Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
Abingworth Management LTD
  2. Issuer Name and Ticker or Trading Symbol
SUPERNUS PHARMACEUTICALS INC [SUPN]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
PRINCES HOUSE, 38 JERMYN STREET
3. Date of Earliest Transaction (Month/Day/Year)
05/04/2012
(Street)

LONDON, X0 SW1Y 6DN
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock, $0.001 par value per share 05/04/2012   C   2,500,000 A (1) 2,500,000 I (2) (3) See Notes (2) (3)
Common Stock, $0.001 par value per share 05/04/2012   P   1,100,000 (2) A $ 5 3,600,000 I (2) (3) See Notes (2) (3)

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Series A Convertible Preferred Stock (1) 05/04/2012   C     10,000,000 02/14/2006   (1) Common Stock 2,500,000 $ 1 0 I (2) (3) See Notes (2) (3)

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Abingworth Management LTD
PRINCES HOUSE
38 JERMYN STREET
LONDON, X0 SW1Y 6DN
    X    

Signatures

 /s/ John Heard, Authorized Signatory   05/08/2012
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) The 10,000,000 shares of Series A Convertible Preferred Stock, par value $0.001 per share ("Preferred Stock"), of Supernus Pharmaceuticals, Inc. (the "Issuer"), converted automatically into 2,500,000 shares of common stock, par value $0.001 per share ("Common Stock"), of the Issuer, without the payment to the Issuer of any consideration, upon the closing of the Issuer's initial public offering on May 4, 2012. The shares of Preferred Stock did not have an expiration date.
(2) Abingworth Management LTD (the "Reporting Person") is the investment manager to a number of investment funds that include Abingworth Bioventures IV LP ("ABV IV") and Abingworth Bioventures IV Executives LP ("ABV IV Execs," and together with ABV IV, the "Abingworth Funds"). On May 4, 2012, ABV IV purchased 1,090,650 shares of Common Stock and ABV IV Execs purchased 9,350 shares of Common Stock.
(3) Following the transactions reported herein, ABV IV holds 3,569,400 shares of Common Stock and ABV IV Execs holds 30,600 shares of Common Stock. The Reporting Person may be deemed to beneficially own the securities reported herein indirectly through the Abingworth Funds. The Reporting Person's interest in the securities reported herein is limited to the extent of its pecuniary interest, if any, in the Abingworth Funds. This report shall not be deemed an admission that the Reporting Person, either Abingworth Fund or any other person is the beneficial owner of the securities reported herein for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.

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