Three selected reports cover the randomized Barth syndrome study, follow-up of the same cohort, and a separate primary mitochondrial myopathy trial. They do not cover every indication or replace the product-specific regulatory record.123
Bottom line from this bounded source set
The randomized Barth syndrome study did not meet its two primary endpoints; later uncontrolled follow-up reported improvements. The larger MMPOWER-3 trial in primary mitochondrial myopathy also missed its primary endpoints. These populations and study designs must be considered separately.123
Reviewed study record
TAZPOWER: randomized and early extension results
Design
A blinded placebo-controlled crossover trial was followed by an open-label extension.1
Population
Twelve participants with Barth syndrome entered the randomized study; ten entered the extension and eight reached 36 weeks.1
Outcomes reported
Neither primary endpoint was met in the randomized period. Walking distance and reported fatigue improved during the uncontrolled extension.1
Limitations
The extension lacks a concurrent placebo group and has attrition. Its changes cannot be interpreted as another randomized treatment effect; the abstract does not provide a detailed harms assessment.1
Reviewed study record
TAZPOWER: longer follow-up of the same cohort
Design
An open-label extension followed participants for up to 168 weeks.2
Population
Ten participants entered the extension; eight reached the week-168 visit.2
Outcomes reported
The authors reported improvements in walking distance and fatigue assessments. Injection-site reactions were the most common adverse events.2
Limitations
This is follow-up of TAZPOWER, not an independent trial. Selection, attrition and absence of concurrent controls limit attribution and generalizability.2
Reviewed study record
MMPOWER-3: primary mitochondrial myopathy
Design
A randomized, blinded, placebo-controlled phase 3 trial assessed 24-week outcomes.3
Population
The study randomized 218 participants with genetically confirmed primary mitochondrial myopathy.3
Outcomes reported
Neither walking distance nor fatigue met the primary efficacy endpoint. Most reported adverse events were mild or moderate.3
Limitations
This is a different disease population from Barth syndrome. Overall null results cannot be replaced by favorable exploratory subgroup findings.3
No registered Crossref update in the reviewed snapshotChecked September 15, 2026 for DOI 10.1038/s41436-020-01006-8. This bounded result is not proof that the publication has never been corrected or retracted. Open the pinned Crossref work endpoint ↗
No registered Crossref update in the reviewed snapshotChecked September 15, 2026 for DOI 10.1016/j.gim.2024.101138. This bounded result is not proof that the publication has never been corrected or retracted. Open the pinned Crossref work endpoint ↗
No registered Crossref update in the reviewed snapshotChecked September 15, 2026 for DOI 10.1212/wnl.0000000000207402. This bounded result is not proof that the publication has never been corrected or retracted. Open the pinned Crossref work endpoint ↗