X0306 4/A 2016-08-09 2016-08-11 0 0001114220 KERYX BIOPHARMACEUTICALS INC KERX 0001564955 Madison Greg C/O KERYX BIOPHARMACEUTICALS, INC. ONE MARINA PARK DRIVE, 12TH FLOOR BOSTON MA 02210 1 1 0 0 President and CEO Common Stock 257123 D On August 11, 2016, two Forms 4 were inadvertently filed reporting the same automatic sale of a total of 1,622 shares of common stock in order to satisfy Mr. Madison's income tax withholding obligation upon the vesting of 5,000 shares of restricted stock on August 8, 2016. This filing amends the second Form 4 filed on August 11, 2016 to remove the duplicative reporting of such sale of common stock. As of August 9, 2016 and includes 180,687 shares of restricted stock. /s/ Brian Adams, Attorney-in-Fact 2016-09-01