Niemann-Pick disease type C (NPC) is a rare progressive neurodegenerative disease. It belongs to the family of lysosomal storage diseases. Niemann-Pick disease type C can be difficult to recognize, which leads to diagnostic delays. There are no approved treatments in the United States for Niemann-Pick disease type C.

Gaucher disease is a rare, inherited lysosomal storage disorder causing certain sugar-containing fats to abnormally accumulate in the lysosomes of cells, especially within cells of the blood system and nerve cells, thereby affecting organs such as the brain, bone marrow, spleen, and liver. The typical systemic symptoms of Gaucher disease, which can appear at any age, include an abnormally enlarged liver and/or spleen and low levels of circulating red blood cells and platelets. Currently no treatments are available that can cross the blood brain barrier to help reduce neurological symptoms.