Following consultation with the FDA, Diamyd Medical has decided to suspend dosing in a U.S. Phase III study, DiaPrevent, with the antigen-based therapy Diamyd and to initiate closure of the study.
Study closure activities will commence promptly. The decision follows a blinded review of the efficacy data collected to date in the study as well as the previously reported negative outcome of a European Phase III study of the same design, according to the Stockholm-based company.
"It is sad to report that we are terminating the current Phase III program with Diamyd," says Peter Zerhouni, acting president and CEO of Diamyd. "Our review of the available data suggests the DiaPrevent study is not likely to reach a positive outcome regarding efficacy and therefore it cannot be justified to complete the study as originally planned. However, the safety profile remains good. We want to express our sincere gratitude to all the study participants, as well as their families and the many doctors and nurses in the study."
The Phase III study conducted in the U.S., DiaPrevent, has enrolled more than 320 patients between 10 and 20 years of age who were diagnosed with type 1 diabetes within three months of entering the study. The study includes three treatment arms in which one-third of the patients were scheduled to receive four subcutaneous injections of Diamyd; one-third to receive two injections of Diamyd; and one-third to receive placebo (non-active substance). The injections were to be given over a period of nine months. The last patient randomized into the study received the first injection of Diamyd or placebo in December 2010. The study included a main study period of 15 months, but this will now be shortened.
On May 9, the company reported that its parallel European Phase III study with Diamyd did not meet the primary efficacy endpoint of preserving beta cell function at 15 months, as measured by meal stimulated C-peptide, although a small positive effect was seen. Furthermore, Diamyd was well tolerated as demonstrated by a similar number of adverse events in the Diamyd treated groups as well as in the placebo treated group. The follow-up period of the European Phase III study was closed on June 1. Detailed results from the European study will be presented at the American Diabetes Association's 71 scientific sessions (ADA) in San Diego on June 28.
The research consortium Type 1 Diabetes TrialNet is conducting a Phase II trial with Diamyd in the U.S. and Canada with a similar study design. Study results will be presented at the ADA in San Diego, on June 27.