The U.S. Food and Drug Administration (FDA) has granted orphan drug designation to two gene therapies that M6P Therapeutics is developing — one intended for Gaucher disease, the other aiming to treat the inherited metabolic disorder mucolipidosis.
The regulatory agency also awarded six rare pediatric disease designations to various investigational therapies that M6P Therapeutics is developing to treat lysosomal storage disorders, which include Gaucher and mucolipidosis.
“We are grateful to the FDA for these multiple orphan and rare pediatric disease designations that highlight the need for new and improved therapies to address unmet needs,” Pawel Krysiak, president and CEO of M6P Therapeutics, said in a press release.
Lysosomal storage disorders are conditions in which the function of the lysosome — necessary for cell maintenance — is impaired due to missing or defective enzymes. These conditions usually result from mutations in the genes that code for those enzymes. Often described as the cellular “garbage disposal” or “recycling machinery,” lysosomes are responsible for breaking down certain cellular products.
In these disorders, lysosomes do not work properly, causing cellular components to build up to toxic levels. For example, in Gaucher disease, a lack of the lysosomal enzyme beta-glucocerebrosidase leads to a buildup of the cellular component glucocerebroside.
Mannose 6-phosphate, or M6P, is a small sugar molecule that can be attached to lysosomal enzymes. The company’s approach of increasing the mannose 6-phosphate content of gene therapies or enzyme replacement therapies is meant to improve treatment delivery into lysosomes by binding to specific receptors.
Enzyme replacement therapies, as the name suggests, seek to provide a functional version of the defective enzyme to people with the disease. In turn, gene therapies aim to deliver a non-mutated version of a gene to the body’s cells, allowing patients to make their own functional lysosomal enzymes.
“Our innovative platform enables efficient trafficking of either a recombinant enzyme or gene therapy product to the affected cells and tissues and has the potential to generate best-in-class treatments for [lysosomal storage disorders],” Krysiak said.
The FDA grants orphan drug designation to investigational therapies with the potential to substantially improve care for people with rare diseases, defined as those that affect fewer than 200,000 people in the U.S. This status confers several incentives on the therapy’s developer, such as fee waivers and the possibility of seven years of market exclusivity if the treatment is ultimately approved.
Rare pediatric disease designation is given by the FDA to therapies that aim to treat rare conditions that primarily affect individuals ages 18 or younger. Under this program, the FDA gives the therapy’s sponsor — in this case, M6P Therapeutics — a voucher that can be redeemed for priority review of future marketing applications. The voucher can be used by the developer or sold or traded.