UNITED STATES

SECURITIES AND EXCHANGE
COMMISSION

WASHINGTON, D.C.
20549



FORM 10-Q/A

AMENDMENT NO. 1



| | x | QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
SECURITIES EXCHANGE ACT OF 1934
| | - | ---------------------------------------------------------------------------------------



For the quarterly period ended March
31, 2014



OR



| |  ̈ | TRANSITION REPORT UNDER SECTION 13 OR 15(d) OF THE
SECURITIES EXCHANGE ACT OF 1934
| | - | ----------------------------------------------------------------------------------



For the transition period from ______to
_______



Commission File Number: 001-35737



NORTHWEST BIOTHERAPEUTICS, INC.

(Exact name of registrant
as specified in its charter)



|Delaware
        (State
        or Other Jurisdiction of Incorporation or Organization) | 94-3306718
        (I.R.S.
        Employer Identification No.)
|--------------------------------------------------------------------------------------- | ---------------------------------------------------------------





4800 Montgomery
Lane, Suite 800, Bethesda, MD 20814

(Address of principal
executive offices) (Zip Code)



(240) 497-9024

(Registrant's telephone
number)







Indicate by check mark whether the registrant (1) has filed
all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or
for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements
for the past 90 days. Yes x No  ̈









Indicate by check mark whether the registrant has submitted
electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant
to Rule 405 of Regulation S-T(§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the
registrant was required to submit and post such files). Yes x No  ̈



Indicate by check
mark whether the Registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or a smaller reporting
company. See definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting
company” in Rule 12b-2 of the Exchange Act.





|Large accelerated filer ̈                      | Accelerated filer ̈ | Non-accelerated filer ̈ | Smaller reporting companyx
|--------------------------------------------- | ------------------ | ---------------------- | --------------------------
|(do not check if a smaller reporting company)









Indicate by check mark whether the Registrant is a shell company
(as defined in Rule 12b-2 of the Exchange Act) Yes  ̈ No x







As of May 14, 2014,
the total number of shares of common stock, par value $0.001 per share, outstanding was 57,195,817.















NORTHWEST BIOTHERAPEUTICS, INC.



FORM 10-Q





EXPLANATORY NOTE



This Amendment No. 1 (“Amendment”)
on Form 10-Q/A amends the quarterly report on Form 10-Q of Northwest Biotherapeutics, Inc. (the “Company”) for the
period ended March 31, 2014, as filed with the Securities and Exchange Commission (the “Commission”) on May 15, 2014
(the “Form 10-Q”).





This Amendment is an exhibit-only filing solely for the purpose of filing revised versions of Exhibits 10.40,
10.41, 10.42 and 10.43. No revisions are being made to the Company’s financial statements and this Amendment does not reflect
events occurring after the filing of the Form 10-Q, or modify or update those disclosures that may be affected by subsequent events,
and no other changes are being made to any other disclosure contained in the Form 10-Q.













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Part II - Other Information









Item 6. Exhibits



|10.40* |  | DCVax®-L Manufacturing and Services Agreement, dated January 17, 2014, by
    and between Northwest Biotherapeutics, Inc. and Cognate BioServices, Inc. 
|------ |  | --------------------------------------------------------------------------------------------------------------------------------------------------------
|       |  |                                                                                                                                                         
|10.41* |  | DCVax®-Direct Manufacturing and Services Agreement, dated January 17, 2014, by and between Northwest Biotherapeutics, Inc. and Cognate BioServices, Inc.
|       |  |                                                                                                                                                         
|10.42* |  | Ancillary Services Agreement, dated January 17, 2014, by and between Northwest Biotherapeutics, Inc. and Cognate BioServices, Inc.                      
|       |  |                                                                                                                                                         
|10.43* |  | Manufacturing Expansion Services Agreement, dated January 17, 2014, by and between Northwest Biotherapeutics, Inc. and Cognate BioServices, Inc.        





|31.1 |  | Certification of President (Principal Executive Officer and Principal Financial and Accounting Officer), Pursuant to Exchange Act Rules 13a-14(a) and 15d-14(a), as Adopted Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
|---- |  | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | * | Confidential treatment has been requested with respect
to portions of this exhibit. Those portions have been omitted and filed separately with the SEC.
| | - | -------------------------------------------------------------------------------------------------------------------------------------------------------





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SIGNATURES



Pursuant to the requirements
of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned
thereunto duly authorized.



|                         | NORTHWEST BIOTHERAPEUTICS, INC
|------------------------ | ------------------------------
|                         |                               
|Dated: December 12, 2014 | By:                           
|                         |                               
|                         |                               
|                         |                               
|                         |                               















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