A recently completed drug-drug interaction study between MK-0518 (Merck's integrase inhibitor) and etravirine (TMC-125, Tibotec's second generation NNRTI), should pave the way for people to gain early access to these two important experimental anti-HIV drugs. Both drugs are currently available through expanded access programs (EAPs), which allow participants to take other experimental drugs when drug interaction data are understood.

The study, led by Merck with Tibotec's cooperation, found no significant interaction between the two drugs. No effects on blood levels of etravirine were noted when taken along with MK-0518. A small reduction in MK-0518 was seen, but it wasn't considered enough to require any change in dose.

This is welcome news for treatment experienced people, who are looking to put together an anti-HIV drug regimen with at least two or three new, active drugs. Pfizer's CCR5 antagonist, maraviroc, will soon join MK-0518 and etravirine in its own EAP. This could give many people more options to help construct a potent and durable drug combination.

It is important to note that the individual EAPs are governed by local and regional ethics boards, which will need to approve any changes in the EAP protocols before people can gain access to a new drug. This likely means that people in one area could access these two drugs together before those in other areas.

Project Inform and other community activists have long advocated for EAPs to include access to other new and experimental drugs, when there was enough information about drug-drug interactions and toxicity. With three drugs in EAPs at the same time, this issue has become particularly important. We applaud both companies for their work on this important study, and for responding to the community's call for more open access to new drugs.