Genzyme, a Sanofi company, has started an open label, single-arm Phase IIa clinical trial of GZ/SAR402671, a new oral substrate reduction therapy to treat patients with Fabry disease, a rare lysosomal storage disorder.

Around nine treatment-naïve male adult patients with Fabry disease will be enrolled in this international, multi-centre trial, which is designed to evaluate the safety, tolerability and pharmacokinetics of GZ/SAR402671.

Fabry disease is characterised by excessive accumulation of the lipid GL-3 in various organs and tissues. The disease results in abnormal tissue deposits of a particular fatty substance (globotriaosylceramide, also referred to as GL-3 or Gb3) throughout the body.

The company said that GZ/SAR402671 is a glucosylceramide synthase inhibitor that blocks the formation of glucosylceramide (GL-1), a key intermediate in the synthesis of GL-3.

In this trial, patients will receive GZ/SAR402671 orally, once daily and its primary endpoint will assess the ability of GZ/SAR402671 to reduce accumulated GL-3 from the skin capillary endothelium.

Genzyme Rare Diseases acting head Richard Peters said: "We are excited to learn more about the potential of GZ/SAR402671, which has a different mechanism of action than the current standard of treatment for Fabry disease, enzyme replacement therapy, and a potential ability to cross the blood brain barrier.

"The ongoing efforts on this program underscore our long standing commitment to develop innovative therapies intended to address the unmet needs of the Fabry patient community."

Following completion of the 26 week trial, patients will have the option to enrol into an extension study.