US FDA declines to approve PTC Therapeutics' rare genetic disorder drug

Aug 19 (Reuters) - The U.S. Food and Drug Administration has declined to approve PTC Therapeutics' PTCT.O drug to treat a rare genetic disorder with limited treatment options, the company said on Tuesday, sending its shares down over 5% in premarket trading.

The FDA, in its so-called Complete Response Letter, said the data did not provide substantial evidence of efficacy for the drug, vatiquinone, to treat Friedreich's ataxia and that a separate study is needed before resubmitting the application.

"We are of course disappointed by the FDA's decision to not approve vatiquinone," CEO Matthew Klein said, adding that data till date demonstrates the drug could be safe and effective for children and adults living with the disorder.

The company said it plans to meet with the FDA to discuss potential steps.

Friedreich's ataxia is a rare inherited disorder that affects the nervous system and the muscles, often leading to difficulty in walking, speech problems and heart complications.

The disease typically manifests in childhood or adolescence, with patients losing the ability to walk approximately 10 to 15 years after onset.

The company's application was based on data from a late-stage trial and two long-term studies that showed vatiquinone slowed disease progression by up to 50% over three years in children and adults with Friedreich’s ataxia, while being well tolerated across all age groups.

But the drug did not meet its main goal in the late-stage trial of significantly reducing disease progression.