Researchers study AIDS

Top researchers gathered to discuss their latest findings in AIDS research at the Conference on Retroviruses and Opportunistic Infections in Chicago in February.

A new protease inhibitor currently being developed by Abbott Laboratories attracted attention for its reportedly high efficacy in suppressing viral load levels.

The Phase II drug, humbly known as ABT-378 for now, was studied for 24 weeks in combination with Abbott's Food and Drug Administration-approved anti-AIDS product, Norvir.

Approximately 90% of all patients who participated in the study showed no detectable virus when they were tested at the end of the study.

Perhaps more encouragingly, none of the patients in the study dropped out as a result of side effects - a phenomenon uncommon in AIDS drug research, according to industry experts.

Protease inhibitors that are already approved by the Food and Drug Administration have recently come under attack for their possible connection to long-term side effects such as diabetes and lipodystrophy (abnormal changes in body fat).

Merck, maker of the protease inhibitor Crixivan, presented study results that countered such connections at the Chicago conference.

In a study of 159 patients taking Crixivan and a reverse transcriptase inhibitor, analysis showed that for the majority of patients with increasing viral load, the rebounding virus had mutations associated with resistance to the reverse transcriptase inhibitor but did not have mutations associated with resistance to the protease inhibitor.

The Atlantic Study

Investigators participating in the Atlantic Study, a head-to-head trial of the three different classes of AIDS drugs - nucleoside analogues, non-nucleoside reverse transcriptase inhibitors and protease inhibitors - presented other significant findings.

Preliminary findings from the study suggest that all three classes display potent antiviral activity after 24 weeks of combination therapy in antiretroviral-naïve, HIV-infected patients. The median increase in CD4 cell counts was similar in all three treatment arms, according to Christine Katlama, M.D., the researcher who presented the study's findings.

Additionally, all three combinations were reported to be safe and well tolerated, although Katlama said that long-term efficacy and safety of the three classes had yet to be determined. PR