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                                                                   EXHIBIT 10.37

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       AMENDMENT NO. 5 TO AMENDED AND RESTATED RECAPITALIZATION AGREEMENT

      THIS AMENDMENT NO. 5 TO AMENDED AND RESTATED RECAPITALIZATION AGREEMENT
(this "AMENDMENT") is made and entered into as of April 12, 2005 (the "FIFTH
AMENDMENT DATE") by and between NORTHWEST BIOTHERAPEUTICS, INC., and its
affiliates, if any (collectively, the "COMPANY"), a Delaware corporation with
offices at 22322 20th Ave SE, Suite 150, Bothell, Washington, 98021, and TOUCAN
CAPITAL FUND II, L.P., and its designees (collectively, "INVESTOR"), a Delaware
limited partnership with offices at 7600 Wisconsin Avenue, Bethesda, MD 20814.
All capitalized terms used herein but not otherwise defined shall have the
meaning given such terms in the Agreement (as defined below).

                                    RECITALS

      WHEREAS, the Company and Investor have entered into that certain Amended
and Restated Recapitalization Agreement, dated as of July 30, 2004 (the
"AGREEMENT");

      WHEREAS, on October 22, 2004, the Company and Investor entered into
Amendment No. 1 to the Agreement;

      WHEREAS, on November 10, 2004, the Company and Investor entered into
Amendment No. 2 to the Agreement;

      WHEREAS, on December 27, 2004, the Company and Investor entered into
Amendment No. 3 to the Agreement;

      WHEREAS, on January 26, 2005, the Company and Investor entered into
Amendment No. 4 to the Agreement;

      WHEREAS, the Company and Investor desire to further amend the Agreement to
make such changes to the Agreement as are set forth herein; and

      WHEREAS, Section 4.13(f) of the Agreement provides that the Agreement may
be amended or modified only by a written instrument signed by the Company and
Investor.

                                    AMENDMENT

      NOW, THEREFORE, for and in consideration of the mutual promises and
covenants set forth herein and for other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the Company and
Investor hereby agree as follows:

1. Section 1.2 of the Agreement is hereby amended by inserting "and the Loan
Agreement, Security Agreement and 10% Convertible, Secured Promissory Note dated
April 12, 2005 attached hereto as Exhibit A-9, and the April 12 Bridge Warrant
(as defined herein) in the form attached hereto as Exhibit K-4" immediately
following the phrase "in the form attached hereto as Exhibit K-3" in subsection
(g) thereof.

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2.    Section 2.2(a) of the Agreement is hereby amended by replacing "A-8" with
"A-9."

3.    Section 2.3(b) of the Agreement is hereby amended by adding the following
text immediately following the twelfth sentence thereof:

      "On April 12, 2005 (the "FIFTH AMENDMENT DATE"), Investor is providing an
      additional $450,000 of Bridge Funding (the "APRIL 12 BRIDGE FUNDING") to
      cover general operating expenses and certain other expenses of the Company
      agreed in advance by Investor during the period from March 25, 2005
      through April 30, 2005. The April 12 Bridge Funding shall be evidenced by
      a Note in the form attached hereto as Exhibit A-9 and shall be provided on
      the terms and conditions set forth herein. The April 12 Bridge Funding
      shall be used only for the purposes and in the amounts agreed to in
      writing by Investor and the Company."

4.    Section 2.3(b) of the Agreement is hereby further amended by replacing the
phrase "or December 27 Bridge Funding" with "December 27 Bridge Funding or April
12 Bridge Funding" in the thirteenth sentence thereof (i.e., the sixteenth
sentence thereof after giving effect to the inclusion of the three new sentences
therein per Section 3 of this Amendment).

5.    The Agreement is hereby amended by adding a new Section 2.14, immediately
following Section 2.13 thereof, as follows:

      "2.14 April 12 Bridge Warrant:

            (a) Issuance of April 12 Bridge Warrant. On the Fifth Amendment
      Date, Investor shall receive a warrant with coverage equal to one hundred
      percent (100%) of the principal amount due under the Note evidencing the
      April 12 Bridge Funding (the "APRIL 12 BRIDGE WARRANT"). The Company
      shall, therefore, issue $450,000 in warrant coverage on the $450,000 of
      April 12 Bridge Funding provided on the Fifth Amendment Date. The number
      of shares subject to the April 12 Bridge Warrant to be so issued shall be
      determined on the basis of $0.10 per share (subject to adjustment for
      stock splits, stock dividends and the like). The total number of shares
      for which Investor shall initially be able to exercise the April 12 Bridge
      Warrant shall therefore be 4,500,000 shares as of the Fifth Amendment
      Date.

