Scientists have found that a relatively new drug is much more effective at treating HIV/AIDS in treatment-experienced patients, but experts in the developing world say it may be too costly for widespread use in resource-poor countries.
The research, published in The Lancet last week (6 July) concludes that darunavir-ritonavir, a drug developed to combat HIV that is resistant to other HIV drugs, should be considered as a treatment option for HIV-infected individuals at various stages of treatment.
But Walter Jaoko, chairman of the Department of Medical Microbiology at the University of Nairobi, Kenya, said that while the outcome of the research was good news, he doubts there will be a major switch from lopinavir-ritonavir — the widely used drug known as Kaletra — to darunavir-ritonavir, saying cost is likely to put this new drug beyond the reach of many patients in the developing world.
Both darunavir-ritonavir and lopinavir-ritonavir are protease inhibitors; they interfere with the virus' ability to make copies of itself.
Darunavir-ritonavir has already been shown to be effective and superior to other protease inhibitors in patients with advanced HIV/AIDS and more exposure to treatment, but had not previously been assessed in patients with less advanced disease and less treatment experience.
Lead researcher, José Madruga of the Centre of Reference and Training for DST/AIDS Brazil, and colleagues conducted a randomised, clinical trial of 595 HIV patients who were treatment-experienced but had never taken lopinavir.
At week 48 of the trial, 71 per cent patients on darunavir-ritonavir had achieved a reduction of HIV virus genetic material in the blood (a marker of HIV infection) versus 60 per cent of patients on lopinavir-ritonavir.
Jaoko said what is needed most is an effective drug that can be taken less often, and recommended that governments in the developing world continue to use first line HIV treatment and monitor patients heavily for resistance.
Paula Munderi, of the Uganda Virus Research Institute, also welcomed the findings but said that as darunavir is new, it is not on any preferential pricing scheme so would be considerably more expensive for wide scale use.
She said that because lopinavir-ritonavir is available as a combined pill, it has a lower pill burden and is cheaper. Introducing darunavir-ritonavir would be costly, she said, as ritonavir would have to be bought separately.
Munderi recommended reserving darunavir for patients for whom lopinavir-ritonavir doesn't work or isn't tolerated.
Reference: The Lancet 370, 49 (2007)