FOURTH AMENDMENT TO CONVERTIBLE SECURED PROMISSORY NOTE

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Exhibit 10.11

                               FOURTH AMENDMENT TO

                       CONVERTIBLE SECURED PROMISSORY NOTE

      THIS FOURTH AMENDMENT TO CONVERTIBLE SECURED PROMISSORY NOTE (the "FOURTH

AMENDMENT") is made and entered into as of July 26, 2005, by and among NORTHWEST

BIOTHERAPEUTICS, INC., a Delaware corporation (the "MAKER") and ______________

(the "HOLDER"). This 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 and June 16,

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 premises and for