Polaryx Therapeutics Announces FDA Grants Orphan Drug Designation For PLX-200 In GM2 Gangliosidoses

Paramus, NJ /PRNewswire/ - Polaryx Therapeutics, Inc. ("Polaryx"), a biotech company developing small molecule therapeutics for lysosomal storage disorders, announced today that the U.S. Food and Drug Administration ("FDA") has granted Orphan Drug Designation for PLX-200 to treat GM2 gangliosidoses.

GM2 Gangliosidoses, also known as Tay-Sachs and Sandhoff diseases, are ultra-rare and fatal pediatric neurodegenerative disorders caused by defects in Hexosaminidase A (HEXA) and Hexosaminidase B (HEXB), key enzymes in the lysosome, respectively. These genetic defects lead to abnormal accumulation of gangliosides, resulting in severe progressive neurodegeneration, seizures, loss of mobility, hearing, and vision, and early death. There is no cure for these diseases and the only treatment is supportive care.

Under the U.S. Orphan Drug Act, the FDA's Office of Orphan Products Development provides sponsors with special status and incentives to facilitate drug development for rare disease affecting fewer than 200,000 people in the U.S. Orphan Drug Designation provides seven years of market exclusivity if the drug candidate receives regulatory approval together with tax credits for qualified clinical trial cost, exemptions from certain FDA application fees, and assistance in clinical trial design.

"We are very pleased to be granted Orphan Drug Designation for PLX-200 from the FDA for the treatment of GM2 gangliosidoses. This designation is one of the important development milestones for the company, because it allows an expanded use of PLX-200 to one of the key lysosomal storage disorders which have clear unmet medical needs. Furthermore, this designation validates the rationale for clinical use of PLX-200 in GM2 gangliosidoses patients. Our team is poised to initiate a clinical study to confirm its efficacy in GM2 gangliosidoses," says Dr. Hahn-Jun Lee, M.Sc., Ph.D., President and CEO of Polaryx Therapeutics, Inc.

Alex Yang, J.D., LLM, President and CEO of Mstone Partners Hong Kong and Chair of the Board at Polaryx Therapeutics stated that "We are committed to provide innovative and patient-friendly drugs to treat a number of rare lysosomal storage disorders, including but not limited to Batten, Niemann-Pick and now Tay-Sachs diseases. With the completion of this milestone, we have comprehensively seized critical regulatory designations to efficiently move forward with the commercialization in lysosomal storage disorders."

Polaryx Therapeutics, Inc.
Polaryx Therapeutics, Inc. is developing drug candidates for lysosomal storage disorders, for which there are currently no safe and patient-friendly treatment options available. Lysosomal storage disorders are a group of rare inherited genetic disorders caused by the dysfunction of lysosomal enzymes and/or molecules important in the function of these enzymes. Young children are victims of these devastating diseases and die at an early age due to lack of treatment options.

PLX-200
PLX-200 is a repurposed drug that binds to the retinoid X receptor-α (RXRα), which binds to PPARα. PLX-200 also activates PPARα, which enhances production of transcription factor EB (TFEB). TFEB then binds to the promoter of genes involved in lysosome biogenesis and activates their production. PLX-200 also has additional activities, such as reducing inflammation and preventing cell death (apoptosis).

GM2 gangliosidoses
The GM2 gangliosidoses is caused by mutations in the HEXA and HEXB genes encoding subunits of ganglioside β-hexosaminidase (Hex), the lysosomal enzyme that normally degrades GM2. As a result, GM2 ganglioside accumulates in the lysosomes of nerve cells resulting in distended neurons engorged with swollen lysosomes (membranous cytoplasmic bodies; MCB) throughout the nervous system. There are 2 major forms of Hex: HEXA, a heterodimer composed of one α and one β subunit, and HEXB, composed of 2 β subunits. Tay-Sachs disease is caused by mutations in the HEXA gene encoding the α subunit of HEXA. The much rarer Sandhoff disease, a more severe form of Tay-Sachs disease, is caused by mutations in the HEXB gene encoding the β subunit, leading to deficiency of both HEXA and HEXB activities.