FDA Drug Safety Communication

FDA is reviewing clinical trial data about a potentially serious effect on the heart from the use of Invirase (saquinavir) in combination with Norvir (ritonavir). The data suggest that together the two drugs may affect the electrical activity of the heart by QT or PR interval prolongation.

FDA's analysis of these data is ongoing. However, healthcare professionals should be aware of this potential risk for changes to the electrical activity of the heart. Invirase and Norvir should not be used in patients already taking medications known to cause QT interval prolongation such as Class IA (such as quinidine) or Class III (such as amiodarone) antiarrhythmic drugs; or in patients with a history of QT interval prolongation, pre-existing conduction system disease, ischemic heart disease, cardiomyopathy, or underlying structural heart disease.

This communication is in keeping with FDA's commitment to inform the public about its ongoing safety review of drugs. The agency will update the public as soon as this review is complete.

View the full FDA Drug Safety Communication on FDA.gov