Fenwick & West LLP represented Ultragenyx Pharmaceutical Inc., a clinical-stage biotechnology company committed to bringing to market life-transforming therapeutics for patients with rare and ultra-rare metabolic genetic diseases, in a collaboration and license agreement with Kyowa Hakko Kirin Co., Ltd. to develop and commercialize KRN23, a recombinant fully human monoclonal IgG1 antibody intended to treat X-linked hypophosphatemia (XLH). Under the terms of the agreement, Kyowa Hakko Kirin and Ultragenyx will collaborate on the development of KRN23 for the US, Canada and European Union, with Ultragenyx leading development efforts in the XLH indication and the parties sharing development costs. In the US and Canada, Kyowa Hakko Kirin and Ultragenyx will share commercial responsibilities and profits. Kyowa Hakko Kirin will commercialize KRN23 in the EU. Ultragenyx will develop and commercialize the product in Mexico, Central and South America.
XLH is a rare metabolic bone disorder caused by excessive loss of phosphate in the urine, and XLH patients have low serum phosphate levels due to high levels of FGF23, a hormone that represses the reabsorption of phosphate from the urine. KRN23 is intended to bind to and render FGF23 inactive, leading to an increase in kidney tubular absorption of phosphate and increased serum phosphate levels. KRN23 was found and is developed by Kyowa Hakko Kirin as the only product targeting FGF23 in the world.
The Fenwick transaction team was led by partner Effie Toshav and included associates Stefano Quintini and Ranjit Narayanan.
More information can be found on Ultragenyx’s website.