SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No. )*
Orexigen Therapeutics, Inc.
(Name of Issuer)
Common Stock, par value $0.001 per share
(Title of Class of Securities)
686164302
(CUSIP Number)
November 27, 2017
(Date of Event Which Requires Filing of This Statement)
Check the appropriate box to designate the rule pursuant to which this Schedule is filed:
¨	Rule 13d-1(b)
ý	Rule 13d-1(c)
¨	Rule 13d-1(d)
(Page 1 of 10 Pages)

______________________________

*The remainder of this cover page shall be filled out for a reporting person's initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

CUSIP No. 686164302 13G Page 2 of 10 Pages

1	NAME OF REPORTING PERSON Man GLG Select Opportunities Master LP
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP		(a) ¨ (b) ¨
3	SEC USE ONLY
4	CITIZENSHIP OR PLACE OF ORGANIZATION Cayman Islands
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:	5	SOLE VOTING POWER 0
	6	SHARED VOTING POWER 1,600,000
	7	SOLE DISPOSITIVE POWER 0
	8	SHARED DISPOSITIVE POWER 1,600,000
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,600,000
10	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES			¨
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 8.54%
12	TYPE OF REPORTING PERSON PN

CUSIP No. 686164302 13G Page 3 of 10 Pages

1	NAME OF REPORTING PERSON GLG LLC
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP		(a) ¨ (b) ¨
3	SEC USE ONLY
4	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:	5	SOLE VOTING POWER 0
	6	SHARED VOTING POWER 1,600,000
	7	SOLE DISPOSITIVE POWER 0
	8	SHARED DISPOSITIVE POWER 1,600,000
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,600,000
10	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES			¨
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 8.54%
12	TYPE OF REPORTING PERSON OO

CUSIP No. 686164302 13G Page 4 of 10 Pages

1	NAME OF REPORTING PERSON Man Group plc
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP		(a) ¨ (b) ¨
3	SEC USE ONLY
4	CITIZENSHIP OR PLACE OF ORGANIZATION United Kingdom
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:	5	SOLE VOTING POWER 0
	6	SHARED VOTING POWER 1,600,000
	7	SOLE DISPOSITIVE POWER 0
	8	SHARED DISPOSITIVE POWER 1,600,000
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,600,000
10	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES			¨
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 8.54%
12	TYPE OF REPORTING PERSON OO, HC

CUSIP No. 686164302 13G Page 5 of 10 Pages

Item 1(a).	NAME OF ISSUER:
	The name of the issuer is Orexigen Therapeutics, Inc., a Delaware corporation (the "Company").

Item 1(b).	ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES:
	The Company's principal executive offices are located at 3344 North Torrey Pines Court, Suite 200, La Jolla, California 92037.

Item 2(a).	NAME OF PERSON FILING:
	This statement is filed by the entities and persons listed below, who are collectively referred to herein as the "Reporting Persons" with respect to the Common Stock (as defined in Item 2(d) below):
	Fund:
	(i)	Man GLG Select Opportunities Master LP (the "GLG Fund"), with respect to the shares of Common Stock directly held by it.

Investment Manager:
(ii)	GLG LLC (the "Investment Manager"), with respect to the shares of Common Stock held by the GLG Fund to which the Investment Manager serves as investment manager.

Parent Company:
(iii)	Man Group plc (the "Parent Company"), which indirectly, through various intermediate entities, controls the Investment Manager, with respect to the shares of Common Stock held by the GLG Fund.

Item 2(b). ADDRESS OF PRINCIPAL BUSINESS OFFICE OR, IF NONE, RESIDENCE:

Item 2(c).	CITIZENSHIP:
	This statement is filed by:
	(i)	Man GLG Select Opportunities Master LP c/o GLG LLC HSBC Tower 452 Fifth Avenue New York, NY 10018 Citizenship: Cayman Islands

CUSIP No. 686164302 13G Page 6 of 10 Pages

(ii) GLG LLC HSBC Tower 452 Fifth Avenue New York, NY 10018 Citizenship: Delaware

(iii) Man Group Plc Riverbank House 2 Swan Lane London EC4R 3AD United Kingdom Citizenship: United Kingdom

The filing of this statement should not be construed as an admission that any of the Reporting Persons is, for the purposes of Sections 13 of the Securities Exchange Act of 1934, the beneficial owner of the shares of Common Stock reported herein.

Item 2(d).	TITLE OF CLASS OF SECURITIES:
	Common Stock, par value $0.001 per share (the "Common Stock").

