EU mitochondrial myopathy
Mitochondrial myopathy trials: leading sites, investigators and clinical assessments
Updated 19 September 2026
European mitochondrial myopathy programs concentrate at a small group of specialist neuromuscular and mitochondrial centres. Fatigue and objective motor or muscle function are the most consistently used efficacy domains.
Sites
Five centres recur across late-stage mitochondrial disease programs
Repeated participation is concentrated in France and Italy, with the same institutions appearing across the sonlicromanol Phase III and KL1333 extension programs.
Investigators
Five recurrent investigators in the late-stage programs
These investigators are repeatedly named across the sonlicromanol Phase III and KL1333 extension programs.
Trial participation reflects recorded study experience, not current capacity, patient access or recruitment performance.
Assessments
Fatigue and motor function are the most consistent efficacy domains
The protocols repeatedly combine patient-reported symptoms with direct measures of physical function, while broader disease severity and biomarker measures usually support the main efficacy readout.
Previous trial findings
Findings from previous sonlicromanol trials
The sonlicromanol development history shows how endpoint choice evolved before the current Phase III study.
KHENERGY reported no significant improvement in gait, 6-minute walk, grip strength, 30-second sit-to-stand or NMDAS. The protocol notes that many participants were mildly affected and had normal baseline functional scores.
In KHENERGYZE, the primary attention analysis was not significant overall. Post-hoc analyses found stronger effects in participants with poorer baseline performance, including a significant attention-domain result at 50 mg twice daily.
KHENEREXT reported improvements from baseline in physical health, lower-limb strength, balance, pain and fatigue. Improvements observed at Week 52 persisted through Week 78 in participants who continued treatment.
KHENERFIN uses Neuro-QoL Fatigue and Five Times Sit-to-Stand as co-primary endpoints in adults with symptomatic m.3243A>G primary mitochondrial disease and measurable myopathy.
Source: CTIS trial records, protocols and filed results, reviewed 19 September 2026.