SCIENTISTS USE WIRELESS MICROCHIPS TO CONTROL DRUG RELEASE IN VIVO
Bedford, MA - March 13, 2006 - Researchers at MicroCHIPS, Inc., have demonstrated for the first time that it is possible, using an implanted, microchip device and wireless technology, to actively control the release of drugs in the body over a prolonged period of time.
"This research is an important step toward development of novel drug delivery systems in which small devices filled with potent, therapeutic drugs are used to release medicines into the body as needed," said John Santini, PhD, president of MicroCHIPS.
The technology, described in the March 12 online edition of Nature Biotechnology (Santini et al; Chronic, programmed polypeptide delivery from an implanted, multireservoir microchip device; Nature Biotechnology 24, 437 - 438 (01 Apr 2006)), is unique in its use of wireless signaling, its system of reservoirs allowing precise, efficient delivery of solids, liquids or gels, and its small size. It is not expected to replace all pills or other forms of drug delivery. Rather, it will deliver proteins, small molecules and other drugs that are highly potent, have limited stability, and must be delivered in precise doses at specific times.
Santini, along with Massachusetts Institute of Technology Professors Robert Langer, ScD and Michael J. Cima, PhD, began work on the concept of so-called "intelligent drug delivery devices" more than a decade ago.
Langer, Institute Professor at MIT, called the current publication a "landmark" study. "One could envision that, some day, many of a patient's drugs could be placed on a chip programmed to release needed doses at precisely the right times," he said.
The Research
The scientists began the current research by developing microchips made of silicon, each the size of a postage stamp and containing 100 tiny "wells" or "reservoirs." According to James Prescott, PhD, Director of Analytical Chemistry at MicroCHIPS and co-lead author of the study, "We filled the reservoirs with a model polypeptide drug known to be poorly absorbed when taken orally. Each reservoir was capped with an electrically-erodable membrane made of platinum and titanium. Filled chips were then sealed and connected to a titanium case containing electronic hardware, power, and wireless connectivity. We also combined custom software with "off-the shelf" electronic components and a handheld wireless communication device for use in sending data back and forth." Finally, the scientists implanted chips beneath the skin of six canines.
According to Sara Lipka, Senior Engineer at MicroCHIPS and co-lead author, "For the first month, we used a wireless signal to simultaneously release the drug from 10 reservoirs once a week. For the next two months, we simultaneously released doses from five reservoirs once every two weeks. For the last three months of the study, we simultaneously released doses from four reservoirs once a month.
In this way, "we demonstrated that we could control the release of drugs in the body via a wireless device and that it was possible to do so for at least six months," Lipka said.
Reservoir Technology
The current study, which used a microprocessor and a power source, demonstrates the feasibility of what Santini calls "active" reservoir control. According to Santini, while one important use of reservoirs is to contain drugs for release, reservoirs can also be used to selectively expose biosensors in order to monitor and provide feedback on conditions in a patient's body. Biosensors may one day be interactively paired with drug delivery.
MicroCHIPS is also working on another type of reservoir technology, which Santini terms "passive." Passive reservoir systems use specially-designed, layered polymers which, when implanted, regulate drug release over time without microprocessors or power sources.
"Reservoir drug delivery systems should be especially useful if applied to congestive heart failure, diabetes, osteoporosis and orthopedics," Santini said.
MicroCHIPS plans to partner with pharmaceutical and medical device companies to identify "difficult-to-deliver" molecules that would be compatible with reservoir technology and to develop novel biosensors. In Santini's words: "Reservoir technology is unique in that it can provide the basis for a stand-alone, intelligent medical device unlike anything available on the market or it can provide market differentiation for an existing product when incorporated as a new feature."
If all goes as planned, "we could begin human safety trials for passive reservoir systems for drug delivery within three years and for active "sensing" systems in three-to- five years," Santini said.
The research, reported in "Chronic, programmed polypeptide delivery from an implanted multireservoir microchip," is scheduled for publication online at Nature Biotechnology on March 12 and in the April print edition of Nature Biotechnology.
MicroCHIPS is a privately-held, venture-backed company founded in 1999 by Cima, Langer, Santini, and Terry McGuire, Managing General Partner of Polaris Venture Partners. Major investors include Polaris Venture Partners, IDG Ventures, Intersouth Partners, Care Capital, and the Boston University Community Technology Fund. Corporate partners include Medtronic, Inc. and Boston Scientific Company.
http://www.mchips.com/06_Mar_13_pr.htm