Crystalys Therapeutics

Biotech · Pharmaceuticals

Funding

Crystalys Therapeutics banks $130M Series B for gout drug's Phase 3 push

This marks the company's second nine-figure raise within a year, a rare show of conviction for a single drug asset in venture biotech.

• Crystalys Therapeutics closed an oversubscribed $130 million Series B led by Frazier Life Sciences to fund late-stage global trials and commercial prep for dotinurad, an oral gout drug.
• Crystalys is a San Diego biotech developing dotinurad, a once-daily oral inhibitor of URAT1, the kidney transporter that clears uric acid, aimed at gout patients who fail standard treatments.
• Dotinurad is already approved in Japan, China, the Philippines, Taiwan and Thailand after being licensed from Fuji Yakuhin; Crystalys acquired global rights from Urica Therapeutics in 2024 in exchange for 35% equity and a 3% royalty on future sales.
• The Series B follows a $205 million Series A raised in September 2025, giving Crystalys roughly $335 million in disclosed funding for a single drug candidate in under a year.
• Proceeds fund two Phase 3 registration trials, RUBY and TOPAZ, comparing dotinurad against allopurinol, plus a Phase 2 AMETHYST study testing the drug in patients who don't respond to Amgen's Krystexxa.
• The raise comes months after Sobi paid $950 million upfront for rival URAT1 developer Arthrosi Therapeutics, signaling strong dealmaking interest in the gout treatment category.
• Back-to-back nine-figure rounds for one already-approved-elsewhere drug show biotech investors will still write large late-stage checks for de-risked assets, even as venture capital increasingly concentrates in AI.