The U.S. Food and Drug Administration (FDA) granted orphan drug status to Polaryx Therapeutics’ PLX-200 in response to a lack of treatments available for late infantile neuronal ceroid lipofuscinosis (LINCL), a type of Batten disease.
PLX-200 is a repurposed drug (one that was developed for one indication but is effective in other conditions) that binds to the retinoid X receptor-alpha to regulate the activity of TTP1 protein in brain cells.
PLX-200 is also designed to enhance production of transcription factor EB (TFEB) in brain cells. TFEB binds to the promoter of genes involved in lysosome biogenesis, activating their production. It can also regulate lysosomes due to its effects on the expression of lysosomal genes. Lysosomes are the part of the cell responsible for degradation of proteins and other waste materials.
“Granting PLX-200 the Orphan Drug Designation is one of the company’s significant development milestones,” Hahn-Jun Lee, PhD, president and CEO of Polaryx, said in a press release. “We will accelerate this program into clinics as early as possible to help LINCL patients. We will confirm the efficacy of PLX-200 in humans and further confirm that it can be applied to other types of NCL disorders.”
Kalipada Pahan, PhD, a professor of neurological sciences, biochemistry and pharmacology at Rush University Medical Center in Chicago, said the FDA’s decision recognizes the “significant value of our technology that led to the extension of survival of a LINCL animal disease model and delayed the decline in motor function. As this is a patient-friendly new treatment option that is a safely-used oral small molecule, it will help a lot to patients in many aspects.”
LINCL also qualifies as an FDA rare pediatric disease. Its orphan disease status means it affects fewer than 200,000 people in the United States.
LINCL is caused by mutations in the Cln2 gene and leads to abnormal functioning of tripeptidyl peptidase 1 (TPP1), which then leads to the accumulation of certain proteins and other substances in neurons and in other cells, leading to nerve damage and cell death.
LINCL is a neurodegenerative disorder with no current patient-friendly treatment options available.