Volume 8 Number 3/4 March/April 2007

This issue of HTB is distributed with the April 2007 edition of the non-technical Guide to Changing Treatment.

One of the weaknesses of currently approved antiretroviral options is that even in treatment naive patients, 20-30% of participants in clinical trials commonly fail to achieve viral suppression to below 50 copies/mL, limiting their long-term benefit from treatment.

This may be related to prior resistance, poor absorption, or adherence, and many of these patients may be successful with a subsequent regimen, or with additional adherence support. Achieving response rates closer to 100% is clearly an important long-term goal that until now has proved elusive.

Among the results presented on new drugs at the 14th Conference on Retroviruses and Opportunistic Infections a major annual conference, from which most of the reports in this issue of HTB are drawn was a sub-set of highly treatment experienced patients who achieved near-100% response rates from using three new sensitive drugs together: raltegravir (MK-0518), darunavir and T-20 (though only around 10% of patients using raltegravir also used both darunavir and T-20).

The results on each new drug should be read in the context of each specific study and these were not the only new drugs reported we also cover maraviroc, etravirine, elvitegravir, rilpivirine and others. This included exceptional results for treatment experienced patients and also hinted at a potency that could be more optimistic for both treatment-naive patients. In the next few years, with six classes of drugs available, the formula of two nukes and either a PI or NNRTI could change significantly.

For experienced patients who are waiting for life-saving new treatments that will block further resistance, none of these drugs are sufficient unless supported by other active agents. Guidelines currently recommend using at least 2 new sensitive drugs in a combination, but just as with first-line therapy, three sensitive drugs should be the goal, and these patients should not have the potential long-term benefit from these new drug classes lost by a gamble on combinations that do not include three sensitive drugs.

For naive patients, using integrase inhibitors and possibly entry inhibitors as perhaps more tolerable cornerstones for first and second-line therapy, may show greater potency than todays drugs though cost will then become a determining factor, as in the UK at least, the continued pressure on drug budgets seems unlikely to leave much room for newer options if they are more expensive that the current standard of care therapies.

The overview of drug interaction studies in this issue is provided by the team at Liverpool University.

We would also like to highlight the publication by the British HIV Association (BHIVA) of a new Standards of Care report focusing on proposals for restructuring of HIV services in the UK, and encourage feedback into these plans.