Angela D. M. Kashuba, PharmD, has been awarded a $1.7 million contract from Boehringer Ingelheim to study the drug-interaction potential of tipranavir, a new HIV protease inhibitor.
Protease is an enzyme that HIV needs in order to make new viruses. When protease is blocked, HIV makes copies of itself that can’t infect new cells.
According to Kashuba, many individual drug-drug interaction studies have demonstrated tipranavir’s high interaction potential. Kashuba’s novel phenotyping approach will help in understanding the basis for these interactions and will form the groundwork for further exploration of potentially important drug interactions.
The title of Kashuba’s project is “Evaluating the Effects of Tipranavir (with Ritonavir) Capsule and Liquid Formulation on Cytochrome P450 and P-glycoprotein Activity Using a Biomarker Cocktail in Healthy Human Volunteers.”
“The drug interaction potential in the treatment of HIV infection is unprecedented,” Kashuba says. “Our study is the first of its kind to simultaneously address interaction potential during the early and latter part of therapy and with two different formulations of the compound containing very different excipients.” (Excipients are the inert materials used to create pills and other means of delivering medication.)
This project will provide insight into the mechanisms of drug interactions seen with commonly used ritonavir-enhanced protease inhibitor therapy. The results of this study will be submitted to the Food and Drug Administration for further evaluation.
“The more information we can provide prescribers about the interaction potential of these compounds, the better we will be able to manage the complexities of treating HIV-infected patients,” says Kashuba, who is an associate professor in the Division of Pharmacotherapy and Experimental Therapeutics.