Neuren Pharmaceuticals has reached a major milestone in the global commercialisation of trofinetide after the European Commission granted marketing authorisation for DAYBU to treat neurobehavioural symptoms associated with Rett syndrome.
The approval makes DAYBU the first and only authorised treatment for Rett syndrome in the European Union, extending access to patients aged five years and older across all 27 EU member states as well as Iceland, Liechtenstein and Norway.
For the Melbourne-based biotechnology company, the decision represents both an important advance for families affected by the rare neurological disorder and a potentially material commercial catalyst under its licensing arrangement with Acadia Pharmaceuticals.
Acadia, which holds Neuren’s exclusive worldwide licence to develop and commercialise trofinetide, has previously indicated that it expects to launch DAYBU in Germany in early in the fourth quarter of 2026.
Neuren chief executive Jon Pilcher said the approval was especially meaningful given the absence of an approved Rett syndrome treatment in Europe until now.
“We are delighted for the Rett syndrome community in Europe, who, until now, have had no approved treatment for this devastating condition,” Pilcher said.
“The European Commission’s approval of DAYBU is particularly rewarding for Neuren given our long-standing commitment to developing therapies for serious neurological disorders with profound unmet need.”
Rett syndrome is a severe genetic neurodevelopmental condition that predominantly affects girls and can lead to profound impairments in communication, motor function and everyday functioning. The European approval allows DAYBU to be marketed for the treatment of its neurobehavioural symptoms, creating a new treatment option for patients and families across the region.
The decision also brings financial significance for Neuren. Under its European licence agreement with Acadia, Neuren is entitled to receive US$35 million following the first commercial sale of DAYBU in Europe. It could also receive up to US$170 million in sales milestone payments as annual net sales reach escalating thresholds, alongside tiered royalties ranging from the mid-teens to the low 20 per cent range.
DAYBUE oral solution is already approved for Rett syndrome in the United States, Canada and Israel, while DAYBUE STIX powder has been approved by the US Food and Drug Administration. Trofinetide is not approved for sale in Australia.
The European authorisation comes as Neuren continues to advance its broader pipeline of therapies for serious neurological disorders. Its investigational candidate NNZ-2591, also known as ercanetide, is in clinical development for several rare neurodevelopmental conditions, including Phelan-McDermid syndrome, Pitt Hopkins syndrome and Angelman syndrome.
Neuren is also developing NNZ-2591 for hypoxic ischaemic encephalopathy, a form of brain injury that can occur before or shortly after birth. The company is currently running its Phase 3 Koala trial, a randomised, double blind and placebo-controlled study assessing NNZ-2591 in children aged three to 12 years with Phelan-McDermid syndrome, alongside a 52-week open-label extension study.
