The US Food and Drug Administration (FDA) has declined to approve the anti-CD3 monoclonal antibody teplizumab (Tzield, Provention Bio) for the delay of type 1 diabetes in at-risk individuals, despite narrow endorsement in a 10-7 vote in favor of approval by one of its advisory panels in May.
According to the company, the FDA did not cite any clinical deficiencies related to the efficacy and safety data packages submitted as part of the biologics license application for teplizumab.
Rather, the sticking point appears to be a study in healthy volunteers that had been raised as an issue with Provention Bio in April.
That study was designed to compare the planned commercial product with the product originally manufactured for clinical trials, but the former was not pharmacologically comparable to the latter, the FDA said in its complete response letter, issued on July 2.
The company expects later this quarter to obtain data from a substudy in patients receiving 12 days of therapy in the ongoing PROTECT trial of newly diagnosed patients with type 1 diabetes, which it hopes will help alleviate the FDA’s concerns.
“Upon review of the results from this substudy, the company will determine whether to submit these data to the FDA for its review…to support pharmacokinetic comparability or otherwise justify why pharmacokinetic comparability is not necessary,” it said in its statement.
The FDA’s complete response letter had also mentioned additional issues related to product quality that Provention believes it has or will be able to address in the short-term.
Teplizumab Delays Type 1 Diabetes Onset by Years
Phase 2 data showing that a 14-day teplizumab infusion delayed the onset of type 1 diabetes by 2 years in high-risk relatives of people with the condition were called “game-changing” when presented at the American Diabetes Association 2019 Scientific Sessions and simultaneously published in the New England Journal of Medicine. These were the data considered by the FDA advisory panel in May.
In response to the FDA decision, the type 1 diabetes research and advocacy organization JDRF said: “It is unfortunate that the FDA has not approved teplizumab at this time and instead has requested additional information from the sponsor. We look forward to Provention Bio Inc addressing the issues outlined in the Complete Response Letter and working with the FDA to bring this option to market safely.”
Teplizumab is one of several potential disease-modifying therapies being studied for type 1 diabetes administered either soon after diagnosis or to asymptomatic individuals with high-risk autoantibodies.
“Disease-modifying therapies such as teplizumab will help address the unmet needs of people with type 1 diabetes and those at risk for developing the disease. In the meantime, our organization will continue to support the research of other disease-modifying therapies that put us on the critical pathway to preventing and ultimately curing type 1 diabetes,” JDRF said in a statement.
Miriam E. Tucker is a freelance journalist based in the Washington, DC, area. She is a regular contributor to Medscape, with other work appearing in The Washington Post, NPR’s Shots blog, and Diabetes Forecast magazine. She is on Twitter: @MiriamETucker.