            (b) Exercise of April 12 Bridge Warrant. The April 12 Bridge Warrant
      shall be immediately exercisable upon issuance and continue to be
      exercisable for a period of seven (7) years after its issuance date. The
      exercise price of the April 12 Bridge Warrant shall be $0.04 (subject to
      adjustment for stock splits, stock dividends and the like, as provided
      more fully in the April 12 Bridge Warrant). In the event the Convertible
      Preferred Stock is approved and authorized, and the terms and conditions
      are the same as set forth herein and in the Convertible Preferred Stock
      Term Sheet, and Other Investors have purchased in cash (and not by
      conversion of debt, exercise of warrants or options, or conversion or
      exercise of other securities or instruments) a minimum of $15 million of
      such Convertible Preferred Stock, on the terms and conditions set forth
      herein and in the Convertible Preferred Stock Term Sheet, then the April
      12 Bridge Warrant shall be exercisable solely for such Convertible
      Preferred Stock (subject to Section 5 thereof). However, if, for any
      reason, such Convertible

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      Preferred Stock is not approved or authorized, and/or is approved or
      authorized on any terms different than any terms set forth herein and in
      the Convertible Preferred Stock Term Sheet, and/or if Other Investors have
      not purchased in cash (and not by conversion of debt, exercise of warrants
      or options, or conversion or exercise of other securities or instruments)
      a minimum of $15 million of such Convertible Preferred Stock, on the terms
      and conditions set forth herein and in the Convertible Preferred Stock
      Term Sheet, the April 12 Bridge Warrant shall be exercisable for any
      Equity Security and/or Debt Security (each as defined in Section 2.7
      hereof) and/or any combination thereof, in each case that Investor shall
      designate in Investor's sole discretion (the securities so elected being
      the "INVESTOR DESIGNATED SECURITIES").

            (c) No Impairment. The Company shall not, by amendment of its
      Charter or through a reorganization, transfer of assets, consolidation,
      merger, dissolution, issue or sale of securities, or any other voluntary
      action, omission, or agreement, avoid or seek to avoid the observance or
      performance of any of the terms to be observed or performed by the Company
      under and/or in connection with the April 12 Bridge Warrant, but shall at
      all times in good faith use best efforts to assist in carrying out of all
      the provisions of and/or relating to such April 12 Bridge Warrant and in
      taking all such action as may be necessary or appropriate to protect
      Investor's rights, preferences and privileges under and/or in connection
      with the April 12 Bridge Warrant against impairment. Investor's rights,
      preferences and privileges granted under and/or in connection with the
      April 12 Bridge Warrant may not be amended, modified or waived without
      Investor's prior written consent, and the documentation providing for such
      rights, preferences and privileges will specifically provide as such.

            (d) Tax Treatment of April 12 Bridge Warrant and Note. The Company
      and Investor, as a result of arm's length bargaining, agree that the fair
      market value of the Note to be issued in connection with the April 12
      Bridge Funding, if issued apart from the April 12 Bridge Warrant, is
      $445,500, and the fair market value of the April 12 Bridge Warrant, if
      issued apart from such Note, is $4,500. The Company and Investor further
      agree that all tax filings and records relating to or including this
      Agreement, the Note to be issued in connection with the April 12 Bridge
      Funding and/or the April 12 Bridge Warrant shall be prepared on the basis
      of, and consistently reflect, the agreed fair market values set forth in
      this Section 2.14(d), and the Company shall instruct its accountants and
      other tax-preparation professionals to prepare all tax filings and returns
      on the basis of the foregoing."

6.    Section 3.4(b) of the Agreement is hereby amended by:

      (a)   replacing "$6.75 million" with "$6.3 million" in the first sentence
            thereof; and

      (b)   replacing " "67,500,000" with "63,000,000" in the third sentence
            thereof.

7.    Section 4.7.6 of the Agreement is hereby amended and restated in its
entirety as follows:

            "4.7.6. Capitalization. The authorized capital stock of the Company
      consists of 300,000,000 shares of Common Stock, par value $0.001 per share
      and 100,000,000

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      shares of Preferred Stock, par value of $0.001 per share. As of the date
      hereof, 19,028,779 shares of Common Stock and 32,500,000 shares of series
      A preferred stock are issued and outstanding. No other shares of any class
      or series of the Company's capital stock are authorized and/or issued and
      outstanding. All issued and outstanding shares of capital stock of the
      Company have been duly authorized and validly issued, and are fully paid
      and non-assessable, and have been offered, sold and delivered by the
      Company in compliance with all applicable federal and state securities
      laws. Except as set forth in Schedule 4.7.6, no subscription, warrant,
      option, convertible security, or other right (direct or indirect,
      contingent or otherwise) to purchase or otherwise acquire any equity
      securities of the Company is authorized or outstanding, and there is no
      agreement, promise, commitment, undertaking or letter of intent of any
      kind (direct or indirect, contingent or otherwise) by the Company to issue
      any shares, subscriptions, warrants, options, convertible securities, or
      other such rights, or to distribute to holders of any of its equity
      securities any evidence of indebtedness or asset. Except as set forth in
      Schedule 4.7.6, the Company has no obligation of any kind (direct or
      indirect, contingent or otherwise) to purchase, redeem or otherwise
      acquire any of its equity securities or any interest therein or to pay any
      dividend or make any other distribution in respect thereof. Schedule 4.7.6
      includes a true, accurate and complete statement describing the total
      number of shares of the Company outstanding as of the date of this
      Agreement (on a fully diluted basis, including, without limitation, all
      warrants and options outstanding (whether or not currently exercisable),
      all convertible instruments of any kind (whether or not currently
      convertible), shares of all classes of stock, and any agreements,
      promises, commitments, undertakings or letters of intent to issue any of
      the foregoing."

