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A Phase 2b Study of Zagociguat in Patients With MELAS

Phase 2b Randomized, Double-blind, Placebo-controlled Crossover Study Evaluating the Efficacy and Safety of Zagociguat in Participants With MELAS (PRIZM)

Status
Completed
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT06402123
Acronym
PRIZM
Enrollment
43
Registered
2024-05-07
Start date
2024-09-10
Completion date
2026-06-29
Last updated
2026-07-07

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Mitochondrial Encephalopathy, Lactic Acidosis and Stroke-Like Episodes (MELAS Syndrome)

Keywords

MELAS

Brief summary

PRIZM is a Phase 2b randomized, double-blind, placebo-controlled, 3-treatment, 2-period, crossover study evaluating the efficacy and safety of oral zagociguat 15 and 30 mg vs. placebo when administered daily for 12 weeks in participants with genetically and phenotypically defined MELAS.

Detailed description

The goal of this clinical trial is to learn about the effectiveness of zagociguat in patients with MELAS. The main questions it aims to answer are: * Does zagociguat improve fatigue in patients with MELAS? * Does zagociguat improve cognitive performance in patients with MELAS? * What is the safety and tolerability profile of zagociguat? The PRIZM study is evaluating 2 dose levels of zagociguat in a crossover design consisting of two 12-week treatment periods separated by a 4-week washout. Patients will be screened and if eligible, randomly assigned either to receive placebo in period 1 followed by active drug in period 2 OR to receive active drug in period 1 followed by placebo in period 2. Study medication is a once daily oral tablet and will be provided at the clinic and/or shipped to the participant's home. Clinic visits will occur at screening and Week 1 and Week 12 of each treatment period. Visits at Week 4 and Week 8 of both crossover periods will either be in clinic or optionally at the participant's home. Study assessments will be conducted weekly on a phone app and a separate tablet and additional assessments will be conducted during visits. Patients who complete the study will be eligible for an open label extension study.

Interventions

Once-daily oral tablets

DRUGzagociguat 30mg

Once-daily oral tablets

DRUGPlacebo

Once-daily oral tablets

Sponsors

Tisento Therapeutics
Lead SponsorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Masking description

This a double-blind study in which investigators, participants/caregivers, Sponsor, and all study personnel will be blinded.

Intervention model description

Randomized, double-blind, placebo-controlled, 3-treatment, 2-period, incomplete-block, 4-sequence, crossover study. Eligible patients will be randomized to 1 of 4 crossover treatment sequences. Each treatment period will last 12 weeks, separated by a 4-week washout period.

Eligibility

Sex/Gender
ALL
Age
18 Years to 75 Years
Healthy volunteers
No

Inclusion criteria

1. Signed consent form. 2. 18 to 75 years of age. 3. Diagnosed with MELAS based on the presence of each of the following criteria: 1. A documented pathogenic variant in a mitochondrial DNA (mtDNA) gene. 2. History of one or more stroke-like episodes (SLEs) with magnetic resonance imaging (MRI) findings consistent with stroke-like lesions. 4. Scores below normal average on the iDSST and GMLT. 5. Reports fatigue due to MELAS. 6. Can complete at least 1 sit-to-stand in the 30-second test interval. 7. Completes all at-home weekly activities independently during the Screening Period (caregiver may help set up device/app, log-in, etc.). 8. Other criteria per the protocol.

Exclusion criteria

1. Systolic blood pressure (BP) 90 mmHg or diastolic BP 60 mmHg. 2. Orthostatic hypotension when measured after standing from a semi-recumbent/supine position. 3. Active cancer significant enough to confound the results of this study. 4. Severe gastrointestinal dysmotility that may impact participation. 5. Recent history (within last 6 months) of platelet dysfunction, hemophilia, von Willebrand disease, coagulation disorder, other bleeding diathesis condition(s), or significant, nontraumatic bleeding episodes. 6. History of spontaneous fracture(s) that in the investigator's opinion represents a safety risk for trial participation. 7. Current use of prohibited medication (reviewed by investigator). 8. Any medical or other condition that the investigator thinks would preclude study participation. 9. Other

Design outcomes

Primary

MeasureTime frameDescription
• PROMIS Fatigue MELAS Short Form scores• Groton Maze Learning Test scores • International Digit Symbol Substitution Test scoresWeeks 9 through 12 of each treatment periodThese measures are a patient reported questionnaire on MELAS-specific fatigue and 2 cognitive performance tests. These 3 outcome measures will be combined using a global statistical test.
Incidence of Treatment-emergent Adverse Events (TEAEs)Weeks 1 through washout for treatment period 1 and Weeks 1 through follow-up for treatment period 2TEAEs are any untoward event that may or may not be related to study medication.

Secondary

MeasureTime frameDescription
Number of repetitions completed during the 30-second sit-to-stand testWeek 12Leg strength and exercise intolerance
PROMIS Cognitive Function MELAS Short Form (PCFM-SF) scoreWeek 12Patient-reported questionnaire on MELAS-specific cognitive function
Plasma concentrations of GDF-15Week 12Measure of disease pathophysiology
Memory composite scores (One Card Learning and One Back Tests) for Week 9 through 12Week 9 through 12Test of memory

Countries

Australia, Canada, Germany, Italy, United Kingdom, United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Jul 8, 2026