FDA Grants DepYmed Rare Pediatric Disease Designation for Rett Syndrome Candidate

The U.S. Food and Drug Administration granted DepYmed Rare Pediatric Disease and Orphan Drug designations for its lead clinical candidate, a small molecule PTP1B inhibitor for the treatment of patients with Rett Syndrome.

Photo: Andreas Grill, DepYmed’s President and CEO of DepYmed

Rett syndrome is a progressive neurodevelopmental disorder that almost exclusively affects females. Infants with Rett syndrome generally develop normally for 6 to 18 months after birth. At this point, they lose previously acquired skills (developmental regression) such as purposeful hand movements and the ability to communicate. Affected children often develop autistic-like behaviors, breathing irregularities, feeding and swallowing difficulties, growth retardation, and seizures. Most Rett syndrome cases are caused by mutations of the MECP2 gene on the X chromosome and can present with a wide range of disability ranging from mild to severe. The expression of PTP1B, DepYmed’s target in Rett syndrome, is regulated by MECP2; in turn, PTP1B controls important cell functions that are disrupted in the disease.

Protein tyrosine phosphatases are major players in the control of cell signaling pathways that are disrupted in many diseases; however, to date, development of drug modulators of these enzymes has not been successful. DepYmed said it is the first company to develop a new class of orally bioavailable drug candidates that act by inhibiting PTP1B, one of the most important PTP drug targets. One of its lead compounds has shown promising efficacy in preclinical models of Rett syndrome, and the company hopes to initiate a phase 1 clinical trial later this year.

The FDA defines a rare pediatric disease as a serious or life-threatening disease in which the disease manifestations primarily affect individuals aged from birth to 18 years. Pediatric diseases recognized as rare affect fewer than 200,000 people in the United States.

Under the FDA’s Rare Pediatric Disease designation and Voucher programs, if DepYmed receives marketing approval for its PTP1B inhibitor for Rett syndrome, the company may be eligible to receive a Priority Review Voucher (PRV) from the FDA. The voucher can be used to reduce the time of an FDA new drug approval review to six months from ten months. The vouchers are potentially lucrative because they are transferable. Most recently, BioMarin Pharmaceutical sold its voucher for $110 million.

“FDA’s decision to grant these designations for our lead clinical candidate for the treatment of Rett Syndrome is a significant achievement for DepYmed,” said Andreas Grill, president and CEO of DepYmed. “Further, it perfectly aligns with our mission to provide treatments for patients where few if any options exist and highlights the urgent need to develop a treatment for patients with Rett Syndrome, a devastating rare genetic neurological disorder that occurs primarily in girls.”

Author: Rare Daily Staff