The US Food and Drug Administration (FDA) has accepted Keryx Biopharmaceuticals' the filing of New Drug Application (NDA) for Zerenex (ferric citrate coordination complex). The acceptance for filing of the NDA indicates the determination by the FDA that the application is sufficiently complete to permit a substantive review.

Ron Bentsur, the Company's chief executive officer, said, "We are very pleased with the FDA's acceptance for filing of our NDA for Zerenex, as this represents an important achievement in the development of Zerenex. We believe that Zerenex has the potential to make a meaningful difference in the lives of patients with chronic kidney disease on dialysis, and we look forward to continuing to work with the FDA in its review process of the Zerenex NDA."

The Company's NDA, submitted on August 7, 2013, seeks approval for the marketing and sale of Zerenex as a treatment for elevated serum phosphorus levels, or hyperphosphatemia, in patients with chronic kidney disease (CKD) on dialysis.  Included in the NDA filing are safety and efficacy datasets derived from the Company's phase III registration program, which was conducted pursuant to a Special Protocol Assessment (SPA) agreement with the FDA, as well as safety and efficacy data from several additional studies, including four phase III studies conducted in Japan in CKD patients on dialysis.

Keryx holds a worldwide license (except for certain Asian Pacific countries) to Zerenex from Panion & BF Biotech, Inc. The Japanese rights are sublicensed by Keryx to Japan Tobacco Inc. (JT) and Torii Pharmaceutical Co., Ltd. (Torii). On January 7, 2013, JT announced the filing of its NDA with the Japanese Ministry of Health, Labour and Welfare for marketing approval of ferric citrate in Japan for the treatment of hyperphosphatemia in patients with CKD.

Zerenex is also in phase II development in the US for the management of elevated phosphorus and iron deficiency in anemic patients with Stage 3 to 5 non-dialysis dependent CKD.

The Special Protocol Assessment (SPA) process is a procedure by which the FDA provides official evaluation and written guidance on the design and size of proposed protocols that are intended to form the basis for a new drug application. Final marketing approval depends on the efficacy and safety results, including the adverse event profile, and an evaluation of the benefit/risk of treatment demonstrated in the phase III clinical programme. The SPA agreement may only be changed through a written agreement between the sponsor and the FDA, or if the FDA becomes aware of a substantial scientific issue essential to product efficacy or safety.

Keryx Biopharmaceuticals is focused on the acquisition, development and commercialization of medically important pharmaceutical products for the treatment of renal disease.