Sarissa Capital Management SC 13D Aegerion Pharmaceuticals, Inc.

UNITED STATESSECURITIES AND EXCHANGE COMMISSIONWashington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No.   )*

Aegerion Pharmaceuticals, Inc.

(Name of Issuer)

Common Stock, $0.001 par value

(Title of Class of Securities)

00767E102

(CUSIP Number)

Mark DiPaolo

General Counsel

Sarissa Capital Management LP

660 Steamboat Road

Greenwich, CT 06830

203-302-2330

With a copy to:

Russell Leaf

Willkie Farr & Gallagher LLP

787 Seventh Avenue

New York, New York 10019

212-728-8000

(Name, Address and Telephone Number of PersonAuthorized to Receive Notices and Communications)

January 30, 2015

(Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition which is the subject of this Schedule 13D, and is filing this schedule because of Rule 13d-1(e), 13d-1(f) or 13d-1(g), check the following box. ☐

Note:  Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits.  See Rule 13d-7 for other parties to whom copies are to be sent.

*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 disclosures provided in a prior cover page.

The information required on 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 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.  00767E102 Page 2 of 10 Pages

SCHEDULE 13D

1	NAME OF REPORTING PERSON ORI.R.S. IDENTIFICATION NO. OF ABOVE PERSONSarissa Capital Management LP
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP			(a)  ☐     (b)  ☐
3	SEC USE ONLY
4	SOURCE OF FUNDSWC
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)			☐
6	CITIZENSHIP OR PLACE OF ORGANIZATIONDelaware
NUMBER OFSHARESBENEFICIALLYOWNED BYEACHREPORTINGPERSONWITH		7	SOLE VOTING POWER
		8	SHARED VOTING POWER1,637,455
		9	SOLE DISPOSITIVE POWER
		10	SHARED DISPOSITIVE POWER1,637,455
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON1,637,455
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES:			☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)5.76%
14	TYPE OF REPORTING PERSON PN

CUSIP No.  00767E102 Page 3 of 10 Pages

SCHEDULE 13D

1	NAME OF REPORTING PERSON ORI.R.S. IDENTIFICATION NO. OF ABOVE PERSONAlexander J. Denner
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP			(a)  ☐     (b)  ☐
3	SEC USE ONLY
4	SOURCE OF FUNDSWC
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)			☐
6	CITIZENSHIP OR PLACE OF ORGANIZATIONUnited States
NUMBER OFSHARESBENEFICIALLYOWNED BYEACHREPORTINGPERSONWITH		7	SOLE VOTING POWER
		8	SHARED VOTING POWER1,637,455
		9	SOLE DISPOSITIVE POWER
		10	SHARED DISPOSITIVE POWER1,637,455
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON1,637,455
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES:			☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)5.76%
14	TYPE OF REPORTING PERSON IN

CUSIP No.  00767E102 Page 4 of 10 Pages

SCHEDULE 13D

1	NAME OF REPORTING PERSON ORI.R.S. IDENTIFICATION NO. OF ABOVE PERSONSarissa Capital Offshore Master Fund LP
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP			(a)  ☐     (b)  ☐
3	SEC USE ONLY
4	SOURCE OF FUNDSWC
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)			☐
6	CITIZENSHIP OR PLACE OF ORGANIZATIONCayman Islands
NUMBER OFSHARESBENEFICIALLYOWNED BYEACHREPORTINGPERSONWITH		7	SOLE VOTING POWER643,547
		8	SHARED VOTING POWER
		9	SOLE DISPOSITIVE POWER643,547
		10	SHARED DISPOSITIVE POWER
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON643,547
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES:			☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)2.26%
14	TYPE OF REPORTING PERSON PN

CUSIP No.  00767E102 Page 5 of 10 Pages

SCHEDULE 13D

1	NAME OF REPORTING PERSON ORI.R.S. IDENTIFICATION NO. OF ABOVE PERSONSarissa Capital Domestic Fund LP
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP			(a)  ☐     (b)  ☐
3	SEC USE ONLY
4	SOURCE OF FUNDSWC
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)			☐
6	CITIZENSHIP OR PLACE OF ORGANIZATIONDelaware
NUMBER OFSHARESBENEFICIALLYOWNED BYEACHREPORTINGPERSONWITH		7	SOLE VOTING POWER993,908
		8	SHARED VOTING POWER
		9	SOLE DISPOSITIVE POWER993,908
		10	SHARED DISPOSITIVE POWER
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON993,908
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES:			☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)3.50%
14	TYPE OF REPORTING PERSON PN

CUSIP No.  00767E102 Page 6 of 10 Pages

SCHEDULE 13D

Item 1.  Security and Issuer.

