<PAGE>
                                                                    EXHIBIT 31.2

                            SECTION 302 CERTIFICATION

I Larry L. Richards, certify that:

(1)   I have reviewed this quarterly report on Form 10-Q of Northwest
      Biotherapeutics, 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
      quarterly report;

(3)   Based on my knowledge, the financial statements, and other financial
      information included in this quarterly 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
      quarterly 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
            quarterly 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 quarterly report (the "Evaluation Date"); and

      c.    Presented in this quarterly 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 the 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
      quarterly report whether or not there were significant changes in internal
      controls or in other factors that could significantly


<PAGE>

      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:    August 13, 2003

      By:      /s/ Larry L. Richards
               Larry L. Richards
               Controller (Principal Financial and Accounting Officer)