An estimated 5,000 to 10,000 people are affected in the developed world. In the most severe form of Pompe's disease, in which little or no functioning acid maltase is produced, infants are affected and usually don't live more than a year. Without acid maltase, glycogen, a starchy material, builds up in muscles, including the heart and critical respiratory muscles. This buildup interferes with muscle function and leads to severe weakness, along with cardiac and respiratory failure. Three infants were treated at Duke and received the enzyme by intravenous infusion for over a year.
Preliminary results indicate that the enzyme can improve cardiac and skeletal muscle function.
They continue to show improved cardiac function, thus avoiding the usual progressive cardiac muscle deterioration resulting in heart failure and death. Improvements of skeletal muscle function have also been noted, although the significance and extent have been more variable than results seen in the heart. Muscle biopsies have confirmed that significant reductions in toxic glycogen accumulation occurred in at least one patient after the enzyme replacement therapy. The therapy has been well tolerated. MDA is a voluntary health agency working to defeat neuromuscular disease through programs of worldwide research, comprehensive services, and far-reaching professional and public health education.