This statement relates to the Common Stock, par value $0.001 (the “Shares”), issued by Aegerion Pharmaceuticals, Inc. (the “Issuer”). The address of the principal executive offices of the Issuer is One Main Street, Suite 800, Cambridge, Massachusetts 02142.

Item 2.  Identity and Background.

The persons filing this statement are Sarissa Capital Management LP, a Delaware limited partnership (“Sarissa Capital”), Sarissa Capital Offshore Master Fund LP, a Cayman Islands exempted limited partnership (“Sarissa Offshore”), Sarissa Capital Domestic Fund LP, a Delaware limited partnership (“Sarissa Domestic”), and Alexander J. Denner, Ph.D., a citizen of the United States of America (collectively, the “Reporting Persons”).

The principal business address of (i) each of Sarissa Capital, Sarissa Domestic and Dr. Denner is c/o Sarissa Capital Management LP, 660 Steamboat Road, 3^rd Floor, Greenwich, CT 06830 and (ii) Sarissa Offshore is c/o Ogier Fiduciary Services (Cayman) Limited, 89 Nexus Way, Camana Bay, Grand Cayman KY1-9007, Cayman Islands.

Sarissa Capital’s principal business is serving as investment advisor to private investment funds, including Sarissa Domestic and Sarissa Offshore (collectively, the “Sarissa Funds”).  The ultimate general partner of each of Sarissa Capital, Sarissa Domestic and Sarissa Offshore is controlled by Dr. Denner.  Dr. Denner’s principal occupation is serving as the Chief Investment Officer of Sarissa Capital.

The name, citizenship, present principal occupation or employment and business address of each director and executive officer of the Reporting Persons are set forth in Schedule A attached hereto.

None of the Reporting Persons nor any manager or executive officer of the Reporting Persons, has, during the past five years, (a) been convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors), or (b) been a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting, or mandating activities subject to, Federal or State securities laws or a finding of any violation with respect to such laws.

Item 3.  Source or Amount of Funds or Other Consideration.

The Reporting Persons may be deemed to be the beneficial owner of, in the aggregate, 1,637,455 Shares. The aggregate purchase price of the Shares purchased by the Reporting Persons collectively was approximately $39.7 million (including commissions). The source of funding for these Shares was the general working capital of the respective purchasers.

Item 4.  Purpose of Transaction.

The Reporting Persons acquired the Shares with the belief that the Shares were undervalued.  The Reporting Persons expect to engage in discussions with the Issuer regarding its investment in the Shares.  The Reporting Persons will continue to review their investment on an on-going basis and reserve the right to, from time to time and at any time: (i) acquire additional Shares and/or other equity, debt, notes, instruments or other securities (collectively, “Securities”) of the Issuer in the open market or otherwise; (ii) dispose of any or all of their Securities in the open market or otherwise; or (iii) engage in any hedging or similar transactions with respect to the Securities.

CUSIP No.  00767E102 Page 7 of 10 Pages

SCHEDULE 13D

Item 5.  Interest in Securities of the Issuer.

(a) The Reporting Persons may be deemed to beneficially own, in the aggregate, 1,637,455 Shares representing approximately 5.76% of the Issuer's outstanding Shares (based upon the 28,435,998 Shares stated to be outstanding as of October 31, 2014 by the Issuer in the Issuer’s Form 10−Q for the quarterly period ended September 30, 2014).

(b) For purposes of this Schedule 13D:

Sarissa Domestic has sole voting power and sole dispositive power with regard to 993,908 Shares.  Sarissa Offshore has sole voting power and sole dispositive power with regard to 643,547 Shares.  Sarissa Capital, as the investment advisor to the Sarissa Funds, may be deemed to have the shared power to vote or direct the vote of (and the shared power to dispose or direct the disposition of) the 1,637,455 Shares held by the Sarissa Funds.  By virtue of his position as the Chief Investment Officer of Sarissa Capital and as the managing member of Sarissa Capital’s general partner, Dr. Denner may be deemed to have the shared power to vote or direct the vote of (and the shared power to dispose or direct the disposition of) the 1,637,455 Shares held by the Sarissa Funds.

