Neuren’s DAYBUE Sales Rise 20% as Japan Trial Accelerates

Robust Q1 Sales Highlight DAYBUE Momentum

Neuren Pharmaceuticals (ASX:NEU) kicked off 2026 with a solid 20% increase in DAYBUE® (trofinetide) net sales, reaching US$101 million in the first quarter; the fastest year-on-year growth since late 2024. This surge translated into a 23% rise in royalties for Neuren, which earned US$10.4 million in Q1, underpinning confidence in the drug’s commercial trajectory. Acadia Pharmaceuticals, Neuren’s US partner, reaffirmed its full-year sales guidance of US$460–490 million, implying royalties of US$50–54 million for Neuren, assuming stable exchange rates.

Neuren CEO Jon Pilcher expressed optimism about the US market, noting that penetration remains at approximately 60% within Rett syndrome Centers of Excellence and just 28% in the broader community, suggesting room for growth. The company also highlighted the positive reception of the new DAYBUE STIX powder formulation, which launched on a limited basis in Q1 and became widely available in early April.

DAYBUE STIX Gains Early Traction with Caregivers

DAYBUE STIX, an FDA-approved powder form of trofinetide, has quickly garnered enthusiasm among healthcare professionals and caregivers. In Q1, over 250 prescriptions were written, with roughly 30% prescribed to treatment-naïve or previously discontinued patients. Caregiver satisfaction exceeded 80%, a promising sign for patient adherence and acceptance. This momentum builds on the broader US availability of the powder formulation, which aims to enhance dosing flexibility and convenience for Rett syndrome patients.

The encouraging early uptake aligns with a recent Delphi expert consensus panel recommendation endorsing DAYBUE as part of the standard of care for eligible Rett syndrome patients, potentially supporting wider clinical adoption and reimbursement discussions. This expert backing adds to the growing body of real-world evidence supporting trofinetide’s role in managing this rare neurological disorder. The evolving landscape around DAYBUE STIX follows the initial rollout and positive feedback reported in earlier months, reflecting sustained market interest US access to DAYBUE STIX.

Regulatory and Clinical Progress Outside the US

Beyond the US, Neuren’s partner Acadia is advancing regulatory and clinical milestones. The trofinetide trial in Japan has been accelerated, with topline results now expected between September and November 2026, ahead of the previous Q4 2026 to Q1 2027 window. This expedited timeline could open a significant new market if successful, as Japan represents a key region for rare disease therapies.

In Europe, the reexamination process for trofinetide’s marketing approval is due to conclude in June 2026. This follows Acadia’s formal request to the European Medicines Agency for reexamination after an initial refusal, which cited concerns over treatment effect and study design. The outcome of this process will be pivotal for Neuren’s European ambitions, potentially unlocking access to a substantial patient population currently underserved by approved treatments EU re-examination of trofinetide.

Pipeline Developments and Market Positioning

While DAYBUE remains Neuren’s commercial flagship, the company is progressing its second candidate, NNZ-2591, through Phase 3 trials targeting multiple neurodevelopmental disorders. This diversification aims to build a broader neurological portfolio beyond Rett syndrome and could provide future growth avenues. Meanwhile, Neuren’s royalty income from DAYBUE sales continues to provide robust cash flow to support ongoing R&D.

Neuren’s strategy hinges on leveraging the growing acceptance of trofinetide in the US, expanding international markets, and capitalising on new formulations like DAYBUE STIX to deepen market penetration. However, regulatory uncertainties in Europe and the outcome of the Japan trial remain key variables that could materially influence the company’s trajectory over the coming year.