Crystalys Therapeutics Closes $130M Series B to Push Dotinurad Through Phase 3 Gout Trials

Crystalys Therapeutics announced on July 22, 2026 a $130 million Series B financing — oversubscribed and closed — less than a year after the company launched with a $205 million Series A announced September 30, 2025, according to the company's July 22, 2026 news release on PR Newswire.

Frazier Life Sciences led the Series B. New investors joining the round include Wellington Management, HBM Healthcare Investments, Soleus Capital, Cormorant Asset Management, Trails Edge Capital Partners, Pivotal bioVenture Partners, and KCap Biotechnology Fund. Existing backers — among them Novo Holdings, SR One, Catalys Pacific, Perceptive Xontogeny Venture Funds, Lightstone Ventures, AN Venture Partners, funds managed by abrdn Inc., KB Investments, Pontifax, Longwood Fund, Alexandria Venture Investments, Wedbush Healthcare Partners, and Prebys Ventures Fund — also participated, per the same release.

The single asset at the center of both rounds is dotinurad, a once-daily oral URAT1 inhibitor in clinical development as a second-line therapy to reduce uric acid, gout flares, and tophi. The compound was invented by Fuji Yakuhin and already holds regulatory approval in Japan, China, the Philippines, Taiwan, and Thailand. Crystalys acquired global ex-Asia rights via a 2024 asset purchase from Urica Therapeutics, a Fortress Biotech subsidiary that had originally licensed dotinurad from Fuji Yakuhin.

Proceeds from the Series B will fund three active clinical programs and commercial readiness activities. The RUBY trial compares dotinurad directly against allopurinol — the current standard first-line medication — in adults with hyperuricemia. The TOPAZ study targets patients with severe tophaceous gout. A Phase 2 study, AMETHYST, is also ongoing. The company says the runway extends through several expected clinical and regulatory milestones, per the July 22, 2026 PR Newswire announcement; that release did not disclose specific readout dates for RUBY or TOPAZ, nor did it describe the competitive significance of the head-to-head design relative to allopurinol.

"We are delighted to have the support of this strong syndicate of new investors and all our existing investors as we advance dotinurad through late-stage clinical development and into commercialization preparation," said James Mackay, Ph.D., President and Chief Executive Officer of Crystalys Therapeutics.

Crystalys is headquartered in San Diego and was co-founded by Catalys Pacific and Novo Holdings. Post-money valuation, share count, and warrant or pricing terms were not disclosed in the financing announcement. The company is private; no public-market price data applies.