UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

(Amendment No.    )

Filed by the Registrant  ☒                            Filed by a Party other than the Registrant  ☐

Check the appropriate box:

LANTHEUS HOLDINGS, INC.

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

March 16, 201815, 2019

To Our Stockholders:

We cordially invite you to attend Lantheus Holdings, Inc.’s 20182019 Annual Meeting of Stockholders, to be held on Thursday,Wednesday, April 26, 201824, 2019 at 11:00 a.m. (Eastern Time) at the DoubleTree—Bedford Glen, located at 44 Middlesex Turnpike, Bedford, MA 01730.

The Notice of Internet Availability of Proxy Materials and the proxy statement that follow describe the business to be conducted at the meeting.

Your vote is important. We encourage you to vote by proxy in advance of the meeting, whether or not you plan to attend the meeting. On behalf of the Board of Directors, thank you for your continued investment in our company.

Sincerely,

Brian Markison

Chairman of the Board of Directors

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

We are holding our 20182019 Annual Meeting of Stockholders for the following purposes, which are described in more detail in the proxy statement, to:

At the meeting, we will also transact any other business as may properly come before the meeting or any adjournment or postponement thereof. Only stockholders of record as of the close of business on February 26, 20182019 will be entitled to attend and vote at the meeting.

We are pleased to take advantage of the Securities and Exchange Commission rules that allow companies to furnish their proxy materials over the Internet. We are sending to most of our stockholders a Notice of Internet Availability of Proxy Materials (the “Notice”) instead of paper copies of our proxy materials and our 20172018 Annual Report on Form10-K. The Notice contains instructions on how to access those documents and to cast your vote via the Internet. The Notice also contains instructions on how to request a paper copy of our proxy materials and our Annual Report. All stockholders who do not receive the Notice will receive a paper copy of the proxy materials and the Annual Report by mail. This process allows us to provide our stockholders with the information they need on a more timelytimelier basis, while lowering the costs of printing and distributing our proxy materials and reducing the environmental impact.

Your vote is important. We encourage you to vote by proxy in advance of the meeting, whether or not you plan to attend the meeting. The proxy statement includes instructions on how to vote, including by Internet and telephone. If you hold your shares through a brokerage firm, bank, broker-dealer or other similar organization, please follow their instructions.

By order of the Board of Directors,

Daniel M. NiedzwieckiMichael P. Duffy

Senior Vice President, Deputy General Counsel and

Assistant Secretary

March 16, 201815, 2019

Important Notice Regarding the Availability of Proxy Materials for the Annual Meeting of

Stockholders to be held on April 26, 2018.24, 2019.

The Lantheus Holdings, Inc. Proxy Statement and Annual Report are available at  http://www.proxydocs.com/lnth.

TABLE OF CONTENTS

PROXY STATEMENT

20182019 ANNUAL MEETING OF STOCKHOLDERS

TO BE HELD ON APRIL 26, 201824, 2019

GENERAL INFORMATION

The Board of Directors (the “Board”) is making this proxy statement available to you on the Internet, or at your request has delivered printed versions to you by mail, in connection with the solicitation of proxies by the Board for our 20182019 Annual Meeting of Stockholders to be held on Thursday,Wednesday, April 26, 201824, 2019 at 11:00 a.m. (Eastern Time) at the DoubleTree—Bedford Glen, located at 44 Middlesex Turnpike, Bedford, MA 01730, and any adjournment or postponement of that meeting (the “Annual Meeting”). If you requested printed versions of these materials by mail, they will also include a proxy card for the Annual Meeting.

Pursuant to rules adopted by the Securities and Exchange Commission (“SEC”), we are providing access to our proxy materials over the Internet. Accordingly, we are sending a Notice of Internet Availability of Proxy Materials (the “Notice”) to our stockholders of record and beneficial owners as of the record date identified below. The mailing of the Notice to our stockholders is scheduled to begin on or about March 16, 2018.15, 2019.

IMPORTANT NOTICE REGARDING THE INTERNET AVAILABILITY OF PROXY MATERIALS

FOR THE ANNUAL STOCKHOLDERS MEETING TO BE HELD ON APRIL 26, 2018:24, 2019:

This Proxy Statement, the accompanying proxy card or voting instruction card and

our 20172018 Annual Report on Form10-K are each available at http://www.proxydocs.com/lnth.

