PTC Therapeutics
PTC Therapeutics works on 17 rare diseases tracked on Trial Friend, including Aromatic L-Amino Acid Decarboxylase Deficiency, Amyotrophic Lateral Sclerosis, Becker Muscular Dystrophy and 14 more, with 4 recruiting clinical trials and 3 FDA-approved rare disease drugs.
PTC Therapeutics develops medicines for rare metabolic and neurological diseases.
Approved products include Sephience (sepiapterin) for phenylketonuria (FDA approved July 2025) and Kebilidi (eladocagene exuparvovec), a gene therapy for AADC deficiency (FDA approved November 2024). PTC also receives royalties from Roche on Evrysdi (risdiplam) for spinal muscular atrophy.
The company's most-watched program is votoplam (PTC518), an oral pill for Huntington's disease that lowers the toxic huntingtin protein responsible for the condition. Novartis took over development, manufacturing, and commercialization in 2024.
On April 28, 2026, PTC reported positive 24-month results from the PIVOT-HD long-term extension. Patients on the higher 10 mg dose showed 52% slowing of disease progression on the standard Huntington's clinical scale (cUHDRS) compared with natural history, with 28% slowing at 5 mg. Markers of nerve damage (NfL) stayed below baseline at both doses, in contrast to the rise typically seen in untreated HD. Novartis has now started the global Phase 3 INVEST-HD trial in roughly 770 patients with early-stage disease.
Vatiquinone for Friedreich ataxia remains in development after receiving an FDA Complete Response Letter that requested more efficacy data.
On September 21, 2026, PTC completed its acquisition of ST-920 (isaralgagene civaparvovec), a one-time AAV gene therapy for Fabry disease, from Sangamo's bankruptcy auction. The rolling BLA for accelerated approval is expected to be completed in Q4 2026.
PTC Therapeutics Drug Pipeline
PTC Therapeutics has 4 active clinical trials across 3 development stages, with 4 currently recruiting participants. Clinical trials advance through phases: Phase 1 tests safety in a small group, Phase 2 evaluates effectiveness and side effects, Phase 3 confirms benefit in a larger population, and Phase 4 monitors long-term safety after FDA approval.
Note: This pipeline includes all of PTC Therapeutics's active interventional trials, not only those targeting rare diseases. We show the full pipeline because a company's broader research activity, therapeutic expertise, and development infrastructure directly shape its ability to advance rare disease programs. A strong overall pipeline often signals deeper clinical operations, faster enrollment capabilities, and greater commitment to bringing new treatments to patients.
PTC Therapeutics Clinical Trials (4)
Active and recruiting clinical trials sponsored by PTC Therapeutics, sourced live from ClinicalTrials.gov. Each trial card shows the study phase, current recruitment status, conditions under investigation, study locations, eligibility criteria, and a direct link to the full ClinicalTrials.gov record. You can also download a one-page PDF summary to share with your doctor.
Note: Recruitment statuses on ClinicalTrials.gov may not immediately reflect recent FDA decisions, sponsor announcements, or enrollment changes. Always confirm a trial's current status directly with the study coordinator.
PTC Therapeutics FDA-Approved Drugs (3)
Medications developed or marketed by PTC Therapeutics that have received U.S. Food and Drug Administration approval. Drug data is sourced from the openFDA database and includes brand names, generic names, approval dates, and matched rare disease indications. Where a drug treats a condition covered by Trial Friend, the disease name links directly to that disease page.
| Drug Name | Brand Name | Rare Diseases | Approval Date |
|---|---|---|---|
| DEFLAZACORT Corticosteroid [EPC] | EMFLAZA oral | Feb 9, 2017 | |
| SEPIAPTERIN | Sephience oral | Jul 28, 2025 | |
| ELADOCAGENE EXUPARVOVEC-TNEQ | KEBILIDI intracerebral | — | — |
PTC Therapeutics Trial Locations
PTC Therapeutics clinical trials are running at 40 sites in 14 countries. Click any country to drill down by state, city, and individual research facility. Proximity to a trial site is one of the most important factors in deciding whether to participate.
Rare Disease Focus Areas (17)
Diseases targeted by PTC Therapeutics's clinical trial and drug development programs
AADC deficiency is a rare inherited neurological disorder that affects the brain's ability to produce dopamine and serotonin, leading to severe developmental delays, movement problems, and involuntary...
Amyotrophic lateral sclerosis is a progressive neurodegenerative disease destroying motor neurons in the brain and spinal cord. This causes progressive weakness and paralysis of voluntary muscles whil...
Becker Muscular Dystrophy (BMD) is an X-linked inherited muscular dystrophy caused by mutations in the dystrophin gene that produce a partially functional dystrophin protein. BMD is milder than Duchen...
Cystic fibrosis is an autosomal recessive genetic disorder affecting the CFTR protein, which normally regulates chloride transport. Defective CFTR causes thick, sticky secretions in the lungs and dige...
Diffuse intrinsic pontine glioma (DIPG) is an aggressive childhood brain tumor that grows in the pons, the part of the brainstem controlling breathing, swallowing, and movement. Because it weaves thro...
Dravet Syndrome is a severe form of epilepsy that typically begins in infancy with prolonged seizures triggered by fever. Most cases are caused by mutations in the SCN1A gene encoding a sodium channel...
Patient Resources
Organizations and resources related to PTC Therapeutics's rare disease focus areas
Frequently Asked Questions About PTC Therapeutics
Common questions about PTC Therapeutics's rare disease programs, clinical trials, and treatments.