A Phase 3 Study of Sepiapterin vs Sapropterin in Participants with Phenylketonuria ≥ 2 years of age

• Research type

  Research Study

• Full title

  A Phase 3, Randomized, Crossover, Open-Label, Active-Controlled Study of Sepiapterin versus Sapropterin in Participants With Phenylketonuria ≥2 years of Age

• IRAS ID

  1008747

• Contact name

  Kimberly Ingalls

• Contact email

  Medinfo@ptcbio.com

• Sponsor organisation

  PTC Therapeutics, Inc.

• ISRCTN Number

  ISRCTN79102999

• Research summary

  The main purpose of this study is to see how the study drug, sepiapterin, affects blood Phe levels in the body compared with the maximum recommended daily dose of an already known and commercially available treatment called sapropterin in participants with PKU (≥2 years of age).
  The study duration for each participant will be up to 173 days from Screening to the final study visit. Following a screening period of up to 45 days, all enrolled participants will receive sepiapterin for 2 weeks followed by a minimum 14-day sepiapterin washout period in Part 1. Participants with ≥20% reduction in blood Phe levels to sepiapterin will continue into Part 2 where they will receive sequential treatment with 4 weeks of sepiapterin and 4 weeks of sapropterin (order determined by randomisation) within each treatment period, separated by a 14-day washout. After completion of the second 14-day washout period, participants will be offered the option to enroll directly into an open-label long-term Study PTC923-MD-004-PKU. There will be approximately 100 participants enrolled in Part 1 and approximately 42 participants randomised into Part 2 of this study.

• REC name

  London - Hampstead Research Ethics Committee

• REC reference

  23/LO/0939

• Date of REC Opinion

  13 Dec 2023

• REC opinion

  Further Information Favourable Opinion