
Microscopic image of a 3D brain model, as used in the study
(red: neural progenitor cells; blue: neurons).
Image Credit: © HHU / Stephanie Le, AG Prigione
Scientific Frontline: "At a Glance" Summary: Sildenafil as a Therapy for Leigh Syndrome
- Main Discovery: Researchers identified the repurposed drug Sildenafil as a highly promising and effective treatment capable of improving the disease course of Leigh Syndrome, a severe and previously untreatable mitochondrial disorder affecting brain energy metabolism.
- Methodology: The international research consortium derived induced pluripotent stem cells from patient skin cells to cultivate 3D brain organoids and nerve networks, subsequently utilizing these models to screen a comprehensive library of over 5,500 approved drugs and molecules.
- Key Data: Affecting roughly one in 36,000 live births, Leigh Syndrome had no approved treatments until this study screened 5,500 compounds and successfully administered the leading candidate, Sildenafil, to six human patients, all of whom demonstrated rapid recovery from critical episodes and increased muscular strength.
- Significance: Because Sildenafil already possesses a well-documented long-term safety profile for treating pulmonary hypertension in infants, this discovery bypasses standard early-phase toxicity hurdles, offering an immediate and safe therapeutic intervention for a fatal childhood neurodevelopmental disease.
- Future Application: The European Medicines Agency has officially granted Sildenafil an Orphan Drug Designation, enabling the SIMPATHIC research consortium to initiate a multinational, placebo-controlled clinical trial aimed at securing formal regulatory approval for widespread clinical use.
- Branch of Science: Pediatric Neurology, Cellular Biology, and Molecular Pharmacology.
- Additional Detail: The study represents the largest drug screening process ever conducted specifically for Leigh Syndrome, successfully overcoming the traditional lack of accurate cellular and animal models that historically hindered rare disease research.








