OPKO Health Inc. (NASDAQ: OPK) announced its subsidiary EirGen Pharma Limited amended an agreement with Nicoya Therapeutics (Macau) Limited, granting OPKO a 15% equity stake in Nicoya in exchange for revised royalty and transfer price terms for RAYALDEE commercialization in Greater China.

The amended agreement expands the original June 2021 deal for developing and commercializing RAYALDEE, a treatment for secondary hyperparathyroidism in patients with stage 3 or 4 chronic kidney disease. RAYALDEE has received approval in Macau, with regulatory approvals expected in China and related territories in 2027.

Under the revised terms, OPKO received Series A-2 Preferred Shares in Nicoya, set to close in two tranches. The milestone structure remains unchanged, with OPKO eligible to receive up to $115 million upon achievement of development, regulatory and sales-based milestones.

"China is a major growth opportunity with over 20 million adults affected by stage 3 or 4 chronic kidney disease," said Phillip Frost, Chairman and Chief Executive Officer of OPKO.

RAYALDEE is an extended-release formulation of calcifediol approved by the U.S. Food and Drug Administration to treat secondary hyperparathyroidism in adults with stage 3 or 4 chronic kidney disease and vitamin D insufficiency. The product launched in the U.S. in November 2016.

Nicoya Therapeutics is a renal-focused biotechnology company incubated by 6 Dimensions Capital and its successor fund 120 Capital, focusing on the China nephrology market.