The U.S. Food and Drug Administration recently gave a green light on Mepsevii to treat pediatric and adult patients with an inherited metabolic health condition called mucopolysaccharidosis type VII (MPS VII), also identified as Sly syndrome. MPS VII is an extremely rare, progressive condition that affects most tissues and organs.
“This approval underscores the agency’s commitment to making treatments available to patients with rare diseases,” stated Julie Beitz, M.D., director of the Office of Drug Evaluation III in the FDA’s Center for Drug Evaluation and Research (CDER). “Prior to today’s approval, patients with this rare, inherited condition had no approved treatment options.”
MPS VII is an inherited, rare genetic health condition that has impacted less than 150 patients worldwide. The features of MPS VII vary widely from patient to patient, but most patients have various skeletal abnormal health conditions that have become more pronounced with age, including short stature. Affected individuals can also develop heart valve abnormalities, enlarged liver, and spleen, and narrowed airways which can lead to lung infections and trouble breathing. The life expectancy of individuals with MPS VII depends on the severity of symptoms. Some affected individuals do not survive infancy, while others may live into adolescence or adulthood. Heart disease and airway obstruction are major causes of death in people with MPS VII. Affected individuals may have developmental delay and progressive intellectual disability.
MPS VII is a lysosomal storage disorder caused by the deficiency of an enzyme that is identified as beta-glucuronidase, which is known to causes an abnormal buildup of toxic materials in the body’s cells. Mepsevii is an enzyme replacement therapy that works by replacing the missing enzyme. The safety and efficacy of Mepsevii were established in a clinical trial and expanded access protocols enrolling a total of 23 patients ranging from 5 months to 25 years of age.