Zenith 1
Research type
Research Study
Full title
A Phase 3, Randomized, Double-Blind, Placebo-Controlled, 3-Arm Study to Investigate the Safety and Efficacy of Efimosfermin Alfa in Participants With Biopsy-Confirmed F2- or F3-Stage Metabolic Dysfunction-Associated Steatohepatitis (MASH) (ZENITH-1)
IRAS ID
1013369
Contact name
Derek Moriarty
Contact email
Sponsor organisation
GSK Research & Development Limited
ISRCTN Number
ISRCTN73563399
Research summary
This is a randomized, double-blind, placebo-controlled, parallel-group, multicenter, 48-month study of the safety and efficacy of efimosfermin administered every 4 weeks (Q4W) by subcutaneous (SC) injection in adult MASH participants with fibrosis that is consistent with stage F2 or F3. The total time of participation in the study, inclusive of Screening and safety follow-up, is approximately 52 months.
The purpose of this study is to assess the safety and efficacy of monthly efimosfermin injection in the resolution of steatohepatitis and improvement of liver-related clinical outcome compared to placebo in individuals with MASH and biopsy-confirmed F2- or F3-stage fibrosis following a maximum treatment duration of 48 months. Approximately 1200 participants will be randomized.
Participants will be enrolled and randomized 1:1:1 to receive 225 mg efimosfermin, 300 mg efimosfermin, or placebo Q4W by SC injection for a period of 48 months, followed by a final follow-up safety assessment at Week 212 of the study. Total time of participation in the study, inclusive of a screening period of up to 3 months and the final safety assessment, is approximately 52 months. Since injection volumes for the 225-mg and 300-mg efimosfermin arms are 1.5 mL and 2.0 mL, respectively, additional measures will be implemented to preserve the study blind.
Criteria are established in this protocol for dose interruption, modification, discontinuation, and resumption based on Investigator discretion and following consultation with the Study Medical Monitor (the Sponsor or designee) in specific circumstances.REC name
London - London Bridge Research Ethics Committee
REC reference
26/LO/0252
Date of REC Opinion
10 May 2026
REC opinion
Further Information Favourable Opinion