SonoGen (QW7437) is an anionically charged 2% perfluorocarbon emulsion under development as a transpulmonary myocardial ultrasound contrast agent (UCA). The SonoGen microbubbles have a reduced adherence to the negatively charged vascular endothelium and reduced coalescence. SonoGen, a second generation USCA has the theoretical potential to provide high safety and efficacy and improved tissue grayscale persistence compared to first generation fluorocarbon contrast agents.

From Sonus Pharmaceuticals
QW7437 (SonoGen) is a perfluorocarbon-based ultrasound contrast agent under development. This anionically charge-stabilized emulsion, similar to EchoGen, has been designed for echocardiographic examinations with greater safety and efficacy.

SONUS Pharmaceuticals, Inc., is engaged in the research and development of ultrasound contrast agents (USCA) and drug delivery systems for use in the diagnosis and treatment of heart disease, cancer and other conditions.
Sonus Pharmaceuticals and OncoGenex Technologies Inc., a privately held biopharmaceutical development company, announced 2008 the signing of a definitive agreement to merge the two companies. The combined company will operate as OncoGenex Pharmaceuticals, Inc.

Ultrasound Contrast Agents: