Trial results presented at the International AIDS Society Conference in Sydney, Australia indicate that a combination of Aptivus (tipranavir) and Norvir (ritonavir) results in a better CD4 cell count response among treatment-experienced women than in it does among men.

The RESIST (Randomized Evaluation of Strategic Intervention in Multi-drug ReSistant Patients with Tipranavir) trials examined 1,483 positive people who had been undergoing treatment, of whom 13 percent were women. Researchers selected 117 women at random to begin taking the combination (Aptivus/r), and they saw an improved CD4 response at week 48 of treatment, with fewer side effects than men on the same regimen.