A Phase III study evaluating Tolerx and GlaxoSmithKline’s (GSK) otelixizumab in the treatment of type 1 diabetes has failed to meet its primary endpoint, prompting the firms to suspend a second, confirmatory Phase III study. The Defend-1 study showed that treatment using the humanized anti-CD3 monoclonal antibody did not change C-peptide levels at one year when used to treat patients with new-onset autoimmune type 1 diabetes. New patient recruitment and dosing in the confirmatory Defend-2 study has been suspended pending review of the Defend-1 data.
“Clearly these are disappointing data, but we are committed to working with Tolerx to better understand the results of this study and determine the way forward,” said Jackie Parkin, medicines development leader at GSK.
Tolerx licensed otelixizumab from BTG and subsequently teamed up with GSK for worldwide development of the autoimmune diseases candidate back in 2007. According to BTG, GSK will continue to look into additional dosing regimens for otelixizumab to help in the decision-making process for other clinical development programs.
Otelixizumab is currently in various stages of clinical development as a potential treatment for a range of autoimmune diseases, including Graves eye disease, rheumatoid arthritis, and myasthenia gravis. “The result of the Defend-1 study is obviously disappointing, though we note that GSK is continuing development of otelixizumab in autoimmune diseases,” notes Louise Makin, BTG’s CEO.
Under the terms of the agreement between GSK and Tolerx, the latter has been responsible for conducting the Phase III clinical program and regulatory submission for the type 1 diabetes indication in the U.S. Tolerx also retains the option to co-promote otelixizumab in type 1 diabetes in the U.S. with GSK. The U.K. drugs giant has exclusive rights to develop and commercialize otelixizumab in all indications worldwide, including pediatric type 1 diabetes.