A total of 26 subjects completed either 12 or 24 weeks of treatment during Phase II studies – 23 of the 26 subjects continue to receive treatment in an ongoing extension study designed to evaluate the long-term safety and efficacy of Amigal; 10 of the 23 subjects have been on treatment for at least two years and four subjects have been on treatment for more than three years.
Treatment with Amigal was generally well-tolerated, with no drug-related serious adverse events, the company said. Subjects identified as responders to Amigal at the completion of the Phase II studies continued to maintain elevated levels of the target enzyme (a-Gal A), as measured in white blood cells, and reduced levels of the target substrate (kidney GL-3), as measured in urine.
A reduction of GL-3 levels was also observed in interstitial capillary cells from kidney biopsies. Previously reported Phase II results indicated that little to no GL-3 was detected in these cells in most subjects prior to treatment with Amigal. The new data were obtained from the retesting of biopsies using an improved methodology, the company added.
Amicus is developing Amigal as part of a strategic collaboration with Shire Human Genetic Therapies, a business unit of Shire, to develop and commercialize Amicus’s three lead pharmacological chaperone compounds for lysosomal storage disorders. Under the agreement, Shire received commercial rights outside of the US. Amicus retains all US rights.
John Crowley, president and CEO of Amicus Therapeutics, said: “We are very pleased with this additional set of Phase II data and are very confident we have a solid basis for a successful Phase III program. We continue to work in collaboration with the FDA and remain on track to finalize our protocol and initiate the Phase III program in the second quarter of 2009.”