8.    Section 4.7.15 of the Agreement is hereby amended and restated in its
entirety as follows:

            "4.7.15 Liabilities. The Company has the following accrued
      liabilities: (i) tax liabilities to the State of Washington in the maximum
      amount of $494,000, (ii) amounts payable to Cognate Therapeutics and (iii)
      future sublease payments to MediQuest Corporation for the Company's
      premises sublease not yet due, and a contingent lease liability to
      Benaroya Capital Co. LLC for premises currently occupied by MediQuest
      Corporation should Mediquest Corporation default on its lease with
      Benaroya Capital Co. LLC and which is not yet due, (iv) the Company's
      aggregate accrued, contingent and/or other liabilities of any nature,
      either mature or immature, as of the Fifth Amendment Date, do not exceed
      $350,525 (excluding amounts payable to Cognate), of which (x) $231,356 are
      currently due payables (including $204,812 for attorney and auditor fees),
      (y) $43,505 are the aggregate balances of capital leases payable in
      monthly installments in the amounts set forth in the budget included in
      the Schedule of Exceptions through the first calendar quarter of 2006,
      decreasing thereafter, the last of which is fully amortized in May 2007,
      and (z) $75,664 are accrued vacation and sick pay."

9.    The Agreement is hereby amended by adding new Exhibit A-9, immediately
following Exhibit A-8 thereto, in the form attached as Exhibit A-9 hereto.

10.   Exhibit B to the Agreement, as amended on December 27, 2004 and January
26, 2005, is hereby further amended by Exhibit B-3 hereto (the "THIRD AMENDMENT
TO THE AMENDED AND RESTATED CONVERTIBLE PREFERRED STOCK TERM SHEET"). Exhibit B,
as so amended, shall be deemed to constitute

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the "CONVERTIBLE PREFERRED STOCK TERM SHEET" for all purposes under the
Agreement and all other Related Recapitalization Documents.

11.   The Agreement is hereby amended by adding new Exhibit K-4, immediately
following Exhibit K-3 thereto, in the form attached as Exhibit K-4 hereto.

12.   The April 12 Bridge Warrant in the form attached hereto as Exhibit K-4
shall be deemed to be a "BRIDGE WARRANT" and a "WARRANT" for all purposes under
the Agreement and any Related Recapitalization Document. The Note evidencing the
April 12 Bridge Funding in the form attached hereto as Exhibit A-9 issued on the
Fifth Amendment Date shall be deemed to be a "NOTE" for all purposes under the
Agreement and any Related Recapitalization Document. Each of the April 12 Bridge
Warrant and the Note evidencing the April 12 Bridge Funding shall be deemed to
be "RELATED RECAPITALIZATION DOCUMENTS" for all purposes under the Agreement and
all other Related Recapitalization Documents.

13.   Except as amended and/or restated hereby, all other terms and conditions
of the Agreement shall be unaffected hereby and remain in full force and effect.

14.   This Amendment (including the Exhibits hereto, which are an integral part
of the Amendment), together with the Agreement (including the Schedules and
Exhibits thereto, which are an integral part of the Agreement) and the Related
Recapitalization Documents, constitute the entire agreement among the parties
hereto and thereto with regard to the subjects hereof and thereof and supersede
all prior agreements and understandings relating to the subject matter hereof
and thereof.

15.   This Amendment shall be governed by and construed under the laws of the
State of Delaware, without regard to its conflicts of law provisions.

16.   This Amendment may be executed in one or more counterparts, each of which
will be deemed an original but all of which together shall constitute one and
the same agreement.

17.   This Amendment shall take effect immediately upon execution by the Company
and Investor.

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      IN WITNESS WHEREOF, the parties hereto have executed this AMENDMENT NO. 5
TO AMENDED AND RESTATED RECAPITALIZATION AGREEMENT as of the Fifth Amendment
Date above written.

                                     NORTHWEST BIOTHERAPEUTICS, INC.

                                     By: /s/ Alton L. Boynton
                                     Name: Alton L. Boynton
                                     Title: President

                                     TOUCAN CAPITAL FUND II, LP

                                     By: /s/ Linda F. Powers
                                     Name: Linda F. Powers
                                     Title: Managing Director

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                                   EXHIBIT A-9

    FORM OF $450,000 LOAN AGREEMENT, SECURITY AGREEMENT AND 10% CONVERTIBLE,
                  SECURED PROMISSORY NOTE DATED APRIL 12, 2005

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                                   EXHIBIT B-3

      FORM OF THIRD AMENDMENT TO AMENDED AND RESTATED CONVERTIBLE PREFERRED
                                STOCK TERM SHEET

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                                   EXHIBIT K-4
                         FORM OF APRIL 12 BRIDGE WARRANT

                                       9.