Metabolic Dysfunction-Associated Steatohepatitis (MASH)Phase 2NCT07631637
Study to Evaluate ALN-CIDEB in Adults With Fibrotic Metabolic Dysfunction-Associated Steatohepatitis (MASH)
A Phase 2 study testing ALN-CIDEB in people with Metabolic Dysfunction-Associated Steatohepatitis (MASH), run by Regeneron Pharmaceuticals at 16 sites in 2 countries.
Trial summary
This study will test a Regeneron study drug called ALN-CIDEB to find out whether it may help treat a liver disease called MASH. In this study, researchers are looking at the effect of ALN-CIDEB on reducing liver fat, liver injury, and liver scarring. Read more about this study
- Who is it for?
- Ages 18 to 75 years
- Conditions the study is for
- Metabolic Dysfunction-Associated Steatohepatitis (MASH)
- What is being tested?
- ALN-CIDEB
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 150 participants
- Where
- 16 sitesin 2 countries
- Study dates
- 6 Jul 2026to 29 Jan 2029
- Phase
- Phase 2
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 75 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- A diagnosis of MASH documented in the participant's medical history, or a clinical suspicion of MASH based on non-invasive biomarkers and clinical risk factors, including having a history of 1 or more elements of metabolic syndrome as described in the protocol
- Screening percutaneous liver biopsy demonstrating a NAFLD Activity Score (NAS) ≥4 and fibrosis stage F2 or F3 as described in the protocol
- Has a FibroScan Aspartate aminotransferase (FAST) score >0.35 either at Screening Visit 1 or within approximately 3 months of Screening Visit 1 as described in the protocol
Who cannot join
- Known chronic liver disease other than Metabolic dysfunction-Associated Steatotic Liver Disease (MASLD), as determined by the investigator as described in the protocol
- Prior or current suspected or known drug-induced liver injury within approximately 1 year prior to Screening Visit 1
- History of liver transplantation, current placement on a liver transplant list, or MELD score >12
- Known history of alcohol or other substance abuse within the last year or at any time during screening based on investigator's discretion and/or a score on the AUDIT questionnaire ≥8
- Prior current, or planned future use of a Glucagon-Like Peptide-1 (GLP-1) receptor agonist-based therapy or any medication approved for the treatment of MASH unless used at a generally stable dose and regimen since at least 3 months prior to Screening Visit 1 or the qualifying historical liver biopsy and throughout the screening period with no change to the dose or regimen anticipated during the treatment period as described in the protocol
- NOTE: Other Protocol-defined Inclusion/Exclusion Criteria Apply
Trial locations and contacts
16 sites in 2 countries. Contact the study team or a site near you to ask about taking part.
16 sites in 2 countries
United States15 sites, 15 recruiting
- Recruiting
American Research Corporation
Austin, Texas, 78757
- Recruiting
Universal Axon Clinical Research
Doral, Florida, 33166
- Recruiting
Advanced Medical Trials
Georgetown, Texas, 78628
- Recruiting
Pioneer Research Solutions, Inc.
Houston, Texas, 77099
- Recruiting
Tandem Clinical Research
Marrero, Louisiana, 70072
- Recruiting
Tandem Clinical Research
Metairie, Louisiana, 70006
- Recruiting
Genoma Research Group, Inc.
Miami, Florida, 33173
- Recruiting
Med Research of Florida, LLC
Miami, Florida, 33186
- Recruiting
California Liver Research Institute
Pasadena, California, 91105
- Recruiting
Inland Empire Clinical Trials
Rialto, California, 92377
- Recruiting
American Research Corporation at The Texas Liver Institute
San Antonio, Texas, 78215
- Recruiting
Siena Research Network
Sugar Land, Texas, 77479
- Recruiting
Adobe Clinical Research
Tucson, Arizona, 85712
- Recruiting
The Institute for Liver Health II LLC dba Arizona Liver Health
Tucson, Arizona, 85712
- Recruiting
Del Sol Research Management, LLC
Tucson, Arizona, 85715
Puerto Rico1 site, 1 recruiting
- Recruiting
Fundacion de Investigacion (FDI) Clinical Research
San Juan, 00927
About this study
Official title: A Phase 2b, Randomized, Double-Blind, Placebo-Controlled Study of ALN-CIDEB in Adults With Fibrotic Metabolic Dysfunction-Associated Steatohepatitis (MASH)
This study will test a Regeneron study drug called ALN-CIDEB to find out whether it may help treat a liver disease called MASH.
