Ownership Submission
FORM 3
 UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF 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 *
  Mezzino Maurice James
 2. Date of Event Requiring Statement (Month/Day/Year)
12/16/2015		 3. Issuer Name and Ticker or Trading Symbol
ARENA PHARMACEUTICALS INC [ARNA]
(Last)
(First)
(Middle)
C/O ARENA PHARMACEUTICALS, INC., 6154 NANCY RIDGE DRIVE		 4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
SVP, Corporate Development
 5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

SAN DIEGO, CA 92121		 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 Beneficially Owned
1.Title of Security
(Instr. 4)		 2. Amount of Securities Beneficially Owned
(Instr. 4)		 3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)		 4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Common Stock 8,763
D
 

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)		 2. Date Exercisable and Expiration Date
(Month/Day/Year)		 3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)		 4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)		 6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Employee Stock Option (right to buy)   (1) 09/15/2021 Common Stock 61,220 $ 1.48 D  
Employee Stock Option (right to buy)   (2) 10/03/2021 Common Stock 9,780 $ 1.48 D  
Employee Stock Option (right to buy)   (3) 03/19/2022 Common Stock 75,000 $ 1.81 D  
Employee Stock Option (right to buy)   (4) 03/05/2020 Common Stock 45,000 $ 8.54 D  
Employee Stock Option (right to buy)   (5) 03/03/2021 Common Stock 60,000 $ 6.8 D  
Employee Stock Option (right to buy)   (6) 03/11/2022 Common Stock 75,000 $ 4.47 D  

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Mezzino Maurice James
C/O ARENA PHARMACEUTICALS, INC.
6154 NANCY RIDGE DRIVE
SAN DIEGO, CA 92121		       SVP, Corporate Development  

Signatures

Adam S. Chinnock, as Attorney-in-Fact 12/18/2015
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(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 options originally for a total of 65,220 shares vested and became exercisable in four equal annual installments beginning on September 15, 2012.
(2) The options vested and became exercisable in four equal annual installments beginning on September 15, 2012.
(3) The options vest in four equal annual installments, and are exercisable once vested. The first installment became exercisable on March 19, 2013, the second installment became exercisable on March 19, 2014, the third installment became exercisable on March 19, 2015, and the fourth installment vests on March 19, 2016.
(4) The options vest in four equal annual installments, and are exercisable once vested. The first installment became exercisable on March 5, 2014, the second installment became exercisable on March 5, 2015, the third installment vests on March 5, 2016, and the fourth installment vests on March 5, 2017.
(5) The options vest in four equal annual installments, and are exercisable once vested. The first installment became exercisable on March 3, 2015, the second installment vests on March 3, 2016, the third installment vests on March 3, 2017, and the fourth installment vests on March 3, 2018.
(6) The options vest in four equal annual installments beginning on March 11, 2016, and are exercisable once vested.

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