Santhera closes on first approval for DMD drug vamorolone

Swiss biotech Santhera is on the brink of its first regulatory approval for Duchenne muscular dystrophy treatment vamorolone, after getting a positive opinion on the drug from the EMA’s human medicines committee.

The CHMP has recommended approval of the drug – under the Agamree trade name – for the treatment of DMD patients aged four years and older. Santhera said that, subject to full approval in the EU, which generally follows a CHMP endorsement by a few weeks, it is now planning a first launch in Germany in the first quarter of next year.

“Agamree could become the first drug fully approved by the European Medicines Agency […] for the treatment of patients with DMD,” said the company in a statement, noting that vamorolone has also been filed in the US, with a decision from the FDA due later this month.

The CHMP recommendation marks a turnaround in fortunes for Santhera, which was forced to slash staff and restructure its operations after its first DMD candidate, idebenone, failed a phase 3 trial in 2020. Vamorolone was licensed from US biotech ReveraGen BioPharma in 2020, shortly after Santhera abandoned the development of idebenone for DMD.

“We are thrilled about the CHMP’s positive opinion, which recognises the urgent medical need for an effective and well-tolerated treatment for this devastating disease,” said Santhera’s chief executive, Dario Eklund (pictured above).

“We can now execute on our plans to ensure Agamree is made available to patients in the EU as soon as the European Commission marketing authorisation is received,” he added.

The approval recommendation is based largely on the phase 2b VISION-DMD study, in which vamorolone had positive effects on mobility measures like the six-minute walk (6MWT) test and time to stand (TTSTAND) velocity compared to placebo at 24 weeks, with the benefits maintained out to 48 weeks, in DMD patients aged four to seven.

Moreover, boys treated with vamorolone on average maintained growth similar to those treated with placebo, whilst those treated with corticosteroid prednisone – a standard therapy for DMD – on average experienced growth stunting.

Patients who switched from prednisone to vamorolone after 24 weeks were, on average, able to resume growing in height over the remainder of the study, according to Santhera.

Trials of the drug are also ongoing in younger DMD patients aged two to four, as well as the seven to 18 age bracket, and also in patients with Becker muscular dystrophy (BMD), which is less common than DMD and tends to cause milder symptoms.

If approved by the FDA, vamorolone will be commercialised in the US by Catalyst Pharmaceuticals, which licensed rights to the drug for $90 million upfront earlier this year. Santhera has previously estimated that the drug could make sales of more than $500 million a year if approved in the US and Europe.