About 30,000 people are diagnosed with type 1 diabetes every year in the United States, and it is one of the most common chronic diseases in American children. Type 1 diabetes is typically diagnosed in childhood, but it's a lifelong condition that requires constant monitoring. It typically occurs when the immune system mistakenly attacks the cells in the pancreas that produce insulin, called beta cells. Since insulin helps regulate blood sugar levels, this causes abnormally high levels of glucose in the blood. People with diabetes have to constantly monitor their condition, which can significantly impact their quality of life.
Now the US Food and Drug Administration (FDA) has approved the first drug that can delay the onset of diabetes, called teplizumab, which is made by Provention Bio; the drug will be marketed and sold as Tzield. People who take the medication will have to get a daily infusion for two weeks. The drug can delay the onset of diabetes by two years or more. It's a monoclonal antibody that alters T cells so they won't attack beta cells; it targets a component of T cells called CD3, which has been tested as a diabetes treatment for decades.
While researchers understand how the anti-CD3 antibody targets T cells, we still don't know a lot about how it modulates the immune system. CD3 is one part of the T cell receptor (TCR) complex that is found on T cells. TCR signaling is complex, but scientists have found that anti-CD3 antibodies like teplizumab can prevent some of the toxic effects caused by T cells. Many trials have shown that anti-CD3 antibodies can delay the onset of diabetes if the dosage is optimal and the medication is delivered before or soon after the onset of disease.
The latest clinical trial of teplizumab was a double-blind study in which 76 people with stage 2 type 1 diabetes were given either the drug or a placebo once a day through an IV infusion for two weeks. The aim was to prevent or delay stage 3 type 1 diabetes. Researchers found that after a median time of 51 months, 45 percent of those who got the drug were diagnosed with stage 3 type 1 diabetes, while 72 percent of those who got a placebo got the diagnosis.
The onset of disease took about twice as long in people who got the drug - the middle of the range of stage 3 type 1 diabetes diagnosis time was 25 months for people getting a placebo, and 50 months for those who got teplizumab. Common side effects included rash, headache, and lower levels of some white blood cells. Vaccines also have to be used prior to the treatment or under a doctor's direction because of the drug's effect on the immune system.
"People with diabetes will tell you that any time without the disease is a gift, particularly for young children and their parents. Some ask, 'If you're still going to get diabetes, what's the big deal?' But when you're an eight-year-old child, if the time at which you need to take insulin, follow a prescribed diet, and monitor your blood sugar is delayed for two more years, that's huge," noted principal study investigator Kevan Herold, MD, a Yale Medicine endocrinologist.
Older kids may also be better at performing the daily tasks associated with the disease. The drug has also been effective for a very long time in some people. One high school student in the trial was free of diabetes for eleven tears after teplizumab treatment, said Herold.
This is also a first step on the road to preventing the disease completely, or restoring the cells that are lost to autoimmunity, added Herold.
Teplizumab or Tzield has now been approved by the U.S. Food and Drug Administration for patients who currently have stage 2 type 1 diabetes, and are older than 8 years of age.
Sources: Yale Medicine, FDA
