Detection of Coronary Artery Disease by Echocardiography using Imagify



--Apr. 28, 2008-- Acusphere Inc. announced the submission of a New Drug Application (NDA) to the U.S. Food & Drug Administration (FDA) for approval to market its lead product candidate, Imagify (Perflubutane Polymer Microspheres for Injectable Suspension). Imagify is an ultrasound imaging agent for the detection of coronary artery disease, the leading cause of death in the United States. The NDA includes data from studies of Imagify in more than 1,000 patients worldwide, including two pivotal international multi-center Phase III clinical trials, RAMP-1 and RAMP-2 (Real-Time Assessment of Myocardial Perfusion).

--Nov. 07, 2007-- Acusphere Inc. announced that data from its Phase 3 RAMP-1 (real time assessment of myocardial perfusion) and RAMP-2 clinical trials of Imagify (Perflubutane Polymer Microspheres) for Injectable Suspension were presented at the annual American Heart Association meeting in Orlando, Florida. The results from these international multi-center trials indicate that Imagify Perfusion Stress Echo is an effective and well-tolerated, minimally invasive approach to evaluating chest pain patients at risk for heart attack.

--May. 01, 2007-- Acusphere Inc. announced today that its Imagify agent had completed a second successful late-stage human clinical trial that met endpoints for both accuracy and sensitivity. The test did not meet endpoints for "specificity", but Acusphere said a previous late-stage clinical trial met this requirement. Acusphere CEO Sherri Oberg said in a statement that the company believes its results will support a strong application to the U.S. Food and Drug Administration for marketing approval. The company will make a filing by the end of 2007. Acusphere has a lot riding on Imagify. It has already built a manufacturing plant in Tewksbury intended to handle production of the agent once it is approved.


Myocardial contrast echocardiography is a rapidly evolving technique for the assessment of myocardial perfusion, capable of detecting flow-limiting coronary artery disease. Imagify (perflubutane polymer microspheres) injectable suspension, also known as AI-700, is a new ultrasound contrast agent that satisfies all the characteristics of an ideal agent for the assessment of myocardial perfusion. Preliminary studies with Imagify indicate that it is comparable with radionuclide perfusion techniques (presently the most widely used imaging technique to assess coronary artery disease) without the disadvantages of radiation and lack of availability at the bedside.

Potential benefits of cardiac ultrasound enhanced with a perfusion imaging agent include the following:

Clinical Information

  • Cardiac stress ultrasound with a perfusion imaging agent has the potential to provide information on both myocardial perfusion and real-time wall motion simultaneously.
  • Cardiac stress ultrasound has the potential to provide real-time information without requiring post-processing and analysis.

No Radioactivity

  • Ultrasound contrast agents usually do not require special licensing for storage and handling, have a long shelf life, and are convenient to use and store.
  • Nuclear stress tests use radioactive materials that create additional costs due to preparation, storage and disposal requirements.

Less Time

  • Nuclear stress tests typically take five hours, while ultrasound procedures typically take less than one hour.

Lower Expense

  • The cost of performing an ultrasound imaging procedure using ultrasound with a perfusion contrast agent is expected to be significantly less than for a nuclear stress test.

Most current existing ultrasound contrast agents, however, are vulnerable to ultrasound pressure, resulting in significant destruction of the microbubbles when imaged under routine conditions such as continuous imaging mode or higher ultrasound power output. This not only decreases the efficacy of the contrast agents but also causes artifacts (such as near-field microbubble destruction that could be misinterpreted as perfusion defect) and the inability to image the heart continuously because of excessive microbubble destruction. AI-700 (Acusphere Inc, Cambridge, Mass) is a third-generation intravenous contrast agent of synthetic polymer microspheres containing perfluorocarbon gas, designed to overcome the above mentioned problems often seen with other contrast agents.


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