By Sriparna Roy

Sept 30 (Reuters) - Crystalys Therapeutics said on Tuesday it has emerged from stealth mode with a funding round of $205 million to help finance global late-stage trials of its lead drug as a treatment for gout.

The Series A financing round was co-led by Novo Holdings, the controlling shareholder of obesity drugmaker Novo Nordisk NOVOb.CO, SR One and Catalys Pacific, and had participation from other investors.

The company, which had a pre-money valuation of $75 million, had closed an initial investment in June, and had been working with three to four additional investors for a second capital raise, CEO James Mackay told Reuters.

Crystalys is accelerating two late-stage trials of dotinurad, a once-daily oral drug being evaluated in the U.S. and Europe as a second-line treatment for gout in patients unresponsive to first-line therapies.

"There really is no available second-line treatment for these patients," said Mackay adding that while Amgen's AMGN.O intravenous drug Krystexxa is successful as a third-line treatment, the high price limits it to a small portion of patients.

Gout is a type of inflammatory arthritis, which is caused by buildup of uric acid in the body and leads to pain and swelling in the joints.

Dotinurad belongs to a class of drugs which block the urate transporter 1 (URAT1) in the kidneys, helping increase the excretion of uric acid and lowering the blood levels of the substance.

"Normally, you have to conduct replicate clinical trials, but because of the extensive data that existed, the FDA agreed that we could do two clinical trials, but two different designs," Mackay said.

One trial is focused on reducing gout flares, while the other aims to resolve tophi which are large uric acid crystal deposits.

The San Diego-based company gained access to the drug from Urica Therapeutics, a unit of Fortress Biotech FBIO.O which originally licensed the drug from Japan-based Fuji Yakuhin.

Fuji Yakuhin out-licensed the drug in China and other Asian countries to Eisai 4523.T. It is approved in China under the brand name Urece.

(Reporting by Sriparna Roy in Bengaluru; Editing by Krishna Chandra Eluri)

((Sriparna.Roy@thomsonreuters.com;))