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Sephience (SEPIAPTERIN)
Sephience works by replenishing tetrahydrobiopterin (BH4), a critical cofactor for amino acid metabolism.
At a glance
| Generic name | SEPIAPTERIN |
|---|---|
| Sponsor | Ptc Therap |
| Modality | Small molecule |
| Therapeutic area | Metabolic |
| Phase | FDA-approved |
| First approval | 2025 |
Mechanism of action
SEPHIENCE is a precursor of the enzymatic co-factor tetrahydrobiopterin (BH 4 ) which activates PAH.
Approved indications
- hyperphenylalaninemia (HPA)
- sepiapterin-responsive phenylketonuria (PKU)
Common side effects
- Diarrhea
- Headache
- Abdominal pain
- Hypophenylalaninemia
- Feces discoloration
- Oropharyngeal pain
- Increased bleeding
- Heavy menstrual bleeding
- Non-traumatic superficial hematomas
- Prolonged bleeding
Drug interactions
- trimethoprim
- methotrexate
- trimetrexate
- pemetrexed
- pralatrexate
- raltitrexed
- piritrexim
- sulfasalazine
- sulfamethoxazole
- levodopa
- PDE-5 inhibitors
- sildenafil
Key clinical trials
- A Study of PTC923 in Participants With Phenylketonuria (PHASE3)
- A Study of Sepiapterin in Participants With Phenylketonuria (PKU) (PHASE3)
- A Long-Term Safety Study of PTC923 in Participants With Phenylketonuria (PHASE3)
- A Study of PTC923 (CNSA-001) in Primary Tetrahydrobiopterin (BH4) Deficient Participants With Hyperphenylalaninemia (PHASE1,PHASE2)
- A Study of CNSA-001 in Women With Diabetic Gastroparesis (PHASE2)
Patents
| Patent | Expiry | Type |
|---|---|---|
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| FDA label | Mechanism, indications, dosing, boxed warnings, drug interactions |
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
| FDA Orange Book | Patents + exclusivity |