EU rules PTC’s Duchenne drug can stay on the market

Going against the advice of its own advisors, the European Commission has said that PTC Therapeutics’ Translarna therapy for Duchenne muscular dystrophy (DMD) should stay on the market.

It has asked the Committee for Medicinal Products for Human Use (CHMP) to take a third look at the data supporting the use of Translarna (ataluren) for DMD, despite the fact that the panel adopted a negative opinion on two prior occasions.

William Blair analyst Sami Corwin said to her knowledge this is an unprecedented move and raises the chances that the CHMP will take a positive view on the drug and renew its conditional marketing authorisation. In the meantime, Translarna remains on the market and available to patients with DMD in the EU.

“We believe the EC’s decision is likely reflective of intense backlash from physicians and patient advocates who have no other therapeutic options and view Translarna as a safe and effective treatment,” she added.

The drug had sales of $356 million last year, accounting for more than a third of PTC’s total revenues of around $938 million, but the company has paused its earlier guidance of $600-$850 million in 2024 revenues due to the uncertainty surrounding Translarna.

Corwin said PTC’s management has said it believes that its clinical trials, including the placebo-controlled Study 041, and STRIDE patient registry support the risk/benefit profile of Translarna, which has been on the market in the EU for more than a decade and was the first DMD treatment ever to be approved for marketing.

Last year, the CHMP said that Study 041 had failed to demonstrate Translarna’s efficacy, despite meeting its primary endpoint with a significant reduction in patients’ decline in motor function, as measured by the 6-minute walk distance (6MWD) test.

The trial failed to show that the medicine was effective in patients with a progressive decline in their ability to walk, who were expected to have greater benefit from Translarna treatment compared with other patients included in the study, undermining the results, according to the panel. It also concluded that the data from the STRIDE registry was not reliable, reiterating its negative opinion in January after PTC appealed.

In a statement, PTC’s chief executive Matthew Klein said the EC’s decision is a “big win for boys and young men with nonsense mutation Duchenne muscular dystrophy in Europe,” adding: “We look forward to working collaboratively with CHMP on next steps once they are defined.”