In this proxy statement, unless the context requires otherwise, the words “Lantheus,” “Company,” “we,” “us” and “our” refer to Lantheus Holdings, Inc. and its subsidiaries. The mailing address of our principal executive offices is Lantheus Holdings, Inc., 331 Treble Cove Road, North Billerica, MA 01862.

In this proxy statement, we indicate that certain materials are available on our Investor Relations website at http://investor.lantheus.com. The information on our website is not part of, and is not incorporated into, this proxy statement.

EXPLANATORY NOTE

We are an “emerging growth company,” as defined in the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”), and we are, therefore, permitted to, and we intend to rely on, exemptions from certain disclosure requirements applicable to other public companies. For example, we are not required to provide our stockholders with the opportunity to vote on certain executive compensation matters on anon-binding advisory basis.

We will remain an emerging growth company until December 31, 2020 unless, prior to that time, we (i) have more than $1.07 billion in annual revenue, (ii) have a market value for our common stock held bynon-affiliates of more than $700 million as of the last day of our second fiscal quarter of the fiscal year when a determination is made that we are deemed to be a “large accelerated filer,” as defined in Rule12b-2 promulgated under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or (iii) issue more than $1 billion ofnon-convertible debt over a three-year period.

QUESTIONS AND ANSWERS ABOUT THE ANNUAL MEETING

Below are answers to common questions stockholders may have about the Proxy Materials and the Annual Meeting.

What are the Proxy Materials?

The “Proxy Materials” consist of the Notice, this proxy statement, our Annual Report on Form10-K for the fiscal year ended December 31, 20172018 and (if you request paper copies) a proxy card/voting instruction form.

What items will be voted on at the Annual Meeting and how does the Board of Directors recommend that I vote?

There are fivethree proposals to be voted on at the Annual Meeting, to:

Our amended and restated bylaws require that we receive advance notice of any proposals to be brought before the Annual Meeting by our stockholders. We have not received any such proposals. We do not anticipate any other matters will come before the Annual Meeting. If any other matter properly comes before the Annual Meeting, the proxy holders appointed by the Board of Directors will have discretion to vote on those matters.

The Board of Directors recommends that you vote

“FOR” each of the nominees in Proposal 1 and

“FOR” Proposals 2 3, 4 and 5.3.

Who may vote at the meeting?

Holders of shares of our common stock (“Shares”) as of the close of business on February 26, 20182019 (the “Record Date”) may vote at the Annual Meeting.

How many Shares may be voted at the Annual Meeting?

Only stockholders of record as of the close of business on the Record Date will be entitled to vote at the Annual Meeting. As of the close of business on the Record Date, there were 37,928,33238,628,501 Shares entitled to vote at the Annual Meeting.

How many votes do I have?

Holders of our common stock are entitled to one vote for each Share held as of the Record Date.

How are abstentions and brokernon-votes counted?

Abstentions (that is, Shares present at the meeting in person or by proxy that are voted “ABSTAIN”) and brokernon-votes (explained below) are counted for the purpose of establishing the presence of a quorum, but are not counted as votes cast “FOR” or “AGAINST”. However, since the approval of Proposal 2 requires at least two thirds of the votes entitled to be cast, and Proposals 3 and 4 require at least a majority of the votes entitled to be cast, an abstention from voting or a brokernon-vote will have the same effect as a vote against those proposals.“AGAINST.”

What is the difference between a stockholder of record and a beneficial owner of Shares held in street name?

Stockholder of Record.If your Shares are registered directly in your name with our transfer agent, Computershare, then you are a “stockholder of record.”

Beneficial Owner of Shares Held in Street Name.If your Shares are held in an account at a brokerage firm, bank, broker-dealer or other similar organization, then you are a “beneficial owner of Shares” held in “street name.” In that case, the organization holding your account is considered the stockholder of record. As a beneficial owner, you have the right to direct the organization holding your account on how to vote the Shares you hold in your account.

How do stockholders of record vote?

