The antibody teplizumab slows the destruction of the cells in the pancreas that produce insulin in children and adolescents who begin to have symptoms of type 1 diabetes, the most severe form of the disease. But its effectiveness in controlling the level of sugar in the blood and in reducing the need to inject insulin is modest, so the usefulness that the drug will end up having in the treatment of diabetes is still uncertain.
These are the main conclusions of the Protect clinical trial, in which 328 patients from Europe and North America participated. were presented yesterday in The New England Journal of Medicine and at the International Society of Pediatric and Adolescent Diabetes congress held in Rotterdam.
“It is an advance that indicates that we are going in the right direction to improve the treatment of diabetes, acting on the immune system”, says Jesús Blanco, specialist in endocrinology and nutrition at the Clínic hospital.
“A new era is opening in the treatment of diabetes. For the first time we have a therapy capable of modifying the course of the disease”, declared in the same line the endocrinologist Chantal Mathieu, president of the European Association for the Study of Diabetes, in a press conference from Rotterdam.
Type 1 diabetes, which is usually diagnosed in childhood or adolescence, is a chronic disease that can evolve into cardiovascular, kidney, nervous system and retinal problems. It is different from the more common type 2 diabetes, which is usually diagnosed in adults.
There were high expectations for teplizumab, an immunosuppressive drug that reduces the immune system’s attack on the beta cells of the pancreas. The destruction of these cells is what prevents people with type 1 diabetes from being able to control their blood sugar levels by themselves, so they need to inject themselves with the hormone.
In a previous study, teplizumab slowed the progression of diabetes in children diagnosed early, before the onset of symptoms. This result led to the drug being approved last November in the US for this type of patient. It is expected that it will also be approved in Europe in the coming months.
But it needed to be clarified whether teplizumab can slow the progression of diabetes when the first symptoms have already appeared and there are fewer beta cells left to save in the pancreas. This is the unknown that the Protect study had to clarify, in which recently diagnosed minors aged between 8 and 17 took part.
A year and a half after the start of treatment, 95% of patients treated with teplizumab maintain an adequate level of C-peptide, which indicates adequate insulin production. Among patients given a placebo, the percentage drops to 79%, and this reflects a faster degradation of insulin-producing cells.
Demonstrating a significant reduction in C-peptide levels was the primary goal of the study, and it was met, paving the way for teplizumab to be approved to treat children and adolescents after the onset of symptoms.
But the improvements observed in the secondary objectives of the study were not statistically significant. The percentage of time that an adequate level of glucose in the blood is maintained is 68.6% in patients treated with teplizumab and 64.6% among those who have received placebo. And the number of major episodes of hypoglycemia is 4.66 per year if teplizumab has been received and 4.39 if placebo has been received.