nnRTIs), and protease inhibitors (PIs).

Patients who qualify must not be adequately suppressing viral load on their current regimen and be at risk of clinical or immunologic progression. Their physician must determine that they need such an investigational medication to construct a potentially viable regimen. To be eligible, patients must be at least 16 years old.

The safety and efficacy of MK-0518 has not been established. To increase the likelihood that patients will respond to treatment, patients are encouraged to optimize their current regimen when beginning therapy with MK-0518. To do this, it is recommended that patients failing their current regimen receive at least 2 new antiretroviral medications to which their virus is still sensitive.

Eligible patients will be able to use MK-0518 with any available antiretroviral medications, including other medications available through expanded access research programs sponsored by other manufacturers after review and approval by the sponsor.

Patients are ineligible if they are currently or were previously participating in a clinical trial with MK-0518. They also are ineligible if they are taking any medications prohibited by the study protocol, including phenobarbital, phenytoin, and rifampin. Patients with acute hepatitis and patients who are pregnant or breast-feeding are also ineligible.Other exclusions apply.