Leigh syndrome is a rare genetic disorder where cells cannot produce enough energy to function properly. This causes the brain and muscles to deteriorate, leading to seizures, muscle weakness, paralysis, and delayed development. Currently, there is no approved drug treatment for this condition, which affects about one in 36,000 children.
Researchers at Charité University in Berlin tested whether sildenafil—a drug commonly used to treat erectile dysfunction in adults and pulmonary hypertension in infants—could help Leigh syndrome patients. The study, published in the journal Cell, tracked six patients ranging from 9 months to 38 years old who received continuous sildenafil treatment.
Measurable improvements within months
Within a few months, most patients showed stronger muscles and faster recovery from metabolic crises—sudden worsening of the disease caused by energy metabolism overload. One child's walking distance increased tenfold, from 500 to 5,000 metres. Another child who previously experienced seizures nearly every month had them completely suppressed. A third patient regained the ability to walk without seizures occurring.
Why the sample is so small
This study involved only six patients because Leigh syndrome is extremely rare, making large-scale trials very difficult to conduct. Researchers must collaborate across multiple hospitals and countries just to find enough patients to study. The small size means these results are promising but not yet definitive—larger studies are needed to confirm whether sildenafil consistently helps across more patients.
Important next steps for families
- If your child has been diagnosed with Leigh syndrome, ask your paediatrician whether sildenafil trials are available in Singapore or whether you can access them through international networks.
- Keep detailed records of your child's symptoms and any changes—this information will help doctors determine if treatment is working.