|
 New York, US - Philips is developing an
ultrasound-based drug delivery technology that is
designed to increase the effectiveness and reduce
the side effects of chemotherapy treatment for
certain types of cancer. The system proposes the use
of drug-loaded
microbubbles, no larger than red blood cells, that
can be injected into the patient’s bloodstream,
tracked via ultrasound imaging, and then ruptured by
a focused ultrasound pulse to release their drug
payload when they reach the desired spot. Because
the drugs would only be released at the site of the
diseased tissue, the patient’s total body exposure
to them could be limited. For certain types of
treatment – for example, chemotherapy for breast
cancer – this could help to reduce unpleasant side
effects.
The use of microbubbles in conjunction with medical
ultrasound imaging is not new. However, at the
moment in clinical practice, microbubbles are only
used as contrast agents for example to highlight
blood in the ultrasound images – an application that
relies on the fact that microbubbles reflect
ultrasound much better than blood or soft tissue.
The drug delivery technology being developed by
scientists at Philips Research continues to utilize
the contrast-enhancing capabilities of microbubbles
to help ultrasound operators to locate tumors –
based on their density and the fact that tumors
typically grow a recognizable network of small blood
vessels around themselves. What’s new is that it
then shatters the shells of the microbubbles in
these blood vessels using a focused high-energy
ultrasound pulse. As a result, the drugs contained
in the microbubbles are released directly inside the
tumor.
Philips is working with several academic partners,
including the University of Virginia (USA) and the
University of Muenster (Germany), to refine the
technology. Clinical institutions, such as The
Methodist Hospital in Houston (USA), are also
actively researching this new and exciting field of
ultrasound mediated drug delivery.
“More and more, patients are demanding treatment
options that allow them to maintain their quality of
life during the treatment regime, without
sacrificing treatment efficacy,” comments King Li,
MD, Chair of the Department of Radiology at the
Methodist Hospital in Houston (USA) and Professor of
Radiology, Weill Cornell Medical College (USA). ”The
non-invasive nature of ultrasound mediated delivery
is a step in this direction. Work at our and other
institutions using ultrasound for drug delivery and
treatment guidance has shown the potential of this
technology in pre-clinical studies.”
|
