Helping the meds go down
In addition to dreaming up higher-tech pills, scientists are also working on drug delivery approaches that don’t go the oral route. There is a reason for that: Many innovative drugs don’t work as pills.
New drugs made out of proteins -- for conditions such as cancer and arthritis -- would simply be digested if they were to land in the stomach. Instead, patients must receive the medicine as injections or infusions so it directly enters the bloodstream. Researchers hope to replace the uncomfortable, time-consuming needle-based treatments with drug pumps that are easier and less painful for patients to use.
MicroChips Inc. of Bedford, Mass., is working on an implantable pump for delivery of one such protein-based medicine, human parathyroid hormone. Marketed as Forteo, it’s the only drug that can actually rebuild bone in women with osteoporosis.
“The problem is you have to inject it daily for two years,” says Maggie Pax, vice president of business development at MicroChips. She estimates that more than half of women give up on the treatment within the first year because of the hassle.
MicroChips’ solution is a chip containing hundreds of tiny, sealed wells, each holding one dose of dried-up hormone. An electrical signal from an onboard battery pops the top of one reservoir per day, releasing the drug.
An early design of the chip measured approximately 1 by 2 inches, but Pax expects the final incarnation will be smaller. She envisions patients getting the device implanted abdominally during a quick outpatient procedure.
MicroChips plans to start a trial this month with 10 women who have osteoporosis to study how long the drug lasts in a person’s bloodstream, Pax says. She hopes the device will hit the market in a couple of years.
The company is also working on sensor-equipped implants that might, for example, recognize the signs of a heart attack and release a quick dose of nitroglycerin.
Other scientists are working on devices that deliver medicine to exactly where it’s needed. For example, Michael Cima, an engineer at MIT in Cambridge, Mass., has invented an implant that delivers a steady stream of medication to the bladder.
The standard way to treat bladder cancer or bladder pain is to provide the medicine via a catheter, but the benefits only last as long as the patient can, well, hold it. Cima’s device, now being developed by Taris Biomedical in Lexington, Mass., is a 0.2-inch-long silicone sausage. It goes in through a catheter, but once in the bladder it folds up like a pretzel so it can’t slip back down the urethra. The device releases drug continually until it’s removed, again via catheter.
The company has completed early studies to show the pretzel isn’t uncomfortable. “People can’t tell the device is in them,” Cima says. “It just floats in the bladder.” He estimates the product might be available in 2014.
“There’s all kinds of new things on the horizon for drug delivery,” Cima adds. For example, some people with diabetes have dumped the needle in favor of disposable insulin pumps they stick to their skin. Cima predicts the same technology will be applied to other drugs in coming years. Some drugs that people normally get in a hospital could be taken at home with such a pump.
Cima also predicts more drugs will be inhaled in the future, although manufacturers need to work out how safe it is to have proteins in the lungs and how well they travel to other organs.
