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
OMB APPROVAL
OMB Number: 3235-0287
Expires: January 31, 2005
Estimated average burden hours per response... 0.5

(Print or Type Responses)
1. Name and Address of Reporting Person *
DUFFY MICHAEL P
   2. Issuer Name and Ticker or Trading Symbol
Lantheus Holdings, Inc. [LNTH] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
See Remarks
(Last)
(First)
(Middle)
C/O LANTHEUS HOLDINGS, INC., 331 TREBLE COVE ROAD		 3. Date of Earliest Transaction (Month/Day/Year)
04/03/2018
(Street)

NORTH BILLERICA, MA 01862		 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 04/03/2018   M(1)   27,313 A $ 5.62 191,472 D  
Common Stock 04/03/2018   S(1)   27,313 D $ 15.3003 (2) 164,159 D  

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number. SEC 1474 (9-02)

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
Stock Option (right to buy) $ 5.62 04/03/2018   M(1)     27,313   (3) 04/04/2018 Common Stock 27,313 $ 0 0 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
DUFFY MICHAEL P
C/O LANTHEUS HOLDINGS, INC.
331 TREBLE COVE ROAD
NORTH BILLERICA, MA 01862		       See Remarks  

Signatures

 /s/ Daniel Niedzwiecki, attorney-in-fact   04/05/2018
**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 transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on September 12, 2017.
(2) The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $15.05 to $15.65, inclusive. The reporting person undertakes to provide to Lantheus Holdings, Inc., ("LNTH") any security holder of LNTH or the staff of the Securities and Exchange Commission ("SEC"), upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote (2) to this Form 4.
(3) These options were originally granted on April 4, 2008, and originally provided for vesting based on the level of LNTH's satisfaction of certain performance criteria for each of fiscal years 2009, 2010, 2011 and 2012. As previously reported on a Form 4 filed with the SEC on June 25, 2015, these options were amended in connection with LNTH's initial public offering on June 25, 2015 to provide for additional vesting on the third anniversary of the amendment date (or the day before any earlier expiration) of any options that remain unvested at that time. As a result, these options became exercisable on April 3, 2018, one day prior to their expiration on April 4, 2018.
 
Remarks:
SVP, General Counsel and Secretary

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.

Potential persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB number.