08/07/08

Pivotal Biostudy of Ritonovir (RTV) 100mg Tablet

One of the challenges to the provision of boosted protease regimens, especially in developing countries is the need to keep ritonovir soft gel capsules (SGC) below 77 degrees Fahrenheit. At the International AIDS Conference in Mexico City, in a late breaker presentation on Thursday, August 6, 2008, Bernstein (Abbott Laboratories) presented preliminary bioavailability data comparing a 100mg tablet formulation of RTV to the 100mg SGC. The new tablet was the result of several reformulations to ensure stability in different climatic conditions. The tablet would not require refrigeration and has been shown to be heat stable while having a boosting effect similar to RTV SGC. The study was a single-dose, open label, cross over study in 93 healthy subjects. Serial blood samples were collected after dosing and RTV AUC and maximum plasma concentrations (C^max) were calculated. The results showed that the RTV tablet performed well, met bioequivalence data and was well tolerated. The C^max was 26% higher when compared to the SGC formulation. The investigators compared the findings to the lopinavir/ritonovir tablet that also has a similar increase in ritonovir C^max without any observed untoward effects. Abbot will soon submit registration applications for the RTV reformulation and request priority review by U.S. and E.U. authorities.


Reference:
Klein, C. A pivotal biostudy comparing ritonovir 100mg film-coated tablet to ritonovir 100mg soft gelatin capsule in healthy adult subjects. Seventeenth International AIDS Conference; August 3-8, 2008; Mexico City; Abstract THAB0405.

Source: Reporting from Mexico City for PRN News: Anita Radix, MD, MPH and Rona Vail, MD