FIFTH AMENDMENT TO CONVERTIBLE SECURED PROMISSORY NOTE

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EXHIBIT 10.25

                               FIFTH AMENDMENT TO

                       CONVERTIBLE SECURED PROMISSORY NOTE

      THIS FIFTH AMENDMENT TO CONVERTIBLE SECURED PROMISSORY NOTE (the "Fifth

Amendment") is made and entered into as of November 14, 2005, by and among

NORTHWEST BIOTHERAPEUTICS, INC., a Delaware corporation (the "Maker") and_______

(the "Holder"). This Fifth Amendment amends the Note (as defined below).

                                    RECITALS

A. Section 10 of that certain Convertible Secured Promissory Note, dated as of

November 12, 2003 and amended on April 26, 2004, April 12, 2005, June 16, 2005

and July 26, 2005, by and between the Maker and the Holder (as so amended the

"Note"), states that any provision of such note may be amended or waived in

writing by the Holder and the Maker; and

B. The Maker and the Holder wish to amend the Note as provided below.

                                    AGREEMENT

      NOW, THEREFORE, in consideration of these premise