New materials technology - particularly with resorbable
compounds - is leading to significant advances in medical devices.
A drug-eluting absorbable metal scaffold was recently implanted
in the first patient by Dr. Michael Haude in Neuss, Germany. Most absorbable
stents developed to date have been made from polymers.
Developers of the new technology say that the magnesium
metal alloy provides mechanical advantages over plastics, while providing a
reliable degradation profile in which it slowly returns to its natural
The new device is combined with a slow-release drug and is
intended to open vessels and to keep them from reclogging, while avoiding the
longer-term disadvantages associated with permanent metal stents such as "late
The safety and biocompatibility of bare magnesium scaffolds
have been proven in previous Biotronic studies.
A global pioneer in absorbable magnesium, Biotronic says it has refined this
technology for more than 10 years based on physicians' input to deliver the
optimal balance between vessel scaffolding, degradation profile and drug-elution
"DREAMS (drug-eluting absorbable metal scaffold) is
different than a drug-eluting stent because it offers a promising solution for
currently unmet clinical needs," says Alain Aimonetti, vice president marketing
and sales with Biotronic. "Many physicians anticipate that the absorbable
aspect will initiate a true revolution in interventional cardiology."
Metals typically use for stents have been nickel titanium alloy
(nitinol), cobalt chromium, titanium, tantalum or steel, such as 316 L.
Another interesting materials' development comes from InVivo Therapeutics
MA, whose MIT-developed polymer technologies provide a novel approach to the
treatment of spinal cord injuries.
A resorbable polymer-based medical device is used for the
repair of spinal cord tissue for open- and closed-wound spinal cord injuries. Dr.
, institute professor
at MIT, and Dr. Yang (Ted) Teng of Harvard's Neurosurgery Dept. said in a
research study: "We have designed an implant modeled after the intact spinal
cord consisting of a multi-component polymer scaffold."
At 70 days post-injury, animals implanted with scaffold plus
stem cells exhibited coordinated, weight-bearing hind limb stepping. Analysis
suggested that this recovery may have been due to a reduction in tissue loss
from secondary injury processes as well as in diminished glial scarring.
InVivo Therapeutics has worked with MIT professors to
commercialize the technology, and hope to begin a human trial in the next few