Global initiative to fight HIV drug resistance

A radical global initiative to fight HIV drug resistance has been launched. The International HIV Resistance Response Database Initiative (RDI) will combine data from thousands of HIV patients around the world into a freely accessible database that could help physicians to choose the most effective drugs for their patients.

Mutations in the genetic code of HIV cause resistance to HIV drugs. Genotypic resistance tests are available to read these genetic changes, but it is hoped that the RDI database will enhance the predictive power of such tests by relating genetic changes in HIV directly to virological response to drug therapy, using the largest collection of clinical data of its kind in the world.

The RDI is made up of individuals, companies and institutions who are pooling key data from many thousands of patients worldwide, in particular their genotype, the drugs used in their treatment and their response to those drugs. In the future, physicians will be able to search this database for information from patients with HIV that is genetically similar to their own patient and predict which drugs are likely to be most effective.

'The relationship between genetic changes in HIV and response to drug therapy is highly complex and predicting one from the other requires vast amounts of data,' commented RDI founding member Dr Brendan Larder, chief scientific officer, Visible Genetics. 'The RDI is the first global attempt to share the clinical data necessary to develop a predictive tool that could be the key to managing HIV drug resistance in the future.'

Meanwhile an expanded global response to the AIDS epidemic based on 12 essential interventions to reduce HIV transmission could prevent some 29m new HIV infections among adults by 2010, according to an article written by a group of international experts and published in The Lancet medical review. Implementing the full package by 2005 could cut new infections by 64%, but a delay of three years would reduce the number of prevented infections by half, warned the experts, convened by the Joint United Nations Programme on HIV/AIDS (UNAIDS) and the World Health Organisation (WHO).

'Implementing these interventions immediately could dramatically alter the course of the epidemic,' said Neff Walker, of UNAIDS. 'If the interventions do not take place, we could see as many as 45m new infections by the end of the decade.'

Over the first four years, the total cost of bringing prevention programmes to scale is estimated to be US$8.4bn (€8.4bn). From 2005 onwards, the expanded prevention programme will cost an estimated $4.8bn (€4.8bn) annually. The full costs of scaling up and sustaining the effort to 2010 are put at $27bn (€27bn), or a total of some $1,000 (€1000) per infection averted.

The proportion of infections averted in different countries would vary, from a low of 40% in countries with stable or declining prevalence, such as Senegal or Thailand, to a high of 70% in countries with rapidly growing epidemics, such as Cameroon or China. Nearly a third of the benefits from the intervention package would accrue to two countries, India and China, with another 40% in sub-Saharan Africa.