New Implants Could Treat Type 2 Diabetes Without Needles

Implants that deliver a constant metered dose of medication have plenty of promise. They’re especially useful for making sure patients don’t have to orient their daily schedule around their medication times. For the same reasons, they’re a potential solution for patients who tend to forget to take medications that have to be delivered right on schedule. Their major strength is being able to keep a patient’s serum concentration of their medication at a specific level.

For example: Nexplanon, a hormonal contraceptive implant, delivers a constant dose of medication that keeps a woman’s progesterone levels within a particular range that prevents her from ovulating. Too high or too low a dose, and everything would get out of whack. But the implant keeps the serum concentration pretty stable.

But because of the steady diffusion of the active substance, such drug-delivery implants aren’t fabulous for conditions that require medication only when symptoms appear. There hasn’t been a lot of luck with an implant for asthma, for example, because we haven’t surpassed the rescue inhaler for timely asthma treatment. Another condition that has resisted the implant approach is type 2 diabetes. Because type 2 is all about insulin insensitivity, and insulin is something that operates in a tight feedback loop with fluctuating blood glucose levels, you don’t necessarily want a blood insulin concentration that’s always held stable at the same level.

Monitoring Blood Chemistry in Real Time

Not to worry, though: the biotechnologists are on this. Scientists are developing implantable biomedical microelectromechanical systems (bioMEMS) that can monitor your blood chemistry in real time, deliver timed and quantized doses of medication, and phone home to your doctor to report on what they’ve done.

Currently people with type 1 diabetes have the option to get an implanted insulin pump that can deliver insulin on demand, so they don’t have to stab themselves every time they need insulin. You may have seen these — they clip to a person’s belt and look a little like a pager. But type 2 diabetes is more related to insulin insensitivity than it is to failure to produce insulin in the first place. Some diabetics can manage their disease through diet alone, and others take metformin by mouth, while more severe cases can become insulin-dependent. Insulin demand changes along with blood sugar and activity levels.

Intarcia diabetes

Credit: Intarcia

Successfully managing type 2 diabetes with an implant necessitates real-time monitoring of blood chemistry, and quantized dose delivery. So scientists have been attacking this problem from multiple angles.

Real-time blood chemistry analysis happens via an implanted lab-on-chip (LOC). These tiny but promising devices are around the size of your thumbnail, but their capabilities are huge. From where they’re implanted in well-vascularized connective tissue, they take a continuous account of blood chemistry and perform basic analysis to report what your likely insulin demand will be. Wired UK reports one such LOC capable of monitoring for five separate biomolecules — it’s inductively charged by a battery pack worn outside the skin, and it can report its results via Bluetooth.

As for drug delivery, in November 2016 a company called Intarcia filed for marketing approval with the FDA, in order to market an implantable drug delivery pump (above right) for type 2 diabetes. It would need replacing to “top up” its proteins once or twice a year. But the rest of the time, it would deliver timely doses of a drug called exatenide that beat another big-name diabetes medication, sitagliptin, in clinical trials.

Now, the biomedical sciences are just as riddled with startups that overpromise and underdeliver as any other industry. But we hate vaporware just as much as you do, which is why we’re even talking about this thing. It’s solid enough that the Bill and Melinda Gates Foundation has invested in the project; there’s a version of the implant that can also be used for HIV medications. If they get FDA approval, Intarcia hopes to release the implant in late 2017.

The combined powers of real-time analysis and metered drug delivery present a tantalizing possibility of real relief for type 2 diabetics, especially in difficult cases where blood chemistry just doesn’t want to behave. Minding diabetes at home is a laborious and often painful process involving careful time and calorie management, and sometimes needles. But it might not have to be all needles much longer.

Image credit, top: Intarcia

Let’s block ads! (Why?)

ExtremeTechExtreme – ExtremeTech