As reported on Inside Precision Medicine, scientists in Germany have made an exciting discovery that could help children with a very rare and serious illness called Leigh syndrome (LS). This disease affects the brain and muscles because the body’s “power plants”—called mitochondria—don’t work correctly. This makes it hard for the body to create the energy it needs to grow and move. Currently, about 1 in 36,000 children are born with this condition, and until now, there was no real treatment.
To find a solution, researchers at University Hospital Düsseldorf decided to look at over 5,600 existing medicines to see if any of them could be “repurposed.” Instead of inventing a brand-new drug, they wanted to see if a medicine we already know is safe could help these patients.
An Unexpected Winner
After a massive search, they found a surprising candidate: sildenafil. While many people know this as the active ingredient in Viagra, doctors already use it safely in children for other heart and lung issues.
When the scientists tested the drug on “mini-brains” grown from patient cells and in animal models, the results were amazing:
- Brain health improved: The drug helped brain cells develop more normally.
- More energy: Animals with the disease had stronger muscles and better breathing.
- Longer life: The animals lived longer when given the medicine.
Real-World Success
The researchers then gave sildenafil to six people with Leigh syndrome, ranging from a baby to a 38-year-old. The results in these real patients were life-changing. One child went from being able to walk 500 meters to walking 5,000 meters—ten times their original distance! Other patients saw their seizures stop or no longer suffered from “metabolic crises,” which are dangerous health crashes caused by the disease.
The medicine was so successful that European health officials have given it “orphan drug” status. This is a special label that makes it easier and faster for the drug to be approved for this specific rare disease. While more testing is needed, this is the first big step toward a real treatment for Leigh syndrome.
Important Quotations
“For example, in the case of a child undergoing sildenafil treatment, the walking distance increased tenfold, from 500 to 5000 meters.”
— Markus Schuelke, MD
“Sildenafil was prioritized for further testing given that it already has a known safety profile in children.”
“In another child, the therapy completely suppressed metabolic crises that occurred almost monthly, while another patient no longer suffered from epileptic seizures.”
— Markus Schuelke, MD
“The European Medicines Agency has granted sildenafil orphan drug status, meaning it can undergo a simplified approval process intended to support the development of therapies for rare diseases.”
