Shionogi agrees to buy IntraBio for $2 billion to add rare disease drug Aqneursa

Shionogi agreed on 5 October 2026 to buy IntraBio, the company behind the rare disease drug Aqneursa, for $2 billion in cash ¹. IntraBio was founded in Oxford, UK, and moved its headquarters to Austin, Texas, at the end of 2023 ².

The deal terms

IntraBio will become a wholly owned subsidiary of Shionogi's US division, which is based in New Jersey ¹. Shionogi said it will review what the purchase does to its financial outlook for the current fiscal year, which ends next March ¹. Completion is scheduled for between November and December ².

The asset is Aqneursa (levacetylleucine), which came out of University of Oxford research ¹². The drug was approved in the US in 2024 for the neurological manifestations of Niemann-Pick disease type C (NPC), a condition that affects about 1 per million people in the US ¹². In a clinical trial, patients taking it scored better on an assessment of movement disorders, and that evidence supported the 2024 approval ¹. IntraBio then showed a similar benefit in ataxia-telangiectasia (A-T), a more common inherited neurodegenerative disorder, and won clearance there in September, making Aqneursa the first therapy approved for A-T ¹². Europe approved the drug for NPC earlier this year, and the A-T indication is under review there ².

IntraBio had sales of $68 million in 2025, according to Shionogi ¹. The price therefore rests on more than current revenue: the A-T label is weeks old in the US and still pending in Europe ¹².

What it means for the market

The purchase extends a deliberate move by Shionogi away from its base in anti-infectives ². It follows the acquisition of Tanabe Pharma's Radicava range for amyotrophic lateral sclerosis, which makes around $700 million in annual global sales ². Shionogi also completed a $1 billion takeover of Torii Pharma, Japan Tobacco's pharmaceutical subsidiary, last year ². Its US portfolio already includes the COVID-19 medicine Xocova and a treatment for complicated urinary tract and hospital-acquired respiratory infections ¹.

"The planned acquisition of IntraBio actively demonstrates Shionogi's solid commitment to building a leading global rare disease business," said Isao Teshirogi, Shionogi's chief executive ².

For rare disease biotechs, the deal shows a Japanese buyer willing to pay cash for a privately held company with a recently expanded label and modest sales. For Shionogi, a second commercial rare neurology product sits alongside a pipeline that, once the deal closes, includes clinical-stage candidates in Pompe disease and Fragile X syndrome ². The Fragile X programme, which came from the 2020 buyout of Tetra Therapeutics, is in a Phase 3 trial ¹. Shionogi also pointed to "additional early-stage rare neurodegenerative disease programs recently added to the pipeline" ¹.

Caveats

IntraBio is private and does not disclose its own sales, so the 2025 revenue figure comes from Shionogi's description of the deal ². The European A-T application has not yet been decided ². Shionogi has not yet said how the acquisition will change its forecast for the fiscal year to March ¹. The deal is due to complete between November and December ².