EXHIBIT 99.1

                CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350,
                             AS ADOPTED PURSUANT TO
                  SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the annual report on Form 10-K of Keryx Biopharmaceuticals,
Inc. (the "Company") for the period ended December 31, 2003, as filed with the
Securities and Exchange Commission on the date hereof (the "Report"), the
undersigned, Michael S. Weiss, Chief Executive Officer of the Company, hereby
certifies, pursuant to 18 U.S.C. Section 1350, that:

(a) the Report fully complies with the requirements of Section 13(a) or 15(d) of
the Securities Exchange Act of 1934; and

(b) the information contained in the Report fairly presents, in all material
respects, the financial condition and results of operations of the Company.


                                         /s/ Michael S. Weiss
                                         --------------------------------------
Dated: March 31, 2003                    Michael S. Weiss
                                         Chief Executive Officer
                                         (Principal Executive Officer)

                CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350,
                             AS ADOPTED PURSUANT TO
                  SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the annual report on Form 10-K of Keryx Biopharmaceuticals,
Inc. (the "Company") for the period ended December 31, 2003, as filed with the
Securities and Exchange Commission on the date hereof (the "Report"), the
undersigned, Ira Weinstein, Interim Chief Financial Officer of the Company,
hereby certifies, pursuant to 18 U.S.C. Section 1350, that:

(a) the Report fully complies with the requirements of Section 13(a) or 15(d) of
the Securities Exchange Act of 1934; and

(c) the information contained in the Report fairly presents, in all material
respects, the financial condition and results of operations of the Company.


                                         /s/ Ira Weinstein
                                         --------------------------------------
Dated: March 31, 2003                    Ira Weinstein
                                         Interim Chief Financial Officer
                                         (Principal Financial and Accounting
                                         Officer)