(c) The following table sets forth all transactions with respect to Shares effected during the past sixty (60) days by any of the Reporting Persons, inclusive of any transactions effected through 4:00 p.m., New York City time, on February 4, 2015. Except as otherwise noted below, all such transactions were purchases of Shares effected in the open market.

Name of Reporting Person	Date of Transaction	Amount of Securities	Price Per Share ($)
Sarissa Domestic	January 14, 2015	106,243	24.18
Sarissa Domestic	January 15, 2015	51,389	23.0
Sarissa Domestic	January 20, 2015	133,794	24.94
Sarissa Domestic	January 21, 2015	101,395	24.31
Sarissa Domestic	January 22, 2015	91,860	24.4
Sarissa Domestic	January 23, 2015	121,428	24.66
Sarissa Domestic	January 26, 2015	145,713	24.93
Sarissa Domestic	January 29, 2015	103,213	23.45
Sarissa Domestic	January 30, 2015	121,425	23.27
Sarissa Domestic	February 3, 2015	4,003	23.31
Sarissa Domestic	February 4, 2015	13,445	23.33
Sarissa Offshore	January 14, 2015	68,757	24.18
Sarissa Offshore	January 15, 2015	33,242	23.0
Sarissa Offshore	January 20, 2015	86,575	24.94
Sarissa Offshore	January 21, 2015	65,610	24.31
Sarissa Offshore	January 22, 2015	59,440	24.4
Sarissa Offshore	January 23, 2015	78,572	24.66
Sarissa Offshore	January 26, 2015	94,287	24.93
Sarissa Offshore	January 29, 2015	66,787	23.45
Sarissa Offshore	January 30, 2015	78,575	23.27
Sarissa Offshore	February 3, 2015	2,997	23.31
Sarissa Offshore	February 4, 2015	8,705	23.33

CUSIP No.  00767E102 Page 8 of 10 Pages

SCHEDULE 13D

Item 6.  Contracts, Arrangements, Understandings or Relationships with Respect to Securities of the Issuer.

Except as otherwise described herein, there are no contracts, arrangements, understandings or relationships (legal or otherwise) among the persons named in Item 2 and between such persons and any person with respect to any securities of the Issuer, including but not limited to transfer or voting of any of the securities, finder's fees, joint ventures, loan or option arrangements, puts or calls, guarantees of profits, division of profits or loss, or the giving or withholding of proxies.

Item 7.  Material to Be Filed as Exhibits.

1Joint Filing Agreement of the Reporting Persons

CUSIP No.  00767E102 Page 9 of 10 Pages

SCHEDULE 13D

SIGNATURE

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

Dated:  February 5, 2015

SARISSA CAPITAL MANAGEMENT LP

By:	/s/ Mark DiPaolo
	Name: Mark DiPaolo
	Title: General Counsel

SARISSA CAPITAL DOMESTIC FUND LP

By: Sarissa Capital Fund GP LP, its general partner

By:	/s/ Mark DiPaolo
	Name: Mark DiPaolo
	Title: Authorized Person

SARISSA CAPITAL OFFSHORE MASTER FUND LP

By: Sarissa Capital Offshore Fund GP LLC, its general partner

By:	/s/ Mark DiPaolo
	Name: Mark DiPaolo
	Title: Authorized Person

/s/Alexander J. Denner________________________Alexander J. Denner

CUSIP No.  00767E102 Page 10 of 10 Pages

SCHEDULE 13D

SCHEDULE A

DIRECTORS AND EXECUTIVE OFFICERS OF THE REPORTING PERSONS

The following sets forth the name, position, and principal occupation of each director and executive officer of each of the Reporting Persons. Each such person is a citizen of the United States of America. Except as otherwise indicated, the business address of each director and officer is c/o Sarissa Capital Management LP, 660 Steamboat Road, 3^rd Floor, Greenwich, CT 06830. To the best of the Reporting Persons' knowledge, except as set forth in this statement on Schedule 13D, none of the directors or executive officers of the Reporting Persons own any Shares.

SARISSA CAPITAL MANAGEMENT LP

SARISSA CAPITAL DOMESTIC FUND LP

SARISSA CAPITAL OFFSHORE MASTER FUND LP

Name	Position
Alexander J. Denner, Ph.D.	Chief Investment Officer
Richard Mulligan, Ph.D.	Senior Managing Director
Mayu Sris	Managing Director
Mark DiPaolo	General Counsel and Chief Compliance Officer
Patrice Bonfiglio	Chief Financial Officer
Fredrik Guster	Head of Strategy and Business Development
Richard Giroux	Head Trader