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                                                               EXECUTION VERSION


EXHIBIT 10.3


                               FIRST AMENDMENT TO
                       WARRANTS TO PURCHASE COMMON SHARES

      THIS FIRST AMENDMENT TO WARRANTS TO PURCHASE COMMON SHARES (the
"AMENDMENT") is made and entered into as of April 25, 2004, by and among
NORTHWEST BIOTHERAPEUTICS, INC., a Delaware corporation (the "COMPANY"), and the
undersigned holders of Warrants (as defined below) to acquire shares of the
Company's common stock (each a "WARRANTHOLDER" and, collectively, the
"WARRANTHOLDERS"). When signed by the holders of at least 50% of the common
stock subject to Warrants (as defined below) this Amendment will amend each of
the Warrants .

                                    RECITALS

      WHEREAS, the Company and the undersigned Warrantholder(s) desire to amend
all of the Company Warrants to Purchase Common Shares, of series Nos. BR-1
through BR-5, each dated as of November 13, 2003 (each, a "WARRANT" and,
collectively, the "WARRANTS"), as provided herein.

                                    AGREEMENT

      NOW, THEREFORE, in consideration of the mutual covenants and promises
contained herein, and for other good and valuable consideration, the receipt and
adequacy of which are hereby acknowledged, the parties agree as follows:

1.    Section 8(a) of each Warrant is hereby amended and restated in its
      entirety as follows:

            "(a) In the event of changes in the Common Stock by reason of stock
      dividends, splits, recapitalizations, reclassifications, combinations or
      exchanges of shares, separations, reorganizations, liquidations, or the
      like, the number and class of Warrant Shares available under this Warrant
      in the aggregate and the Warrant Price shall be correspondingly adjusted
      to give the Warrantholder, on exercise for the same Aggregate Warrant
      Price, the total number, class, and kind of shares as the Warrantholder
      would have owned had this Warrant been exercised prior to the event and
      had the Warrantolder continued to hold such shares until after the event
      requiring adjustment. Notwithstanding the foregoing, no adjustment to the
      number of Warrant Shares or the Warrant Price shall be made in the event
      of an issuance or deemed issuance of securities for consideration below
      the then current Warrant Price pursuant to this Section 8(a). For purposes
      of this Section 8(a), the "AGGREGATE WARRANT PRICE" shall mean the
      aggregate Warrant Price payable in connection with the exercise in full of
      this Warrant. The form of this Warrant need not be changed because of any
      adjustment in the number of Warrant Shares subject to this Warrant."

2.    The first paragraph of Section 8(d) of each Warrant is hereby amended and
      restated in its entirety to read as follows:

            "Except as provided in subsections (e) and (f) of this Section 8, if
      and whenever the Company shall issue or sell, or is, in accordance with
      any of subsections (d)(l) through (d)(6) hereof, deemed to have issued or
      sold, any shares of Common Stock for no consideration or for a
      consideration per share less than the Warrant Price in effect immediately
      prior to the time of such issue or sale, then and in each such case (a
      "Trigger Issuance") the then-existing Warrant Price, shall be reduced, as
      of the close of business on the effective date of the Trigger Issuance, to
      the lowest price per share at which any share of Common Stock was issued
      or sold or deemed to be issued or sold, but in no event shall the Warrant
      Price be reduced to less than the lesser of $0.10 per share (subject to
      adjustment as provided in Section 8(a)) or 35% discount to the average
      closing price during the twenty trading days prior to the first closing of
      the sale by the Company of Convertible Preferred Stock, par value $0.001
      per share as contemplated by that certain Recapitalization Agreement dated
      as of April 26, 2004 between the Company and Toucan Capital Fund II, L.P.;
      provided, however, that in no event will the Warrant Price be less than
      $.04 per share (subject to adjustment as provided in Section 8(a))"

3.    Section 8(f) of each Warrant is hereby amended and restated in its
      entirety to read as follows:

            "Anything to the contrary herein notwithstanding, in no event shall
      the then existing Warrant Price be reduced to less than the lesser of
      $0.10 per share (subject to adjustment as provided in Section 8(a)) or 35%
      discount to the average closing price during the twenty trading days prior
      to the first closing of the sale by the Company of Convertible Preferred
      Stock, par value $0.001 per share as contemplated by that certain
      Recapitalization Agreement dated as of April 26, 2004 between the Company
      and Toucan Capital Fund II, L.P.; provided, however, that in no event will
      the Warrant Price be less than $.04 per share (subject to adjustment as
      provided in Section 8(a)) pursuant to the adjustments provided for in
      Section 8(d)."
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                                                               EXECUTION VERSION

4.    Sections 8(b) and 8(c) of each Warrant are hereby deleted in their
      entirety.

5.    Section 18 of each Warrant is hereby deleted in its entirety.

6.    All other terms and conditions of the Warrants shall be unaffected hereby
      and remain in full force and effect.

7.    This Amendment shall be governed by and construed under the laws of the
      State of Washington as applied to agreements among Washington residents
      entered into and to be performed entirely within the State of Washington.

8.    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.

                            [SIGNATURE PAGE FOLLOWS]

                                       2.
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                                                               EXECUTION VERSION


      IN WITNESS WHEREOF, the parties hereto have executed this FIRST AMENDMENT
TO WARRANT TO PURCHASE COMMON SHARES as of the date first above written.

                                 COMPANY:

                                 NORTHWEST BIOTHERAPEUTICS, INC.,
                                 a Delaware corporation

                                 By:
                                    ----------------------------------------
                                 Name:
                                 Title:

                                 WARRANTHOLDERS:

                                 /s/ Alton L. Boynton
                                 --------------------------------------------
                                 Alton L. Boynton

                                 /s/ Marnix L. Bosch
                                 --------------------------------------------
                                 Marnix L. Bosch

                                 /s/ Eric H. Holmes
                                 --------------------------------------------
                                 Eric H. Holmes

                                 /S/ Larry L. Richards
                                 --------------------------------------------
                                 Larry Richards




              FIRST AMENDMENT TO WARRANT TO PURCHASE COMMON SHARES