Researchers have developed a new microchip implant device that can deliver bone-building drugs to seven osteoporosis patients. The microchips worked inside patients as drug-delivering pacemakers, following a prescription plan sent by radio signal.
“This is equivalent to an injection without the pain or trouble ,” says study lead author Robert Farra of MicroCHIPS Inc., of Waltham, Mass, which makes the devices. Farra and colleagues presented the study, a “safety” trial of the devices , at the American Association for the Advancement of Science meeting in Vancouver. The work also appears in the journal Science Translational Medicine.
The team conducted surveys that showed that only about half of all patients fully follow prescription plans for all drugs. Only about 25% of the 50,000 osteoporosis patients nationwide who now take the implant trial hormone — which requires injections, refrigeration and can cost around $10,000 a year - continue taking it for the full two-year course. .
In the study, conducted in Denmark, surgeons implanted the microchips in the abdomens of seven women aged 65 to 70, in a 30-minute office surgery. Later, the implants received signals releasing doses of the drug from microscopic reservoirs etched in the chip, for up to 20 days. Doctors measured the drug's effects in blood samples, finding them similar to regular injections. Reassuringly, a collagen layer that grew to surround the implants didn't block the drugs from reaching the bloodstream.
Robert Neer, director of the Massachusetts General Hospital Bone Density Center and a co-author of the study, said the drug builds bone if given intermittently, but destroys bone if given continuously, making programmable dosing an advantage. The active ingredient of teriparatide is hermetically sealed in powder form in tiny wells on the chip. An electric current is fired in the chip to release the medicine.
Immediately after implantation it became evident that the device was not working in one patient, and it was removed. An analysis of the remaining seven patients confirmed that the microchip delivered the osteoporosis drug in comparable doses to daily injections with no unwanted side effects. The women reported that they could not feel the devices and expressed a preference for the implanted microchip over daily injections for future treatment.
“This is the first successful human study of an implantable, wireless microchip that provides 100% treatment compliance and frees patients from the burden of managing their disease on a daily basis,” Farra said. “This is a really interesting delivery system, one that has some real potential,” says osteoporosis expert E. Michael Lewiecki of the University of New Mexico School of Medicine in Albuquerque, who was not part of the study.
“Our next goal is for a chip that can deliver daily doses for 365 days,” Farra says. If successful, the implants would receive federal approval for medical use after 2016. The implants would likely cost as much as injections.
MIT professor of engineering Michael J. Cima, originally developed the idea for a programmable drug-delivery microchip more than a decade ago, along with colleague Robert Langer. Cima says the technology could potentially be useful for delivering any potent drug or even multiple drugs, with the benefit of improving patient compliance. “Patient compliance is a big issue, especially when we are asking patients to give themselves daily injections of a drug,” he tells WebMD. “This could take patient compliance out of the equation.” And because the devices can be controlled remotely, physicians and patients can change dosing as needed. “You could literally have a pharmacy on a chip,” Langer said in a news release.
Mark Salzman, a biomedical engineer at Yale University who wasn't involved in the study, said the findings underscore the potential for merging drugs and devices in medicine. “It's really difficult to design a delivery system that gives you the ability to control release of a drug over time,” he said.
Henry Brem, professor of neurosurgery, ophthalmology, oncology and biological engineering at Johns Hopkins University School of Medicine, called the results “stunning.” “It’s very rare to find a paper that is really a breakthrough in technology,” says Brem, who was not part of the research team. “It fulfills the promise of polymer drug delivery and the incredible sophistication of microchip capabilities.”
University of California, San Diego professor of bioengineering John T. Watson, calls the 20-dose trial an important first step in showing that a programmable drug-delivery microchip is possible. But he tells WebMD that many years and hurdles remain before the technology reaches the clinic. In an editorial published with the study today in the journal Science Translational Medicine, Watson writes that although the road may be long and winding, “a versatile, implantable device that exploits the microchip approach for controlled drug delivery will be worth the wait for patients with chronic diseases.”
The study was funded and overseen by MicroCHIPS Inc. In addition to osteoporosis, the company sees potential for the device in treating multiple sclerosis and chronic pain in certain patients.