Items 2(e).	CUSIP NUMBER:
	686164302

Item 3. IF THIS STATEMENT IS FILED PURSUANT TO RULES 13d-1(b) OR 13d-2(b) OR (c), CHECK WHETHER THE PERSON FILING IS A:

(a)	¨	Broker or dealer registered under Section 15 of the Act,
(b)	¨	Bank as defined in Section 3(a)(6) of the Act,
(c)	¨	Insurance Company as defined in Section 3(a)(19) of the Act,
(d)	¨	Investment Company registered under Section 8 of the Investment Company Act of 1940,
(e)	¨	An investment adviser in accordance with Rule 13d-1(b)(1)(ii)(E);
(f)	¨	Employee Benefit Plan or Endowment Fund in accordance with Rule 13d-1(b)(1)(ii)(F),
(g)	¨	Parent Holding Company or control person in accordance with Rule 13d-1(b)(1)(ii)(G),
(h)	¨	Savings Association as defined in Section 3(b) of the Federal Deposit Insurance Act,
(i)	¨	A church plan that is excluded from the definition of an investment company under Section 3(c)(14) of the Investment Company Act;
(j)	¨	A non-U.S. institution in accordance with Rule 13d-1(b)(1)(ii)(J);

CUSIP No. 686164302 13G Page 7 of 10 Pages

(k) ¨ Group, in accordance with Rule 13d-1(b)(1)(ii)(K).

If filing as a non-U.S. institution in accordance with Rule 13d-1(b)(1)(ii)(J), please

specify the type of institution: ________________________________

Item 4.	OWNERSHIP
	The information required by Items 4(a) – (c) is set forth in Rows (5) – (11) of the cover page for each Reporting Person hereto and is incorporated herein by reference for each such Reporting Person. The percentage set forth in Row (11) of the cover page for each Reporting Person is based on an aggregate of 18,739,099 shares of Common Stock currently outstanding which is the sum of (i) 16,603,831 shares of Common Stock outstanding as of November 10, 2017, as reported in the Company's Quarterly Report on Form 10-Q for the quarterly period ended September 30, 2017 filed with the Securities and Exchange Commission on November 14, 2017 and (ii) 2,135,268 shares of Common Stock issued by the Company in the exchange transactions described in the Company's Current Report on Form 8-K filed with the Securities and Exchange Commission on December 1, 2017.
	The Investment Manager, which serves as the investment manager to the GLG Fund, may be deemed to be the beneficial owner of all of the shares of Common Stock owned by the GLG Fund.  The Parent Company, which indirectly, through various intermediate entities, controls the Investment Manager, may be deemed to be the beneficial owner of all the shares of Common Stock owned by the GLG Fund. The Parent Company hereby disclaims any beneficial ownership of any such shares of Common Stock.

Item 5.	OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS.
	Not applicable.

Item 6.	OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON.
	Not applicable.

Item 7.	IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY.
	Not applicable.

Item 8.	IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP.
	Not applicable.

Item 9.	NOTICE OF DISSOLUTION OF GROUP.
	Not applicable.

CUSIP No. 686164302 13G Page 8 of 10 Pages

Item 10. CERTIFICATION.

Each of the Reporting Persons hereby makes the following certification:

By signing below each Reporting Person certifies that, to the best of its knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.

CUSIP No. 686164302 13G Page 9 of 10 Pages

SIGNATURES

After reasonable inquiry and to the best of its knowledge and belief, each of the undersigned certifies that the information set forth in this statement is true, complete and correct.

DATE: December 1, 2017

Man GLG Select Opportunities Master LP
By:	GLG LLC,
	its Investment Manager
By:  /s/ Eric Burl
Name: Eric Burl
Title: President
GLG LLC
By:  /s/ Eric Burl
Name: Eric Burl
Title: President
MAN GROUP PLC
By:  /s/ Michelle Robyn Grew
Name: Michelle Robyn Grew
Title: Chief Administrative Officer

CUSIP No. 686164302 13G Page 10 of 10 Pages

EXHIBIT I

JOINT FILING AGREEMENT

The undersigned acknowledge and agree that the foregoing statement on Schedule 13G is filed on behalf of each of the undersigned and that all subsequent amendments to this statement on Schedule 13G shall be filed on behalf of each of the undersigned without the necessity of filing additional joint filing agreements. The undersigned acknowledge that each shall be responsible for the timely filing of such amendments, and for the completeness and accuracy of the information concerning him or it contained herein and therein, but shall not be responsible for the completeness and accuracy of the information concerning the others, except to the extent that he or it knows or has reason to believe that such information is inaccurate.

DATED as of December 1, 2017

Man GLG Select Opportunities Master LP
By:	GLG LLC,
	its Investment Manager
By:  /s/ Eric Burl
Name: Eric Burl
Title: President
GLG LLC
By:  /s/ Eric Burl
Name: Eric Burl
Title: President
MAN GROUP PLC
By:  /s/ Michelle Robyn Grew
Name: Michelle Robyn Grew
Title: Chief Administrative Officer