Kriya Therapeutics KRIYA-839 (AAV insulin + glucokinase gene therapy)

Most cures in development replace the islet cells that type 1 diabetes destroys. Kriya Therapeutics is trying something different: skip the cells entirely and reprogram a tissue the disease never attacks — skeletal muscle. KRIYA-839 is an adeno-associated virus (AAV) gene therapy that delivers two genes at once: human insulin, and glucokinase, an enzyme that acts as a glucose sensor. Injected into the thigh muscles during a single outpatient visit, the muscle is meant to become a standing insulin factory that releases more insulin as blood sugar rises and stays quiet when it falls, with glucokinase providing the glucose-responsiveness.

The evidence so far is preclinical. In mouse and dog models of type 1 diabetes, a single treatment lowered blood sugar durably, with effects reported to last up to four years in animals. On that strength, Kriya announced the PROGRESS study — described as the first-ever AAV gene-therapy trial in type 1 diabetes — enrolling adults already using closed-loop pumps, with a 52-week follow-up for safety and effect on insulin use.

Important caveats: no human has been dosed in the public record, and the registry entry was not yet posted as of mid-2026. Open questions include how tightly muscle-made insulin can be controlled (hypoglycemia risk), how pre-existing AAV immunity limits who can be treated, and whether animal durability carries into people. If it works, the appeal is a one-time, cell-free, immunosuppression-free shot — but that remains unproven.