Long-term safety and antiretroviral activity of hydroxyurea and didanosinein HIV-infected patients

Long-term safety, immunologic effects, and antiretroviral activity of hydro xyurea and didanosine were evaluated in this retrospective study. Some 65 H IV-1-infected patients (39 of whom were antiretroviral naive) were studied (mean baseline CD4 count, 362 cells/mm(3); mean plasma HIV-1 RNA viral load , 4.8 log(10) copies/ mi). The mean treatment duration was 20 months. Overa ll tolerance was good: 15 patients interrupted treatment because of clinica l or biologic side effects. Four patients experienced a category B event. P atients had a mean increase of 27 CD4 cell counts after 12 months, of 112 a fter 24 months and of 59 after 36 months. They had a mean 1.03 log(10) fall in HIV-1 RNA after 12 months, 1.59 log(10) after 24 months, and 1.27 log(1 0) after 36 months. After 12 months, 35% developed an HIV-1 RNA viral load <200 copies/ml, 53% after 24 months, and 36% after 36 months. Those whose v iral load became undetectable after 12 months have significantly lower base line RNA values (p =.03). Fourteen patients had a viral load <3.4 log(10) c opies/ml after 24 months of the double therapy. A prolonged viral load supp ression can be achieved using a simple combination of two drugs that are in expensive and well tolerated.