- Broad labeling inclusive of all disease subtypes for individuals 1 month of age and older -
- PTC will host a conference call on Monday, July 28th at 5:00 pm ET -
WARREN, N.J., July 28, 2025 /PRNewswire/ -- PTC Therapeutics, Inc. (NASDAQ: PTCT) announced today that the U.S. Food and Drug Administration (FDA) has approved SEPHIENCE™ (sepiapterin) for the treatment of children and adults living with phenylketonuria (PKU). The approval includes broad labeling for the treatment of hyperphenylalaninemia (HPA) in adult and pediatric patients 1 month of age and older with sepiapterin-responsive PKU.
"We are excited to have reached this important milestone for those affected by PKU," said Matthew B. Klein, M.D., Chief Executive Officer of PTC Therapeutics. "The broad labeling reflects the potential of Sephience to meet the significant unmet need of PKU patients. The Sephience clinical data along with our expertise in launching rare disease therapies position Sephience to become the future standard of care. Our experienced customer facing teams are ready to bring this therapy to children and adults with PKU in the United States as quickly as possible."
The FDA approval is based on the evidence of significant efficacy and safety from the Phase 3 APHENITY trial as well as durability of treatment effect in the APHENITY long-term extension study.
"The approval marks an exciting milestone for the PKU community," said Catherine Warren, Executive Director of the National PKU Alliance. "This progress brings renewed hope, and we are eager to see the positive impact this new treatment option will have on advancing care and potentially improving quality of life for individuals of all ages and PKU subtypes that respond to this therapy."
SEPHIENCE was recently granted marketing authorization by the European Commission. Review of approval applications is ongoing in several other countries including Japan and Brazil.
Conference Call and Webcast
PTC will hold a conference call Monday, July 28, 2025 at 5:00 pm ET to discuss this news. To access the call by phone, please click here to register and you will be provided with dial-in details. To avoid delays, we recommend participants dial in to the conference call 15 minutes prior to the start of the call. The webcast conference call can be accessed on the Investor section of the PTC website at https://ir.ptcbio.com/events-presentations. A replay of the call will be available approximately two hours after completion of the call and will be archived on the company's website for 30 days following the call.
About SEPHIENCE™ (sepiapterin)
SEPHIENCE is indicated for the treatment of hyperphenylalaninemia (HPA) in adult and pediatric patients with phenylketonuria (PKU). Sephience is a natural precursor of the enzymatic co-factor BH4, a critical co-factor for phenylalanine hydroxylase (PAH). Through its mechanism of action, Sephience is able to effectively reduce blood phenylalanine (Phe) levels and has the potential to treat a broad range of PKU patients. Sephience is approved in the European Economic Area and the United States.
About Phenylketonuria
Phenylketonuria (PKU) is a rare, inherited metabolic disease, which affects the brain. It is caused by a defect in the gene that helps create the enzyme needed to break down phenylalanine (Phe). If left untreated or poorly managed, Phe—an essential amino acid found in all proteins and most foods—can build up to harmful levels in the body. This causes severe and irreversible disabilities, such as permanent intellectual disability, seizures, delayed development, memory loss, and behavioral and emotional problems. Newborns with PKU initially do not have any symptoms, but symptoms are usually progressive, and damage caused by toxic levels of Phe in the first few years of life is irreversible. Diagnosis of PKU usually takes place during newborn screening programs. There are an estimated 58,000 people living with PKU globally.
About PTC Therapeutics, Inc.
PTC is a global biopharmaceutical company dedicated to the discovery, development and commercialization of clinically differentiated medicines for children and adults living with rare disorders. PTC is advancing a robust and diversified pipeline of transformative medicines as part of its mission to provide access to best-in-class treatments for patients with unmet medical needs. The company's strategy is to leverage its scientific expertise and global commercial infrastructure to optimize value for patients and other stakeholders.