NEW YORK, Dec. 4, 2014 (GLOBE NEWSWIRE) -- Keryx Biopharmaceuticals, Inc. (Nasdaq:KERX) announced today that the U.S. Patent and Trademark Office issued U.S. Patent No. 8,901,349 on December 2, 2014. The patent, which expires in 2024, claims a method of treating hyperphosphatemia comprising administering a therapeutically effective amount of an orally administrable form of ferric citrate to a subject, wherein the orally administrable form is prepared from a ferric citrate having a BET active surface area greater than about 16 sq. m/g. The patent also claims a broad category of orally administrable forms covering Auryxia, as well as other oral formulations that could be developed in the future.

On September 5, 2014, Auryxia™ (ferric citrate) was approved by the U.S. Food and Drug Administration for the control of serum phosphorus levels in patients with chronic kidney disease (CKD) on dialysis.

This newly issued patent further enhances the Company's key patent family, which includes U.S. Patent Nos. 7,767,851, 8,299,298, 8,338,642, 8,609,896, 8,754,257, 8,754,258, and 8,846,976 which expire in 2024, and U.S. Patent No. 8,093,423, which expires in 2026, before patent term extension. Each of these patents contains composition and method of use claims covering Auryxia.

Ron Bentsur, Chief Executive Officer of Keryx, commented, "The patent announced today represents our fourth U.S. patent issuance in 2014, and further fortifies the strength of our intellectual property position. This patent is significant in that it links orally administrable forms, including Auryxia, prepared from Keryx's unique API, having a surface area greater than about 16 sq. m/g." Mr. Bentsur added, "With the high surface area being a manufacturing specification for our API, we believe that the patent issued today provides another layer of substantial protection for Auryxia."

The Company continues to prosecute additional patent applications for Auryxia, which, if issued, would provide additional patent protection for Auryxia beyond 2030.  

In addition, the Company has filed its key patent families for Patent Term Extension, which, if granted, would add up to an additional 5 years to the patent protection for Auryxia. Following FDA approval, the FDA Substance Registration System adopted tetraferric tricitrate decahydrate as the name of the active ingredient approved for marketing by the FDA, to appropriately describe the Company's unique proprietary form of ferric citrate API. 

About Auryxia™ (ferric citrate)

Auryxia (ferric citrate) is an oral, absorbed, iron-based phosphate binder. In the United States, Auryxia was approved by the Food and Drug Administration (FDA) on September 5, 2014, for the control of serum phosphorus levels in patients with chronic kidney disease (CKD) on dialysis. Auryxia will be marketed in the U.S. by Keryx Biopharmaceuticals, Inc. Keryx plans to make Auryxia available to dialysis patients in the U.S. this year.

In January 2014, ferric citrate was approved for the treatment of patients with all stages of CKD in Japan, where it is being marketed as Riona® by Keryx's Japanese partner, Japan Tobacco Inc. and Torii Pharmaceutical Co. Ltd.

In March 2014, Keryx filed a Marketing Authorization Application (MAA) with the European Medicines Agency (EMA), seeking the approval of ferric citrate as a treatment of hyperphosphatemia in patients with CKD, including dialysis and non-dialysis dependent patients, and that application is currently under review.

For more information about Auryxia, visit www.Auryxia.com. For Full Prescribing Information for Auryxia, please visit http://keryx.com/wp-content/uploads/Auryxia_PI_Keryx_112014.pdf.

Auryxia (ferric citrate) Important Safety Information

Contraindication: Patients with iron overload syndrome, e.g. hemochromatosis, should not take Auryxia (ferric citrate).

Iron Overload: Iron absorption from Auryxia may lead to increased iron in storage sites. Iron parameters should be monitored prior to and while on Auryxia. Patients receiving IV iron may require a reduction in dose or discontinuation of IV iron therapy.

Accidental Overdose of Iron: Accidental overdose of iron containing products is a leading cause of fatal poisoning in children under 6 years of age. Keep Auryxia away from children as it contains iron. Call a poison control center or your physician in case of an accidental overdose in a child.

Patients with Gastrointestinal Bleeding or Inflammation: Safety has not been established for these patients.

Adverse Events: The most common adverse events with Auryxia were diarrhea (21%), nausea (11%), constipation (8%), vomiting (7%) and cough (6%)Gastrointestinal adverse reactions were the most common reason for discontinuing Auryxia (14%).

Auryxia contains iron and may cause dark stools, which is considered normal with oral medications containing iron.

Drug Interactions: Doxycycline should be taken at least 1 hour before Auryxia. 

For Full Prescribing Information for Auryxia, please visit http://keryx.com/wp-content/uploads/Auryxia_PI_Keryx_112014.pdf.

About Keryx Biopharmaceuticals, Inc.

Keryx Biopharmaceuticals, headquartered in New York, is focused on bringing innovative therapies to market for patients with renal disease. The Company's FDA-approved product, Auryxia, is indicated in the United States for the control of serum phosphorus levels in patients with chronic kidney disease on dialysis. Keryx plans to commercially launch Auryxia in the U.S. at year end. For more information regarding Keryx, please visit www.keryx.com

Cautionary Statement

Some of the statements included in this press release particularly those regarding Keryx's additional patent applications that may cover Auryxia™ (ferric citrate), the results of clinical trials or the commercialization and subsequent clinical development of Auryxia (ferric citrate), may be forward-looking statements that involve a number of risks and uncertainties. For those statements, we claim the protection of the safe harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995. Among the factors that could cause our actual results to differ materially include the fact that the U.S. Patent and Trademark Office, or other similar foreign patent authorities, may not issue those patents; whether Auryxia will be successfully launched and marketed in the U.S.; whether Riona® will be successfully marketed by our Japanese partner, Japan Tobacco, Inc. and Torii Pharmaceutical Co., Ltd; the risk that the EMA may not concur with our interpretation of our Phase 3 study results, supportive data, conduct of the studies, or any other part of our MAA submission and could ultimately deny approval of the MAA; the risk that we may not be successful in the development of ferric citrate for the treatment of iron deficiency anemia in non-dialysis chronic kidney disease patients; and other risk factors identified from time to time in our reports filed with the Securities and Exchange Commission. Any forward-looking statements set forth in this press release speak only as of the date of this press release. We do not undertake to update any of these forward-looking statements to reflect events or circumstances that occur after the date hereof. This press release and prior releases are available at http://www.keryx.com. The information found on our website is not incorporated by reference into this press release and is included for reference purposes only.

CONTACT: Amy Sullivan, Vice President - Corporate Development and Public Affairs
         Keryx Biopharmaceuticals, Inc.
         Tel: 617.466.3447; e-mail: amy.sullivan@keryx.com

Keryx Logo