November 2022 was a historic moment for the type 1 diabetes (T1D) community: Teplizumab (Tzield), the first disease-modifying therapy (DMT) for T1D, was approved by the FDA.
Tzield has been game-changing for T1D. It’s the first therapy for the disease that addresses the root cause of T1D, not the symptoms. It targets the T cells that are responsible for destroying insulin-producing beta cells, slowing down the autoimmune processes that cause T1D. Tzield has proven to delay progression to Stage 3 T1D—when insulin therapy is often required—for up to three years.
The approval of Tzield was a culmination of decades of passionate work by Breakthrough T1D, the only organization that supports T1D therapy development at every stage—from discovery research all the way through to people with type 1 diabetes receiving these therapies with healthcare coverage paying for them.
Pioneering Research and Strategic Investments
In the late 1980s, Kevan Herold, M.D., had just started his faculty-level career at The University of Chicago. He was diagnosed with T1D several years earlier, which heavily influenced his decision to focus on endocrinology. There, he met Jeff Bluestone, Ph.D., an immunologist concentrating on cancer research. After meeting many members of the T1D community through Dr. Herold, Dr. Bluestone switched a large portion of his research to new therapies for T1D.
One of their early studies showed that type 1 diabetes onset could be delayed with an anti-CD3 antibody, which later became teplizumab. Breakthrough T1D supported this novel research, which led to the first-ever clinical trial of a T1D disease-modifying therapy in humans in the early 2000s. The trial was a success and laid the groundwork for further studies and eventual support from the National Institutes of Health (NIH) through the Special Diabetes Program (SDP).
Over the next two decades, teplizumab was acquired by MacroGenics, a company formed to develop immune-based therapeutics for autoimmune diseases and cancer, then sold to Provention Bio, a T1D Fund-backed biopharmaceutical company focused on disease interception and prevention. The drug underwent several NIH and Breakthrough T1D-funded clinical trials; it was Provention Bio’s PROTECT trial that pushed it over the finish line to FDA approval in 2022.
In 2023, Provention Bio was acquired by Sanofi. This brought the first T1D disease-modifying therapy into the portfolio of a leading global pharmaceutical company. It also represented a significant endorsement of the potential of DMTs to have an impact on people living with T1D.
People like Chris Dunn.
Breakthroughs in Action
Chris Dunn is a parent of four children, two of whom live with T1D. Knowing that immediate family connections are a risk factor for developing T1D, Chris and her children without T1D participated in screening.
Much to her surprise, Chris’ screening results revealed the presence of multiple T1D antibodies; further testing indicated she was in stage 2. Chris knew that Tzield could potentially delay her need for insulin therapy, so she made the informed decision to undergo treatment.
“I’ve had a front row seat to this disease for nearly 20 years,” Chris said. “Any day that you can save yourself from having to be on insulin therapy and all of the risks that come with that is worth it to me.”
Chris represents our research breakthroughs in action. She hopes that Tzield will delay the onset of Stage 3 T1D until cell therapies are available to cure the disease.
The Future of Tzield
As Tzield becomes more widely used in people over the age of 8 in Stage 2 type 1 diabetes, Breakthrough T1D’s Disease-Modifying Therapies Program is exploring how it may benefit other ages and stages.
“We continue to fund research to discover and develop new interventions and new ways of rebalancing the immune system, ultimately working toward our goal of a world without type 1 diabetes,” said Joshua Vieth, Ph.D., Senior Director of Research at Breakthrough T1D.
In October 2025, Tzield was accepted into the FDA Commissioner’s National Priority Voucher program for accelerated review. If approved, this could lead to expanded use of Tzield for people with newly diagnosed Stage 3 T1D (when insulin therapy is required). This is significant—it would be the first time people at this stage could have the option for a disease-modifying therapy.
Delaying the onset of T1D in young children would be transformative for families facing a diagnosis. Interim results from an ongoing clinical trial, PETITE-T1D, showed that Tzield is safe and well-tolerated in children under 8 with Stage 2 T1D. Final results of the study are expected sometime this year, and Tzield has been accepted for priority review by the FDA for this population.
While Tzield is the first approved disease-modifying therapy for T1D, Breakthrough T1D will make sure it’s not the last. Our goal is to not just delay T1D progression but stop it entirely, or even reverse its course. We will support the continuous development of these therapies to change the trajectory of type 1 diabetes for everyone affected by it—and those yet to be—to cure the disease.
