UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549





FORM 10-Q/A

(Amendment No. 1)





(Mark One)

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

FOR THE QUARTERLY PERIOD ENDED September 30, 2015



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

FOR THE TRANSITION PERIOD FROM
                     TO

Commission file number: 001-33415





OREXIGEN
THERAPEUTICS, INC.

(Exact name of registrant as specified in its charter)



|                                                               |  |                                     
|-------------------------------------------------------------- |  | ------------------------------------
|Delaware                                                       |  | 65-1178822                          
|(State or Other Jurisdiction of
Incorporation or Organization) |  | (I.R.S. Employer
Identification No.)
|                                                               | 
|3344 North Torrey Pines Court, Suite 200, La Jolla, CA         |  | 92037                               
|(Address of Principal Executive Offices)                       |  | (Zip Code)                          

(858) 875-8600

(Registrants Telephone Number, Including Area Code)





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 registrant is a large accelerated filer, an accelerated filer, a
non-accelerated filer, or a smaller reporting company. See the definitions of large accelerated filer, accelerated filer, smaller reporting company in Rule 12b-2 of the Exchange Act.



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

Indicate by check mark whether registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).

 ̈  Yes    x 
 No

As of November 2, 2015, the registrant had 145,443,852 shares of Common Stock ($0.001 par value) outstanding.









---

EXPLANATORY NOTE

This Amendment No. 1 amends the Registrants Quarterly Report on Form 10-Q for the quarterly period ended September 30, 2015 (the
Report), originally filed with the U.S. Securities and Exchange Commission (the SEC) on November 9, 2015. The Registrant is filing this Amendment No. 1 solely to update Exhibit 10.1. The
Registrant sought confidential treatment for portions of the exhibit and, following correspondence with the SEC, has restored certain portions of the exhibit that were previously redacted.

Except as described above, no other changes have been made to the Report, and this Form 10-Q/A does not amend, update or change the financial statements
or disclosures in the Report. This Form 10-Q/A does not reflect events occurring after the filing of the Report or modify or update those disclosures. Accordingly, this Form 10-Q/A should be read in conjunction with our filings made with
the SEC subsequent to the filing of the Report, including any amendments to those filings.

In accordance with Rule 12b-15 under the Securities Exchange
Act of 1934, as amended, this Amendment No. 1 includes updated certifications from the Registrants Chief Executive Officer and Chief Financial Officer.



2



---

PART II  Other information

Item 6. Exhibits



|(a) | Exhibits
|--- | --------

The exhibits listed in the Report are required by Item 601 of Regulation S-K. A list of the
exhibits filed with this Form 10-Q/A is provided below.



|      |  |                                                                                                                                                  
|----- |  | -------------------------------------------------------------------------------------------------------------------------------------------------
|10.1* |  | Amended and Restated Collaboration Agreement, dated as of July 31, 2015, by and between the Registrant and Takeda Pharmaceutical Company Limited.
|      | 
|31.1  |  | Chief Executive Officers Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002                                                
|      | 
|31.2  |  | Chief Financial Officers Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002                                                
|      | 
|32.1  |  | Chief Executive Officers Certification pursuant to Section 906 of the Sarbanes Oxley Act of 2002                                                
|      | 
|32.2  |  | Chief Financial Officers Certification pursuant to Section 906 of the Sarbanes Oxley Act of 2002                                                



|* | Confidential treatment has been requested for certain portions, indicated by asterisks, omitted from this exhibit pursuant to Rule 24b-2 under the Securities Exchange Act of 1934, as amended. Confidential portions of
this exhibit have been separately filed with the Securities and Exchange Commission.
|- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



3



---

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.



|                       |  |  |  |                             |  |                                                                    
|---------------------- |  |  |  | --------------------------- |  | -------------------------------------------------------------------
|                       |  |  |  | OREXIGEN THERAPEUTICS, INC.
|                       |  |  | 
|Date: January 12, 2016 |  |  |  | By:                         |  | /s/ Michael A. Narachi                                             
|                       |  |  |  |                             |  | Michael A. Narachi                                                 
|                       |  |  |  |                             |  | President and Chief Executive Officer
(Principal Executive Officer)



|                       |  |  |  |     |  |                                                                                                        
|---------------------- |  |  |  | --- |  | -------------------------------------------------------------------------------------------------------
|                       |  |  | 
|Date: January 12, 2016 |  |  |  | By: |  | /s/ Stephen Moglia                                                                                     
|                       |  |  |  |     |  | Stephen Moglia Vice President and Chief
Accounting Officer (Principal Financial and Accounting Officer)



4



---

EXHIBIT INDEX



|               |  |                                                                                                                                                  
|-------------- |  | -------------------------------------------------------------------------------------------------------------------------------------------------
|Exhibit
Number |  | Description                                                                                                                                      
|               | 
|10.1*          |  | Amended and Restated Collaboration Agreement, dated as of July 31, 2015, by and between the Registrant and Takeda Pharmaceutical Company Limited.
|               | 
|31.1           |  | Chief Executive Officers Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002                                                
|               | 
|31.2           |  | Chief Financial Officers Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002                                                
|               | 
|32.1           |  | Chief Executive Officers Certification pursuant to Section 906 of the Sarbanes Oxley Act of 2002                                                
|               | 
|32.2           |  | Chief Financial Officers Certification pursuant to Section 906 of the Sarbanes Oxley Act of 2002                                                



|* | Confidential treatment has been requested for certain portions, indicated by asterisks, omitted from this exhibit pursuant to Rule 24b-2 under the Securities Exchange Act of 1934, as amended. Confidential portions of
this exhibit have been separately filed with the Securities and Exchange Commission.
|- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



5