US relaxes safety warnings for imaging agents
This article was originally published in Scrip
The US FDAis notifying healthcare professionals that it has eased recent warnings for micro-bubble contrast agents. Last October it requested Lantheus Medical Imaging's Definity (perflutren lipid microspheres) and GE Healthcare's Optison (perflutren protein-type A microspheres) add "black box" warnings about the risk of serious cardiopulmonary reactions and death. The labels also added a recommendation to monitor all patients for at least 30 minutes post-administration and new contraindications for certain cardiopulmonary conditions. The FDA now has deleted many of those contraindications and eased the boxed warning to recommend intensive 30-minute monitoring only for patients with pulmonary hypertension or unstable cardiopulmonary conditions. The manufacturers must conduct postmarketing clinical and epidemiological studies to better assess the risks. Since October the agency received reports of five deaths with Definity, all in patients with severe underlying medical conditions, and none with Optison.