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                                                                    Exhibit 99.2


                         CERTIFICATION UNDER SECTION 302

I, Emile Loria, certify that:

1.      I have reviewed this 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-14 and 15d-14) for the registrant and have:

        a)     designed such disclosure controls and procedures 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)     evaluated the effectiveness of the registrant's disclosure
controls and procedures as of a date within 90 days prior to the filing date of
this report (the "Evaluation Date"); and

        c)     presented in this report our conclusions about the effectiveness
of the disclosure controls and procedures based on our evaluation as of the
Evaluation Date;

5.      The registrant's other certifying officers and I have disclosed, based
on our most recent evaluation, 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 in the design or operation of
internal controls which could adversely affect the registrant's ability to
record, process, summarize and report financial data and have identified for the
registrant's auditors any material weaknesses in internal controls; and

        b)     any fraud, whether or not material, that involves management or
other employees who have a significant role in the registrant's internal
controls; and

6.      The registrant's other certifying officers and I have indicated in this
report whether or not there were significant changes in internal controls or in
other factors that could significantly affect

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internal controls subsequent to the date of our most recent evaluation,
including any corrective actions with regard to significant deficiencies and
material weaknesses.

Date: October 21, 2002

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

I, Robert J. De Vaere, certify that:

1.      I have reviewed this 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-14 and 15d-14) for the registrant and have:

        a)     designed such disclosure controls and procedures 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)     evaluated the effectiveness of the registrant's disclosure
controls and procedures as of a date within 90 days prior to the filing date of
this report (the "Evaluation Date"); and

        c)     presented in this report our conclusions about the effectiveness
of the disclosure controls and procedures based on our evaluation as of the
Evaluation Date;

5.      The registrant's other certifying officers and I have disclosed, based
on our most recent evaluation, 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 in the design or operation of
internal controls which could adversely affect the registrant's ability to
record, process, summarize and report financial data and have identified for the
registrant's auditors any material weaknesses in internal controls; 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
controls; and

6.      The registrant's other certifying officers and I have indicated in this
report whether or not there were significant changes in internal controls or in
other factors that could significantly affect internal controls subsequent to
the date of our most recent evaluation, including any corrective actions with
regard to significant deficiencies and material weaknesses.

Date:   October 21, 2002
      ----------------------


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