Teplizumab Approved by FDA to Delay Type 1 Diabetes

The FDA Thursday approved teplizumab, the first drug to delay the onset of type 1 diabetes (T1D). Teplizumab, a biologic, will be sold under the brand name Tzield and is given through intravenous infusion once daily for 14 consecutive days.

It is approved for adults as well as children aged 8 and above.

Teplizumab aims to prevent the progression of T1D from stage 2—when metabolic abnormalities are seen—to stage 3, when clinical symptoms of T1D are seen. It is an Fc receptor–nonbinding anti-CD3 biologic that binds to certain immune system cells and deactivates them from attacking insulin-producing pancreatic beta cells, while increasing the proportion of cells that help moderate the immune response.

Stage 2 T1D is linked with a nearly 100% lifetime risk of progression to clinical T1D and a 75% risk of developing the condition within 5 years.

Safety and efficacy were evaluated in a randomized, double-blind, event-driven, placebo-controlled trial with 76 patients, most of whom were 18 years of age or younger, with stage 2 T1D. Results of that study were published in the New England Journal of Medicine in 2019.

In the trial, patients randomly received teplizumab or a placebo; the primary measure of efficacy was the time from randomization to development of full-blown T1D.

Over a median follow-up of 51 months, 45% of the 44 patients who received teplizumab were later diagnosed with T1D, compared with 72% of the 32 patients who received a placebo.

The mid-range time from randomization to T1D was 50 months for the patients who received teplizumab and 25 months for those who received a placebo.

According to a published report, teplizumab will have a wholesale cost of roughly $194,000 for a full course of treatment.

Approval was granted to ProventionBio, which is co-promoting the drug with Sanofi. The drug received Priority Review and Breakthrough Therapy designations for this indication. An FDA advisory panel voted 10-7 in favor of the drug last year; Provention Bio subsequently received a complete response letter with some questions about the study's size and general manufacturing concerns.

The use of teplizumab comes with warnings and precautions about premedicating and monitoring for symptoms of cytokine release syndrome; risk of serious infections; decreased levels of lymphocytes; risk of hypersensitivity reactions; the need to administer all age-appropriate vaccinations prior to starting therapy; and avoiding concurrent use of live, inactivated, and mRNA vaccines with teplizumab.