EXHIBIT 12.1
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               CERTIFICATION REQUIRED BY RULE 13A-14(A) OR 15D-14
                     OF THE SECURITIES EXCHANGE ACT OF 1934

CERTIFICATION

I, Terrance H. Gregg, certify that:

1.     I have reviewed this Amendment No. 1 to the annual report on Form 20-F/A
       of Vasogen;

2.     Based on my knowledge, this report does not contain any untrue statement
       of a material  fact or omit to state a material  fact  necessary to make
       the  statements  made,  in light of the  circumstances  under which such
       statements  were made, not misleading with respect to the period covered
       by this report;

3.     Based on my knowledge,  the financial  statements,  and other  financial
       information  included in this  report,  fairly  present in all  material
       respects the financial  condition,  results of operations and cash flows
       of the issuer as of, and for, the periods presented in this report;

4.     The  issuer's  other  certifying  officers  and  I are  responsible  for
       establishing  and  maintaining  disclosure  controls and  procedures (as
       defined in Exchange Act Rules  13a-15(e) and  15d-15(e))  for the issuer
       and have:

       a)     Designed such disclosure controls and procedures,  or caused such
              disclosure  controls  and  procedures  to be  designed  under our
              supervision,  to ensure that material information relating to the
              issuer, including its consolidated subsidiaries, is made known to
              us by others  within  those  entities,  particularly  during  the
              period in which this report is being prepared;

       b)     Evaluated the effectiveness of the issuer's  disclosure  controls
              and procedures and presented in this report our conclusions about
              the effectiveness of the disclosure  controls and procedures,  as
              of the end of the  period  covered by this  report  based on such
              evaluation; and

       c)     Disclosed  in this  report  any change in the  issuer's  internal
              control over financial  reporting that occurred during the period
              covered by the annual report that has materially affected,  or is
              reasonably  likely to materially  affect,  the issuer's  internal
              control over financial reporting; and

5.     The issuer's other  certifying  officers and I have disclosed,  based on
       our most recent evaluation of internal control over financial reporting,
       to the issuer's  auditors and the audit  committee of the issuer's board
       of directors (or persons performing the equivalent functions):

       a)     All  significant  deficiencies  and  material  weaknesses  in the
              design or operation of internal control over financial  reporting
              which are  reasonably  likely to  adversely  affect the  issuer's
              ability  to  record,  process,  summarize  and  report  financial
              information; and

       b)     Any fraud,  whether or not material,  that involves management or
              other  employees  who  have a  significant  role in the  issuer's
              internal control over financial reporting.


/s/ TERRANCE H. GREGG
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Terrance H. Gregg
President and Chief Executive Officer (Principal Executive Officer),
Vasogen Inc.

May 17, 2007