About The Study

Assess the antiviral effects and safety profile of Hydroxyurea (HU) in combination regimens for the treatment of antiretroviral naive, HIV-infected adults in a controlled study.

Study Approach

This was a randomized study to evaluate the virologic and immunologic effects and the safety of the following combinations:

  • ddI plus AZT
  • ddI plus D4T
  • ddI plus hydrea
  • ddI plus D4T plus hydrea

Neither the physician nor the volunteer knew to which of the four groups the volunteer had been assigned. The study monitored changes in viral burden and CD4 count.

Study population

Antiretroviral naive volunteers with CD4 count between 200 and 500 mm3 were enrolled in 8 study centers in Argentina, Brazil, Canada and Mexico. Preliminary data are presented for 120 volunteers, comparing pooled HU arms (59 patients) vs pooled non-HU arms(61 patients). Demographic data for the two groups appeared balanced. The mean viral load was 4.47 for the HU group and 4.35 for the non-HU group.


Viral load measurements of the HU group showed an average decline of 1.59 log10 at week 12 and an average decline of 1.76 at week 24. For the non-HU group, the mean decline was 1.59 and 1.45 at weeks 12 and 24, respectively. The proportions of patients with undetectable viral load (< 400 copies/mL) were 56% at Week 12 and 60% at Week 24 for the HU group. These proportions were 58% and 43% in the non-HU group. In the HU group, mean changes in CD4 counts (cells/mm3) were 4 and 6 at weeks 12 and 24, respectively. In the non-HU group, we noted an increase in CD4 counts of 89 at week 12 and 91 at week 24. There were no clinically significant differences in adverse reactions between the two groups. Only one volunteer (1.6%) treated with HU showed marked neutropenia.


The addition of HU to the ddI containing regimens provides a safe, cost effective alternative for the treatment of HIV-infection without notable adverse events.

Note: These results were taken from the abstract 287/12235 presented at the 12th World AIDS Conference in Geneva.