Crispr gene-editing technology has demonstrated its revolutionary potential in recent years: It has been used to treat rare diseases, to adapt crops to withstand the extremes of climate change, or even to change the color of a spider’s web. But the greatest hope is that this technology will help find a cure for a global disease, such as diabetes. A new study points in that direction.

For the first time, researchers succeeded in implanting Crispr-edited pancreatic cells in a man with type 1 diabetes, an autoimmune disease where the immune system attacks insulin-producing cells in the pancreas. Without insulin, the body is then unable to regulate blood sugar. If steps aren’t taken to manage glucose levels by other means (typically, by injecting insulin), this can lead to damage to the nerves and organs—particularly the heart, kidneys, and eyes. Roughly 9.5 million people worldwide have type 1 diabetes.

In this experiment, edited cells produced insulin for months after being implanted, without the need for the recipient to take any immunosuppressive drugs to stop their body attacking the cells. The Crispr technology allowed the researchers to endow the genetically modified cells with camouflage to evade detection.