Creams or patches to control diabetes: this is the tool that aims to replace needles

BarcelonaResearchers at Imperial College London and Zhejiang University (China) have created a polymer—a large molecule—that allows insulin to be applied to the skin as a cream or patch, penetrate the skin barrier, and reach the bloodstream without a needle. The research, published in the journal NatureIt has been tested in mice and pigs, and its developers propose it as a future alternative to insulin injections for diabetes management.

The skin is a very strong barrier, and insulin cannot penetrate the outermost layer. Therefore, patients depend on daily injections, a process that often causes pain, fear, and poor treatment adherence. Researchers have demonstrated that the polymer, called OP, is capable of transporting insulin through the skin quickly and non-invasively, taking advantage of a biological feature: the skin's natural pH gradient.

To put it simply, this new tool is able to change its behavior depending on its location. In the outermost layer of the skin, which is more acidic, the polymer attaches using lipids (fats), and as it moves down the layer, it becomes neutral and can glide like soap to penetrate deeper layers. Once in the dermis, it infiltrates through the lymphatic capillaries and from there travels into the bloodstream, which distributes insulin throughout the body.

Human trials are needed

In pigs and mice, researchers confirmed that insulin bound to the polymer reduced glucose levels as quickly as an injection, with a prolonged effect lasting around 12 hours. However, human trials are needed to confirm its safety and efficacy before it can replace insulin injections.