Medical Device Daily Washington Editor
WASHINGTON – Imagine polymers and cells engineered to come together and create almost any kind of medical device within the body.
“It may sound like science fiction but we are working on ideas to actually do it,” said Robert Langer, ScD, the Kenneth Germeshausen Professor of Chemical and Biomedical Engineering at the Massachusetts Institute of Technology (Cambridge, Massachusetts).
Langer addressed an auditorium filled with FDA staff and other members of the scientific and medical communities during last week’s 11th FDA Science Forum held at the Washington Convention Center.
With a career spanning more than 30 years, Langer has been involved with much of the cutting-edge research that has lead to some of the most recent revolutionary drug and device therapies.
When he received his doctorate in 1974, Langer said all his fellow graduates were getting high-paying jobs working for oil companies during the height of the energy crisis.
“To me that really wasn’t all that exciting,” he said. “I had a dream that we could do something with chemistry and engineering that would improve people’s health.”
Langer was one of the early pioneers in large-molecule drug-delivery systems.
“Back then there were no drug-delivery products,” he said. “Now this is an area that is thriving. There are probably 30 million to 40 million people in the U.S. that use drug-delivery products every day.”
Some of his work led to the development of patches that adhere to the skin to deliver controlled doses of medication, which are commonplace today, for birth control, smoking cessation, treating advanced prostate cancer and endometriosis.
He said conventional wisdom in the 1970s was that trying to get large molecules through polymer would be “like going through a brick wall.”
“I spent years in the lab experimenting and found over 200 different ways to get this to not work,” he joked. “Finally I found one, and one is all you need.”
One of the biggest breakthroughs in interventional cardiology developed in recent years is the drug-coated stent, which combine polymers and pharmaceuticals to combat coronary artery restenosis. It is a result of the same research.
Now, Langer and his colleagues are taking the technology a step further. He is working on drug-delivery systems on small, implantable microchips.
Still in early animal testing, these chips would incorporate drugs within small wells on chips made of bio-degradable polymers.
The wells, covered in gold, would be triggered in different ways to release their contents.
“What we are really hoping for in the future is to develop smart systems where someone would have an implantable patch and then a wristwatch that would have a program that could trigger the chip by remote control,” Langer said. “Using radio frequency telemetry and microelectronics, you could open any of the wells.”
He said that such chips even could be programmed to respond to react to direct input from the human body – such as the ability to detect certain molecules that would then trigger a therapeutic response from the chip.
The technology even could be used to help people keep track of the times drugs were taken. The chip, according to Langer, also could communicate its data to a home computer, a doctor’s office, or pharmacy to become part of an electronic health record.
Tissue engineering is another area that he is working on. “There are 30,000 patients a year in the U.S. waiting for a liver transplant and there are only enough for 3,000 patients,” he said.
Cells from a patient, a close relative, or even highly controversial embryonic stem cells could be used to grow tissues within the body on a polymer “scaffolding,” Langer said. After a time, the scaffolding would dissolve within the body and liver cells would be synthesized.
The same technology is being applied to spinal cord injuries, artificial skin and for creating cartilage. He said the cartilage currently developed is not strong enough for weight-bearing problems – which would be needed for orthopedic uses. He said it is strong enough for cosmetic needs, such as with burn victims or for patients with deformities.
Materials could even be created that respond to body temperature. “That’s even farther out there, but it is possible and we’re doing it in the lab now,” Langer said.
He said polymers and cells could be combined to have one shape at room temperature, but once exposed to the higher body temperature would take their preprogrammed shape, such as a coil, a vessel or even an implantable suture that ties itself.