PHOTODYNAMIC THERAPY: Photoswitchable drug may increase safety of type 2 diabetes treatment

Type 2 diabetes mellitus affects 1 in 12 adults worldwide, and a class of drugs called sulfonylureas are a mainstay of diabetes therapy. While sulfonylureas are effective and relatively inexpensive, they have unhappy side effects—for example, they can provoke prolonged episodes of low blood sugar, elevate cardiovascular disease risk, and induce weight gain. Now, researchers at Imperial College London (England) and Ludwig Maximilian University of Munich (Germany) have developed a light-sensitive sulfonylurea that could be inactive under normal conditions, and activated by a patient using LEDs stuck to his/her skin.¹ Only a small amount of light would need to penetrate the skin to trigger the drug, which switches off when the light goes out.

Using in situ imaging and hormone assays, the researchers have shown that JB253 works on pancreatic beta cells of both rodents and humans. Although the current activation wavelength of 400–500 nm limits deep tissue penetration, the research team has begun to develop variants that can be switched at longer wavelengths. According to David Hodson of Imperial College's Department of Medicine, one of the leaders of the work, "So far, we've created a molecule that has the desired effect on human pancreatic cells in the lab. There's a long way to go before a therapy is available to patients, but this remains our ultimate goal." He noted that this type of therapy may allow better control over blood sugar levels because it can be switched on for a short time when required after a meal. It should also reduce complications by targeting drug activity to where it's needed in the pancreas.

1. J. Broichhagen et al., Nat. Commun., doi:10.1038/ncomms6116 (2014).