Arthrosi Snags $75M Series D

Arthrosi Therapeutics is strengthening its gout treatment program with the support of international investors.

The San Diego-based clinical-stage biotech company announced in mid-July it had secured a $75 million Series D funding round, led by Hong Kong investment group Guangrun  Health  Industry Co. Ltd. and backed by a consortium of investors that included Reichstein Biotech Co. Ltd, a subsidiary of China-based ApicHope Pharmaceuticals.

This latest funding round follows a joint venture Anthrosi launched in 2021 with Ruiao Biopharmaceutical Technology Co., Ltd. – another subsidiary of ApicHope – to form Guangzhou Ruianbo Pharmaceutical Technology Co., Ltd. to develop Anthrosi’s lead candidate AR822 for treatment of gout.

That registered joint venture was anticipated to result in a  $34.3 million  investment for development of its gout treatment in the greater  China  area, and another  $25 million  to participate in Arthrosi Therapeutics’ Series C equity financing.

Although Arthrosi has not always shared details of previous rounds, venture tracking website PitchBook estimates it to be as high as $154 million since the company launched in 2018.

Promising Clinical Data

Arthrosi’s Series D comes six months after the company announced promising clinical data for AR882 – a highly potent and selective next-gen urate transporter 1 (URAT1) inhibitor delivered in an oral capsule that has the potential to treat critical aspects of gout such as serum uric acid (sUA) levels, flares, and tophi reduction.

“I am not aware of any other molecule that has shown such promising results,” said Litain Yeh, Ph.D., co-founder and CEO of Arthrosi. “We continue to be extremely positive about how AR882 can address the significant unmet need in the gout space.”

In the U.S. alone, there are 9 million people who suffer from chronic gout and treatment options are limited. The potential market for AR882 is estimated to be more than $1 billion.

Yeh said the latest financing and continued partnership with ApicHope will accelerate the development of AR882 in the West and in Asia.

“We have been very impressed with the progress Arthrosi has demonstrated,” said Hanxiong Li, chairman and CEO of  ApicHope. The results of the Phase  2b  trials are exceptional and we expect the ongoing Phase 2 tophi trial to also show improvements in flares, sUA reduction, and tophi.”

Tophi, which is present in 20% of patients with gout, is the visible swelling at the joints which is caused by uric acid crystals forming masses of white growths around the joint tissues that look like swollen nodules.

Arthrosi’s Phase  2b  study was a global, multicenter, 12-week, randomized, double-blind, placebo-controlled study of 140 gout patients. The study found significant reductions in sUA levels in various levels of dosing that were not matched in the placebo group. Many of the patients in the study also had comorbidities such as diabetes, arthritis, liver disease and others.

“Current standards of care have been ineffective in addressing the underlying cause of gout and associated patient morbidity,” said Arthrosi Chief Medical Officer Robert T. Keenan, MD. “AR882 has not only demonstrated high response rates achieving the minimum sUA target of below 6 mg/dL needed to control the disease, but also demonstrated sufficient potency to achieve targets below 5 mg/dL or 4 mg/dL for faster flare reduction and dissolution of crystal deposition and tophi.”

In addition to the collaboration on AR822, Arthrosi and ApicHope are also pursuing precision medicine oncology with AR035, a therapeutic targeting non-small cell lung cancer.

Arthrosi Therapeutics, Inc.

Founded: 2018
CEO: Litain Yeh, Ph.D.
Headquarters: San Diego
Business: Biotech developing therapeutics in the gout and oncology spaces
Funding: Around $154 million; latest, $75 million Series D
Employees: 15
Website: arthrosi.com
Notable: Arthrosi was founded by a world-class team of gout experts who spearheaded the clinical development of the first generation of urate inhibitor treatment for gout at Ardea Biosciences resulting in a $1.26 billion acquisition by AstraZeneca.