Molecular Biosystems

Molecular Biosystems was a San Diego biomedical imaging company focused on contrast agents for diagnostic ultrasound and other imaging modalities. The company developed ALBUNEX and Optison, early intravenous ultrasound contrast agents, and also advanced additional imaging candidates such as MB-840 and MBU-820 for CT and ultrasound applications. Molecular Biosystems is best known in biotech history for developing Optison, which received U.S. approval in 1997 as an ultrasound contrast agent. The company was acquired by Alliance Pharmaceutical at the end of 2000 and no longer operates as an independent active company. After the acquisition, Molecular Biosystems continued for a period as a subsidiary within Alliance.