UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G/A (Amendment No. 1) Under the Securities Exchange Act of 1934 Keryx Biopharmaceuticals, Inc. ------------------------------ Common Stock, no par value per share ------------------------------------ (Title of Class of Securities) 492515101 --------- CUSIP Number March 8, 2007 ------------- (Date of Event which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Schedule is filed: |_| Rule 13d-1(b) |X| Rule 13d-1(c) |_| Rule 13d-1(d) *The remainder of this cover page shall be filled out for a reporting person's initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page. The information required on the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes). Continued on following pages Page 1 of 5 Pages SCHEDULE 13G CUSIP No. 492505101 Page 2 of 5 1 Names of Reporting Persons I.R.S. Identification Nos. of above persons (entities only) LINDSAY A. ROSENWALD, M.D. 2 Check the Appropriate Box If a Member of a Group * a. |_| b. |_| 3 SEC Use Only 4 Citizenship or Place of Organization UNITED STATES 5 Sole Voting Power Number of 2,145,823 Shares Beneficially 6 Shared Voting Power Owned By 0 Each Reporting 7 Sole Dispositive Power Person 2,145,823 With 8 Shared Dispositive Power 0 9 Aggregate Amount Beneficially Owned by the Reporting Person 2,145,823 10 Check Box If the Aggregate Amount in Row (9) Excludes Certain Shares * |_| 11 Percent of Class Represented By Amount in Row (9) 4.9% 12 Type of Reporting Person * IN * see instructions before filling out CUSIP No. 492505101 Page 4 of 5 Item 1(a) Name of Issuer: Keryx Biopharmaceuticals Inc. (the "Issuer") Item 1(b) Address of the Issuer's Principal Executive Offices: 750 Lexington Avenue, 20th Floor New York, NY 10022 Item 2(a) Name of Person Filing: Lindsay A. Rosenwald, M.D. (the "Reporting Person"). Item 2(b) Address of Principal Business Office or, if None, Residence: c/o Paramount BioSciences, LLC 787 Seventh Avenue, 48th Floor New York, NY 10036 Item 2(c) Citizenship: United States. Item 2(d) Title of Class of Securities: Common Stock (the "Shares"). Item 2(e) CUSIP Number: 492505101 Item 3. If this statement is filed pursuant to Rule 13d-1(b), or 13d-2(b) or (c), check whether the person filing is a: This Item 3 is not applicable. Item 4. Ownership: Item 4(a) Amount Beneficially Owned: The Reporting Person beneficially owns 2,145,823 Shares, consisting of (i) 1,831,164 Shares held directly by the Reporting Person; (ii) warrants to purchase 14,064 Shares held directly by the Reporting Person; (iii) 250,485 Shares held by Paramount BioSciences, LLC, of which the Reporting Person is sole member; and (v) warrants to purchase 50,110 Shares held by Paramount BioSciences, LLC, of which the Reporting Person is sole member. Item 4(b) Percent of Class: See Item 11 of the cover page. Item 4(c) Number of shares as to which such person has: (i) Sole power to vote or direct the vote: Please see Item 5 of the cover page (ii) Shared power to vote or to direct the vote Please see Item 6 of the cover page (iii) Sole power to dispose or to direct the disposition of Please see Item 7 of the cover page (iv) Shared power to dispose or to direct the disposition of Please see Item 8 of the cover page Item 5. Ownership of Five Percent or Less of a Class: |X| This Schedule 13G/A is being filed voluntarily to indicate that due to an increase in the number of Shares currently outstanding, the Reporting Person is no longer subject to the reporting requirements of Schedule 13G with respect to his beneficial ownership of Shares, as he does not hold at least 5.0% of the Shares. Item 6. Ownership of More than Five Percent on Behalf of Another Person: See Item 4 Above Item 7. Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company: This Item 7 is not applicable. Item 8. Identification and Classification of Members of the Group: This Item 8 is not applicable. Item 9. Notice of Dissolution of Group: This Item 9 is not applicable. Item 10. Certification: By signing below each of the Reporting Persons certifies that, to the best of such person's knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the Issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having such purpose or effect. Page 5 of 5 SIGNATURES After reasonable inquiry and to the best of my knowledge and belief, the undersigned certifies that the information set forth in this statement is true, complete and correct. March 9, 2007 /s/ Lindsay A. Rosenwald, M.D. ------------------------------ Lindsay A. Rosenwald, M.D.