In this study, researchers are looking at the effect of ALN-CIDEB on reducing liver fat, liver injury, and liver scarring. The study will compare ALN-CIDEB with placebo to understand how well ALN-CIDEB works to lower the amount of fat in the liver.
The study is looking at:
- What side effects ALN-CIDEB might cause
- How well ALN-CIDEB works to change liver fat, liver injury, and liver scarring
- How the body and the liver change after having ALN-CIDEB, which can help researchers understand why ALN-CIDEB works better for some people than others
- Being tested
- ALN-CIDEB, Placebo
- Keywords
- F2 or F3 MASH, Fibrotic MASH, Nonalcoholic Fatty Liver Disease (NAFLD), Metabolic dysfunction-Associated Steatotic Liver Disease (MASLD), Liver Inflammation, Liver Fibrosis, Cirrhosis
- Medical subject headings
- Non-alcoholic Fatty Liver Disease, Hepatitis, Liver Cirrhosis, Fibrosis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
ALN-CIDEBDrug
Administered per the protocol
PlaceboDrug
Administered per the protocol
| Study group | Role | What they receive |
|---|---|---|
| ALN-CIDEB Dose 1 | Experimental | Not described Receives: Drug: ALN-CIDEB |
| ALN-CIDEB Dose 2 | Experimental | Not described Receives: Drug: ALN-CIDEB |
| Placebo | Placebo comparator | Not described Receives: Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Percent change from baseline in liver fat by Magnetic Resonance Imaging-derived Proton Density Fat Fraction (MRI-PDFF)
Measured: At week 26
Secondary outcomes (17)
Resolution of MASH with no worsening of Nonalcoholic Steatohepatitis-Clinical Research Network (NASH-CRN) fibrosis on liver biopsy
Measured: At week 52
Percent change from baseline in liver fat by MRI-PDFF
Measured: At week 52
Achievement of a ≥30% reduction in liver fat by MRI-PDFF
Measured: At week 52
Achievement of ≤5% liver fat by MRI-PDFF
Measured: At week 52
Percent change from baseline in liver fat by MRI-PDFF for each dose level of ALN-CIDEB
Measured: Up to week 52
Improvement of NASH-CRN Fibrosis Stage (F) by ≥1 with no worsening of MASH
Measured: At week 52
Occurrence of Treatment-Emergent Adverse Events (TEAEs)
Measured: Up to week 64
Severity of TEAEs
Measured: Up to week 64
Change from baseline in FibroScan Controlled Attenuation Parameter (CAP)
Measured: Through week 52
Change from baseline in FibroScan Liver Stiffness Measurement (LSM) by Vibration Controlled Transient Elastography (VCTE)
Measured: Through week 52
Change from baseline in Aspartate Aminotransferase (AST)
Measured: Up to week 64
Change from baseline in Alanine Aminotransferase (ALT)
Measured: Up to week 64
Change from baseline in Enhanced Liver Fibrosis (ELF)
Measured: Through week 52
Change from baseline in PRO-C3
Measured: Through week 52
Change from baseline in ADAPT
Measured: Through week 52
Change from baseline in NIS2+
Measured: Through week 52
Percent change from baseline in liver fat by MRI-PDFF in genetic subpopulations
Measured: At week 52
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted8 Jun 2026
- Study start6 Jul 2026
- Primary completion29 Jan 2029 (estimated)
- Study completion29 Jan 2029 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Metabolic Dysfunction-Associated Steatohepatitis (MASH)Studies of the same condition, open and under way.
