Crystalys raises $130M to advance late-stage gout drug dotinurad
What's the deal? Crystalys Therapeutics has raised $130 million in series B financing to advance its gout drug dotinurad through phase 3 trials and prepare for a potential commercial launch. Frazier Life SciencesDealroom has a profile for this one. Try Dealroom → led the round, with new investors Wellington Management, HBM Healthcare InvestmentsDealroom has a profile for this one. Try Dealroom →, Soleus CapitalDealroom has a profile for this one. Try Dealroom → and Cormorant Asset Management joining. Existing backers Novo HoldingsDealroom has a profile for this one. Try Dealroom →, SR OneDealroom has a profile for this one. Try Dealroom → and Catalys PacificDealroom has a profile for this one. Try Dealroom → also participated.
Why now? The raise comes less than a year after the San Diego company emerged from stealth with a $205 million series A in September 2025. "It was one of the fastest financings that I've ever participated in," chief executive officer James MackayDealroom has a profile for this one. Try Dealroom → told Fierce Biotech, crediting the earlier round for making holdouts "sit up and take notice."
What's the endgame? Dotinurad is a once-daily oral inhibitor of urate transporter 1 (URAT1), which helps the kidneys excrete uric acid — the buildup that causes gout's painful joint inflammation. The proceeds fund two registration-directed phase 3 trials, the phase 2 Amethyst study, and commercialization prep, extending Crystalys' runway "at least a year beyond the phase 3 data readouts."
The de-risked bet: Mackay calls dotinurad a "de-risked molecule" because it is already approved in Japan, China, the Philippines, Taiwan and Thailand. Originally developed by Japan's Fuji Yakuhin, Crystalys acquired the rights from Urica TherapeuticsDealroom has a profile for this one. Try Dealroom → in July 2024 in exchange for 35% of its equity and a 3% royalty on future sales.
The market gap: Existing first-line therapies leave roughly half of gout patients short of treatment goals, while second-line options remain limited by safety concerns or burdensome intravenous administration, leaving a significant unmet need.
The phase 3 Ruby and Topaz studies are already underway, comparing dotinurad with allopurinol in different gout populations after regulators allowed Crystalys to move directly into late-stage development based on Asian and earlier US clinical data.
The signal: "There's a massive unmet medical need in the second line space," Mackay said, and investors are betting on an approved molecule to fill it. With the biotech market "reasonably buoyant," he is weighing longer-term options, including an IPO.
Read more: Fierce Biotech, BioPharma Dive
