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                                   Exhibit 31

                         CERTIFICATION UNDER SECTION 302

I, Emile Loria, certify that:

1.       I have reviewed this quarterly report on Form 10-Q of Epimmune Inc.;

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 registrant as
of, and for, the periods presented in this report;

4.       The registrant's other certifying officer(s) 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 registrant and we have:

         a)       Designed such disclosure controls and procedures, or cause
such disclosure controls and procedures to be designed under our supervision, to
ensure that material information relating to the registrant, 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)       Designed such internal control over financial reporting, or
caused such internal control over financial reporting to be designed under our
supervision, to provide reasonable assurance regarding the reliability of
financial reporting and the preparation of financial statements for external
purposes in accordance with generally accepted accounting principles;

         c)       Evaluated the effectiveness of the registrant'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

         d)       Disclosed in this report any change in the registrant's
internal control over financial reporting that occurred during the registrant's
most recent fiscal quarter that has materially affected, or is reasonably likely
to materially affect, the registrant's internal control over financial
reporting; and

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

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         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 registrant'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 registrant's internal
control over financial reporting.

Date: November 10, 2003

                                          /s/ Emile Loria
                                          --------------------------------------
                                          Dr. Emile Loria
                                          President and Chief Executive Officer

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I, Robert J. De Vaere, certify that:

1.       I have reviewed this quarterly report on Form 10-Q of Epimmune Inc.;

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 registrant as
of, and for, the periods presented in this report;

4.       The registrant'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 registrant and we have:

         a)       Designed such disclosure controls and procedures, or cause
such disclosure controls and procedures to be designed under our supervision, to
ensure that material information relating to the registrant, 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)       Designed such internal control over financial reporting, or
caused such internal control over financial reporting to be designed under our
supervision, to provide reasonable assurance regarding the reliability of
financial reporting and the preparation of financial statements for external
purposes in accordance with generally accepted accounting principles;

         c)       Evaluated the effectiveness of the registrant'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

         d)       Disclosed in this report any change in the registrant's
internal control over financial reporting that occurred during the registrant's
most recent fiscal quarter that has materially affected, or is reasonably likely
to materially affect, the registrant's internal control over financial
reporting; and

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

         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 registrant's ability to record,
process, summarize and report financial information; and

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

Date: November 10, 2003

                                                  /s/ Robert J. De Vaere
                                                  ------------------------------
                                                  Robert J. De Vaere
                                                  Vice President, Finance and
                                                  Administration, and Chief
                                                  Financial Officer

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