- More trials run by Regeneron PharmaceuticalsThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 150 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Regeneron Pharmaceuticals
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Clinical Trial Management, Study director, Regeneron Pharmaceuticals
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07631637
- Sponsor's protocol ID
- ALN-CIDEB-MASH-2603
- Other IDs
- 2026-525916-33-00
- Status last verified
- Oct 2026
- First submitted
- 1 Jun 2026
- Last updated
- 26 Oct 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: All Individual Patient Data (IPD) that underlie publicly available results will be considered for sharing.
Study at a glance
From the registry record, last updated by the sponsor on 26 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 2b, Randomized, Double-Blind, Placebo-Controlled Study of ALN-CIDEB in Adults With Fibrotic Metabolic Dysfunction-Associated Steatohepatitis (MASH)
- ClinicalTrials.gov ID
- NCT07631637
- Acronym / sponsor ID
- ALN-CIDEB-MASH-2603
- Keywords
- F2 or F3 MASH, Fibrotic MASH, Nonalcoholic Fatty Liver Disease (NAFLD), Metabolic dysfunction-Associated Steatotic Liver Disease (MASLD), Liver Inflammation, Liver Fibrosis, Cirrhosis
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 150 participants (estimated)
- Lead sponsor
- Regeneron PharmaceuticalsIndustry (pharma, biotech, devices)
- Study start
- 6 Jul 2026 (actual)
- Primary completion
- 29 Jan 2029 (estimated)
- Study completion
- 29 Jan 2029 (estimated)
- First posted
- 8 Jun 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study will test a Regeneron study drug called ALN-CIDEB to find out whether it may help treat a liver disease called MASH.
In this study, researchers are looking at the effect of ALN-CIDEB on reducing liver fat, liver injury, and liver scarring. The study will compare ALN-CIDEB with placebo to understand how well ALN-CIDEB works to lower the amount of fat in the liver.
The study is looking at:
- What side effects ALN-CIDEB might cause
- How well ALN-CIDEB works to change liver fat, liver injury, and liver scarring
- How the body and the liver change after having ALN-CIDEB, which can help researchers understand why ALN-CIDEB works better for some people than others
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| ALN-CIDEB Dose 1 | Experimental | Drug: ALN-CIDEB |
| ALN-CIDEB Dose 2 | Experimental | Drug: ALN-CIDEB |
| Placebo | Placebo comparator | Drug: Placebo |
Who may qualify
- Ages
- 18 to 75 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- A diagnosis of MASH documented in the participant's medical history, or a clinical suspicion of MASH based on non-invasive biomarkers and clinical risk factors, including having a history of 1 or more elements of metabolic syndrome as described in the protocol
- Screening percutaneous liver biopsy demonstrating a NAFLD Activity Score (NAS) ≥4 and fibrosis stage F2 or F3 as described in the protocol
- Has a FibroScan Aspartate aminotransferase (FAST) score >0.35 either at Screening Visit 1 or within approximately 3 months of Screening Visit 1 as described in the protocol
Key exclusion criteria (6 listed)
- Known chronic liver disease other than Metabolic dysfunction-Associated Steatotic Liver Disease (MASLD), as determined by the investigator as described in the protocol
- Prior or current suspected or known drug-induced liver injury within approximately 1 year prior to Screening Visit 1
- History of liver transplantation, current placement on a liver transplant list, or MELD score >12
- Known history of alcohol or other substance abuse within the last year or at any time during screening based on investigator's discretion and/or a score on the AUDIT questionnaire ≥8
- Prior current, or planned future use of a Glucagon-Like Peptide-1 (GLP-1) receptor agonist-based therapy or any medication approved for the treatment of MASH unless used at a generally stable dose and regimen since at least 3 months prior to Screening Visit 1 or the qualifying historical liver biopsy and throughout the screening period with no change to the dose or regimen anticipated during the treatment period as described in the protocol
