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.