Next-Generation Enzyme Replacement Therapies: Alpha-Glucosidase, for the treatment of Pompe Disease
We are developing a next-generation alpha-glucosidase replacement therapy for the treatment of Pompe disease. Pompe disease, also known as Acid Maltase Deficiency or Glycogen Storage Disease type II, is an inherited muscular myopathy disorder caused by the build-up of a complex sugar called glycogen in the body’s cells. It affects around 1 in 40,000 people in general, varying within different ethnic groups. Pompe disease is a rare multisystem genetic disorder that is characterized by absence or deficiency of the lysosomal enzyme alpha-glucosidase, or GAA.
This enzyme is required to break down, or metabolize, the complex carbohydrate glycogen and convert it into the simple sugar glucose. Glycogen is a thick, sticky substance and failure to achieve proper breakdown results in massive accumulation of lysosomal glycogen in cells, particularly in cardiac, smooth, and skeletal muscle cells.
Pompe disease is a single-disease continuum with variable rates of disease progression and different ages of onset. The infantile form is characterized by severe muscle weakness and abnormally diminished muscle tone, or hypotonia, without muscle wasting, and usually manifests within the first few months of life. Additional abnormalities may include enlargement of the heart, or cardiomegaly, the liver, or hepatomegaly, and/or the tongue, or macroglossia. Without treatment, progressive cardiac failure usually causes life-threatening complications by the age of 12 to 18 months. Pompe disease can also present in childhood, adolescence or adulthood, collectively known as late-onset Pompe disease. The extent of organ involvement may vary among affected individuals, but skeletal muscle weakness is usually present with minimal cardiac involvement. Initial symptoms of late-onset Pompe disease may be subtle and may go unrecognized for years.
We are currently studying our alpha-glucosidase therapy in IND-enabling studies.