Sobi to Acquire Arthrosi Therapeutics for $950 Million, Expanding Gout Pipeline
Stockholm, Sweden – December 14, 2025 – Sobi® (STO:SOBI) today announced a definitive agreement to acquire Arthrosi Therapeutics, Inc., a privately held late-stage biotechnology company specializing in the development of novel gout treatments. The acquisition, valued at an initial $950 million (approximately SEK 9.1 billion) plus potential milestone payments of up to $550 million (approximately SEK 5.3 billion), significantly strengthens Sobi’s position in the gout therapy market and promises to accelerate its long-term growth.
Expanding Sobi’s Gout Franchise with Pozdeutinurad
The core of the deal is pozdeutinurad (AR882), an investigational, once-daily oral URAT1 inhibitor currently undergoing evaluation in two fully enrolled global Phase 3 clinical trials. These trials, known as REDUCE 1 and REDUCE 2, are designed to assess the drug’s efficacy in managing progressive and tophaceous gout, with pivotal data anticipated in 2026. According to a company release, pozdeutinurad is designed to complement Sobi’s existing gout pipeline, offering a potentially best-in-class treatment option for patients who haven’t achieved adequate symptom control with first-line therapies.
“The acquisition of Arthrosi allows us to expand our gout pipeline with a highly differentiated new asset,” stated Guido Oelkers, President and CEO of Sobi. “Pozdeutinurad has the potential to become the therapy of choice for patients who have progressive gout with persistent and unresolved symptoms despite first-line therapy. The product has the potential to materially accelerate our growth until the mid 2030s, and beyond.”
A Transformative Opportunity for Gout Patients
Arthrosi’s Founder and CEO, Litain Yeh, Ph.D., echoed this sentiment, stating, “We are thrilled to join forces with Sobi and look forward to working together to ensure a seamless transition as they advance pozdeutinurad towards pivotal data and potential regulatory filings. We believe that Sobi’s global expertise in commercialisation will accelerate our shared mission to deliver pozdeutinurad’s potentially transformative benefits for individuals living with gout.”
Financial Details and Transaction Timeline
Under the terms of the agreement, Sobi will make an upfront cash payment of $950 million to acquire Arthrosi, with an additional $550 million contingent upon achieving specific clinical, regulatory, and sales milestones. The transaction is subject to customary closing conditions and is expected to be finalized in the first half of 2026.
Sobi intends to finance the upfront payment primarily through debt, utilizing existing credit facilities and securing a new credit facility from Handelsbanken and Danske Bank. Analysts predict the acquisition will be “highly accretive” to Sobi’s mid- to long-term growth and margin trajectory. Barclays Bank PLC served as Sobi’s financial advisor, while McDermott, Will & Schulte provided legal counsel.
Understanding Pozdeutinurad’s Potential
Pozdeutinurad (AR882) has demonstrated promising results in Phase 2 studies, exhibiting a sustained reduction in serum uric acid levels, dissolution of tophi (urate crystal deposits), and a favorable safety profile. The ongoing Phase 3 REDUCE 1 and REDUCE 2 trials are twelve-month, randomized, double-blind, placebo-controlled studies evaluating the drug’s ability to lower sUA in patients with progressive and tophaceous gout.
Arthrosi Therapeutics, based in San Diego, California, is dedicated to the development of pozdeutinurad as a next-generation URAT1 inhibitor. The rights to pozdeutinurad in Greater China are held by ApicHope.
Addressing the Unmet Need in Gout Treatment
Gout, the most prevalent form of inflammatory arthritis, arises from elevated uric acid levels that accumulate in joints and tissues, causing painful flares. Untreated gout can progress to a chronic condition leading to joint damage, reduced mobility, and tophi formation. While initial treatments focus on lowering uric acid, many patients experience suboptimal results or fail to respond, highlighting the need for innovative therapies. Uncontrolled gout is also linked to increased risks of kidney disease and cardiovascular complications, emphasizing the importance of effective management.
Investor Conference Call
Investors, analysts, and media are invited to participate in a conference call on December 15th at 08:00 CET to discuss the acquisition in detail. The presentation will be available live here and archived on the Sobi website. Dial-in details are as follows:
- Sweden: +46 8 5051 0031
- United Kingdom: +44 207 107 06 13
- United States: +1 631 570 56 13
- Other Countries
About Sobi
Sobi is a global biopharmaceutical company focused on unlocking the potential of innovative therapies for individuals with rare diseases. With approximately 1,900 employees worldwide and 2024 revenues of SEK 26 billion, Sobi is committed to transforming the lives of patients. Sobi’s share (STO:SOBI) is listed on Nasdaq Stockholm. More information can be found at sobi.com and on LinkedIn. .
