Ultragenyx’s GTX-102 failure erases pipeline sales expectations

Ultragenyx Pharmaceutical Inc. (NASDAQ: RARE) shares have fallen 44% after the rare-disease drugmaker said its Phase 3 Aspire trial of apazunersen (GTX-102) in Angelman syndrome failed to meet its primary and key secondary endpoints. The setback has prompted most analysts to remove GTX-102 revenue from their forecasts, dealing a blow to a pipeline asset that had been expected to reach the market in 2027.

The impact is increasingly visible in Ultragenyx’s longer-term revenue outlook. Visible Alpha consensus now puts Ultragenyx’s total revenue for 2027 at $928 million, down from $965 million previously, while the 2028 forecast has fallen to $1.1 billion from $1.3 billion. By 2033, analysts now expect revenue of $1.9 billion, compared with $2.9 billion before the trial result, a reduction of almost $1 billion. The widening gap in later years reflects the loss of GTX-102’s expected contribution as analysts reset the drug’s revenue outlook to zero.

The pipeline setback was accompanied by a more positive development in Ultragenyx’s commercial portfolio. On the same day as the Aspire results, the FDA confirmed that Genglycos, the biotech’s newly approved gene therapy for glycogen storage disease type Ia (GSDIa), qualifies for a rare pediatric disease priority review voucher.

Visible Alpha consensus expects Genglycos to generate $12 million in revenue in 2026, rising to $61 million in 2027, its first full year on the market. Sales are forecast to reach peak global revenue of $310 million in 2033 before declining as patent protection expires and generic competition emerges. While the launch provides a new source of growth, its expected contribution remains well below the revenue opportunity analysts had previously assigned to GTX-102.

This article was published by Visible Alpha, part of S&P Global Market Intelligence and not by S&P Global Ratings, which is a separately managed division of S&P Global.