Neuren Pharmaceuticals Stock Soars 17.5% After Record DAYBUE Sales Growth and Royalty Forecast Boost

SYDNEY — Shares of Neuren Pharmaceuticals Ltd surged 17.52% on Wednesday, closing at $21.87, after the Australian biopharmaceutical company reported record second-quarter net sales for its flagship Rett syndrome treatment DAYBUE and raised its full-year royalty income projections.

The stock's single-day gain marked one of the sharpest rallies for Neuren in recent months, adding more than $3 a share and pushing the company's market value sharply higher as investors responded to accelerating demand for the drug in the United States and fresh signs of international expansion.

Record Quarter for DAYBUE

Neuren said second-quarter 2026 net sales of DAYBUE, known chemically as trofinetide, reached $125 million, an increase of 30% from the same period a year earlier and 24% higher than the first quarter of 2026. The figure represents the highest quarterly sales total since the drug's U.S. launch in 2023, according to the company.

The sales are generated in the U.S. by Acadia Pharmaceuticals, Neuren's commercial partner, which markets and distributes DAYBUE under a licensing agreement. Acadia attributed the bulk of the sales growth to higher patient volume rather than pricing changes, pointing to strong uptake of DAYBUE STIX, a new powder formulation of the drug that became broadly available across the U.S. beginning in early April.

By the end of the second quarter, roughly 40% of all U.S. DAYBUE patients were using the STIX formulation, the company said. Of that demand, about 45% came from new or returning patients, a sign that the reformulated product is helping draw patients who had not previously started or had discontinued treatment.

Royalty Income Climbs

Because Neuren earns royalties and milestone payments tied to U.S. sales rather than manufacturing or selling the drug directly, the surge in DAYBUE demand translated directly into higher income for the company. Neuren reported royalty income of $12.9 million for the second quarter, up 34% from a year earlier and 24% from the first quarter of 2026.

Following the results, Acadia raised its full-year 2026 net sales guidance for DAYBUE in the U.S. to a range of $480 million to $510 million, up from its previous forecast of $460 million to $490 million. The revised outlook implies a corresponding increase in the royalty income Neuren expects to collect for the year, a detail that analysts said was central to Wednesday's rally.

Rett syndrome is a rare genetic neurological disorder that primarily affects girls, causing severe impairments in language, movement and other functions. DAYBUE, approved by the U.S. Food and Drug Administration in 2023, was the first treatment cleared specifically for the condition and remains Neuren's principal commercial product.

European Expansion on Track

Wednesday's announcement also highlighted regulatory progress in Europe, where Neuren has been working to secure marketing authorization for trofinetide. In late June, the European Medicines Agency's Committee for Medicinal Products for Human Use adopted a favorable opinion recommending approval of the drug, moving Neuren closer to its first commercial launch outside the United States.

Pending formal approval from the European Commission, Neuren said it expects a commercial launch in Germany as early as the fourth quarter of 2026. A successful European rollout would open a new revenue stream through additional milestone and royalty payments, further diversifying the company's income beyond the U.S. market.

In Japan, a separate pivotal trial of trofinetide remains on schedule, with results expected between September and November of this year. Neuren has said it intends to pursue a regulatory submission in Japan in 2027 if the data support approval, representing a third major market opportunity for the drug.

Pipeline Beyond DAYBUE

Beyond its commercial product, Neuren continues to advance an experimental compound, NNZ-2591, through clinical development for a range of rare neurodevelopmental disorders, including Phelan-McDermid syndrome, Angelman syndrome, Pitt Hopkins syndrome and Prader-Willi syndrome. A Phase 3 trial evaluating NNZ-2591 in children with Phelan-McDermid syndrome is currently enrolling patients, following earlier Phase 2 results that showed improvements across measures of behavior, communication and quality of life, according to data published in peer-reviewed research.

Company filings show additional data readouts from the NNZ-2591 program are expected over the coming year, which analysts say could serve as future catalysts for the stock independent of DAYBUE's commercial trajectory.

Market Reaction

Wednesday's jump extended a period of strong performance for Neuren shares, which had already been trending higher in recent weeks on optimism tied to the European regulatory review and steady U.S. sales momentum. The stock's advance came as broader U.S. and Australian equity markets also rallied, with major indexes including the S&P 500 and the ASX both touching record levels amid easing geopolitical tensions and a pullback in oil prices.

Neuren, headquartered in Melbourne, develops therapies for neurodevelopmental disorders rooted in genetic mutations or brain injury, with a scientific focus on insulin-like growth factor 1, a protein that plays a critical role in brain development. The company licenses trofinetide to Acadia for the North American market while retaining rights to develop and commercialize its pipeline compounds in other regions.

Trading in Neuren shares on the Australian Securities Exchange, where the company is primarily listed under the ticker NEU, also reflected the rally, with volumes running well above recent averages as investors repositioned around the improved sales and royalty outlook.

The company's next scheduled financial update is expected to provide further detail on the pace of the European launch, progress in the Japanese trial and additional data from its NNZ-2591 clinical programs, all of which investors are likely to watch closely as potential drivers of the stock in the months ahead.