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| ALN-CIDEBAdministered per the protocol | Drug | ALN-CIDEB Dose 1, ALN-CIDEB Dose 2 |
| PlaceboAdministered per the protocol | Drug | Placebo |
Primary outcome
Percent change from baseline in liver fat by Magnetic Resonance Imaging-derived Proton Density Fat Fraction (MRI-PDFF)
Time frame: At week 26
17 secondary outcomes
Resolution of MASH with no worsening of Nonalcoholic Steatohepatitis-Clinical Research Network (NASH-CRN) fibrosis on liver biopsy
Time frame: At week 52
Percent change from baseline in liver fat by MRI-PDFF
Time frame: At week 52
Achievement of a ≥30% reduction in liver fat by MRI-PDFF
Time frame: At week 52
Achievement of ≤5% liver fat by MRI-PDFF
Time frame: At week 52
Percent change from baseline in liver fat by MRI-PDFF for each dose level of ALN-CIDEB
Time frame: Up to week 52
Improvement of NASH-CRN Fibrosis Stage (F) by ≥1 with no worsening of MASH
Time frame: At week 52
Occurrence of Treatment-Emergent Adverse Events (TEAEs)
Time frame: Up to week 64
Severity of TEAEs
Time frame: Up to week 64
Change from baseline in FibroScan Controlled Attenuation Parameter (CAP)
Time frame: Through week 52
Change from baseline in FibroScan Liver Stiffness Measurement (LSM) by Vibration Controlled Transient Elastography (VCTE)
Time frame: Through week 52
Change from baseline in Aspartate Aminotransferase (AST)
Time frame: Up to week 64
Change from baseline in Alanine Aminotransferase (ALT)
Time frame: Up to week 64
Change from baseline in Enhanced Liver Fibrosis (ELF)
Time frame: Through week 52
Change from baseline in PRO-C3
Time frame: Through week 52
Change from baseline in ADAPT
Time frame: Through week 52
Change from baseline in NIS2+
Time frame: Through week 52
Percent change from baseline in liver fat by MRI-PDFF in genetic subpopulations
Time frame: At week 52
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 26 Oct 2026.
- Individual participant dataSharing planned: Yes. All Individual Patient Data (IPD) that underlie publicly available results will be considered for sharing.
Related trials for Metabolic Dysfunction-Associated Steatohepatitis (MASH)
RecruitingPhase 3
A Study Evaluating Efruxifermin in Subjects With Non-Cirrhotic Nonalcoholic Steatohepatitis (NASH)/Metabolic Dysfunction-Associated Steatohepatitis (MASH) and Fibrosis
NASH With Fibrosis, MASH With Fibrosis
RecruitingPhase 1
A Study of INI-822 in Healthy Volunteers and Participants With Metabolic Dysfunction-Associated Steatohepatitis (MASH) or Presumed MASH
Metabolic Dysfunction-Associated Steatohepatitis
RecruitingPhase 3
Trial to Evaluate ALN-CIDEB in Adults With Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD)
Metabolic Dysfunction-Associated Steatotic Liver Disease, MASLD
RecruitingPhase 3
A Pivotal Clinical Study to Investigate the Safety and Efficacy of Efimosfermin Compared With Placebo in Adult Participants With Compensated Cirrhosis Due to Metabolic Dysfunction-associated Steatohepatitis (MASH)
Metabolic Dysfunction-associated Steatohepatitis
RecruitingPhase 3
A Study to Investigate Safety and Efficacy of Efimosfermin Compared With Placebo in Adult Participants With Compensated Cirrhosis Due to Metabolic Dysfunction-associated Steatohepatitis (MASH)
Metabolic Dysfunction-associated Steatohepatitis
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Clinical Trial Management study director
Regeneron Pharmaceuticals
16 sites in 2 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing ALN-CIDEB in people with Metabolic Dysfunction-Associated Steatohepatitis (MASH), run by Regeneron Pharmaceuticals at 16 sites in 2 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 26 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 16 sites in United States, Puerto Rico. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Clinical Trials Administrator (844-734-6643, clinicaltrials@regeneron.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Percent change from baseline in liver fat by Magnetic Resonance Imaging-derived Proton Density Fat Fraction (MRI-PDFF) (time frame: At week 26). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 26 Oct 2026.