Exactly one drug has been approved to delay the development of type 1 diabetes. Its name is teplizumab (Tzield). When given to people with presymptomatic type 1, it slows down the progression toward full-blown diabetes by an average of three years.
There’s only one problem: Hardly anyone knows when they have presymptomatic type 1 diabetes. Type 1 diabetes is customarily diagnosed only after the symptoms of hyperglycemia — including excessive thirst, frequent urination, and blurred vision — have become impossible to ignore. A sizable minority of Americans are diagnosed only after they have developed diabetic ketoacidosis (DKA) , a severe and potentially lethal condition with even more severe symptoms. Tzield can help only when type 1 diabetes has been identified with an autoantibody test long before any such symptoms emerge.
At the moment, however, the medical establishment pays very little attention to type 1 diabetes screening or presymptomatic testing. A recent American Diabetes Association (ADA) press release referred to the adoption of Tzield as “an uphill battle … because of a lack of awareness around screening and staging of type 1 diabetes.”
Last month, the ADA released updates to Standards of Care in Diabetes intended to help address the problem. The new recommendations push for more type 1 diabetes screening and officially validate Tzield as a therapy for people with presymptomatic type 1 diabetes. The update could help lead to a significant change in the way that type 1 diabetes risks are evaluated, enabling doctors to find more individuals who could benefit from Tzield.
What Is Tzield?
Tzield was created decades ago, initially as an immunosuppressant. Researchers soon learned that it was especially effective at suppressing the specific T-cells known to attack the pancreatic beta cells that are eliminated in type 1 diabetes. It has been developed as a diabetes therapy by ProventionBio, a biopharmaceutical company wholly dedicated to the prevention of autoimmune diseases.
When given to patients known to carry the antibodies that cause type 1 diabetes, Tzield delays the onset of symptoms by an average of nearly three years. For some lucky users, the benefits may be even longer-lasting. Some of the volunteers for ProventionBio’s earliest trials were found to be diabetes-free eight years after the initial treatment.
When type 1 diabetes develops in people at older ages, it’s associated with greater residual insulin production and a lower risk of complications. Tzield could also give families valuable time to prepare — months or years to learn about the condition and what to expect.
Tzield is administered by intravenous infusion, once daily for 14 consecutive days. There’s no follow-up treatment; those 14 days can create years of benefits.
What Is Presymptomatic Diabetes?
Experts delineate three stages of type 1 diabetes development:
Islet cell autoimmunity, characterized by the presence of autoantibodies. During this stage, blood sugar levels are still normal and the patient experiences no symptoms.
Early beta cell destruction. The decrease in beta cell mass reduces insulin production and results in slightly elevated blood glucose levels. The patient will still not experience any symptoms.
Full-blown type 1 diabetes. At this stage, beta cell mass is so low that the patient will experience overt hyperglycemia accompanied by the clinical symptoms of diabetes. Treatment with exogenous insulin will soon become necessary.
The first and second stages of diabetes development are presymptomatic.
Though stages 1 and 2 entail zero symptoms, they can be identified by antibody testing, a simple blood test that can confirm the presence of the cells that cause the autoimmune attack that defines type 1 diabetes.
Stage 2 can also be found when a routine blood test shows higher-than-expected blood sugar levels. A diagnosis can then be confirmed with antibody testing.
Screening for Type 1 Diabetes
Some experts believe that we should be screening all children for type 1 diabetes risk. As the updated Standards of Care in Diabetes notes, autoantibody screening programs “enable earlier diagnosis and prevent DKA.”
Until recently, there has been relatively little push to screen children for diabetes antibodies because there has been no validated way to slow down the disease’s onset. For the small number who have learned through antibody testing that they have an extremely high likelihood of developing type 1 diabetes, there’s little to do but keep watch for the development of hyperglycemia.
The existence and availability of Tzield fundamentally change that factor; now there is an unambiguous medical reason to conduct more screening.
Several pilot programs have been established to determine whether it is cost-effective to screen the general population. But it will take time before Tzield changes the way that the medical system operates. In particular, insurers and healthcare organizations may not be eager to cover the cost of targeted autoantibody screening, let alone screening the general population.
In the meantime, screening will undoubtedly first gain popularity in families with a history of type 1 diabetes. Type 1 diabetes has a strong genetic component. According to a 2018 study, the siblings of individuals with type 1 diabetes, for example, are about 15 times as likely to develop the condition as someone without a family history. The children of a mother with type 1 diabetes are three to 10 times more likely to develop the disease; when the father has type 1 diabetes, the children are 15 to 20 times as likely.
There are now several organizations that offer autoantibody screening, sometimes at no cost. The charity JDRF curates a list of resources. TrialNet is one option popular within the diabetes online community.
Who Can Use Tzield?
According to the ADA’s new recommendations, Tzield can be used in patients over the age of 7 with stage 2 type 1 diabetes. These are patients that have not experienced symptoms of hyperglycemia but for whom both autoantibody tests and blood sugar measurements confirm the presence of developing type 1 diabetes.
Takeaways
The new drug Tzield can delay the onset of type 1 diabetes symptoms in people who have already developed early asymptomatic cases of type 1 diabetes.
The American Diabetes Association, the country’s most influential diabetes organization, has now validated the use of Tzield and endorsed the case for more aggressive screening for the autoantibodies that predict the onset of type 1 diabetes. There is hope for increased awareness and screening efforts to identify individuals at risk and provide them with the benefits of this groundbreaking treatment.