There are four ways for stockholders of record to vote:

If I hold Shares in street name through a broker, can the broker vote my shares for me?

If you hold your Shares in street name and you do not vote, the broker or other organization holding your Shares can vote on certain “routine” proposals but cannot vote on other proposals.

Who is paying for this proxy solicitation?

The Company is paying the costs of the solicitation of proxies. Members of the Board, of Directors and officers and employees and, potentially, Alliance Advisors, a third party proxy solicitor, may solicit proxies by mail, telephone, fax, email or in person. We will not pay directors, officers or employees any extra amounts for soliciting proxies. If we decide to retain a third party proxy solicitor, we would not expect to pay it more than $10,000 for any proxy solicitation services it renders. We may, upon request, reimburse brokerage firms, banks or similar entities representing street name holders for their expenses in forwarding Proxy Materials to their customers who are street name holders and obtaining their voting instructions. If you choose to access the Proxy Materials or vote over the Internet, you are responsible for any Internet access charges that you may incur.

What do I need to do if I want to attend the meeting?

You will need to provide evidence that you are a stockholder as of the Record Date. This can be a copy of your proxy card or a brokerage statement showing your Shares.Shares as of the Record Date. You should also bring photo identification. If you hold your Shares in street name and wish to vote in person at the meeting, you will need to contact the organization that holds your Shares in order to obtain a legal proxy from that organization.

Where can I find voting results?

We will file a Current Report on Form8-K with the SEC to report the final voting results from the Annual Meeting within four business days of the Annual Meeting.

What are the implications of being an “emerging growth company”?

We are an “emerging growth company,” as defined in the JOBS Act, and we are, therefore, permitted to, and we intend to rely on,upon, exemptions from certain disclosure requirements applicable to other public companies. For example, we are not required to provide our stockholders with the opportunity to vote on certain executive compensation matters on anon-binding advisory basis.

We will remain an emerging growth company until December 31, 2020 unless, prior to that time, we (i) have more than $1.07 billion in annual revenue, (ii) have a market value for our common stock held bynon-affiliates of more than $700 million as of the last day of our second fiscal quarter of the fiscal year when a determination is made that we are deemed to be a “large accelerated filer,” as defined in Rule12b-2 promulgated under the Exchange Act or (iii) issue more than $1 billion ofnon-convertible debt over a three-year period.

Who should I contact if I have additional questions?

You can contact our Investor Relations department at978-671-8508978-671-8842 or ir@lantheus.com or by writing to Lantheus Holdings, Inc., 331 Treble Cove Road, North Billerica, MA 01862, Attention: Investor Relations. Stockholders who hold their Shares in street name should contact the organization that holds their Shares for additional information on how to vote.

PROPOSAL 1: ELECTION OF DIRECTORS

The Board of Directors is currently comprised of ten directors. In accordance with our Charter,Amended and Restated Certificate of Incorporation (our “Charter”), our Board consists of three classes: Class I, Class II and Class III, with terms expiring in 2019, 2020 and 2018,2021, respectively. Messrs. Brian Markison, Gary Pruden and Kenneth PucelMs. Mary Anne Heino, Mr. Samuel Leno and Dr. James ThrallDerace Schaffer are the Class IIII directors whose terms expire at the Annual Meeting. Our Board has nominated, and stockholders are being asked to elect, Messrs. Markison, Pruden and PucelMs. Heino, Mr. Leno and Dr. ThrallSchaffer for three-year terms expiring at our 20212022 Annual Meeting of Stockholders. If elected, each of the nominees will hold office until our 20212022 Annual Meeting of Stockholders and a successor is duly elected and qualified or until her or his earlier death, resignation or removal.

The persons named as proxies will vote to elect each of these fourthree nominees, unless a stockholder indicates that his or her Shares should be withheld with respect to any one or more of these nominees.

In the event that any nominee for director becomes unavailable or declines to serve as a director at the time of the Annual Meeting, the persons named as proxies will vote the proxies in their discretion for any nominee who is designated by the current Board of Directors to fill the vacancy. We do not expect that any of the nominees will be unavailable or will decline to serve.

In determining that each director should be nominated for election, the Board of Directors considered her or his service, business experience, prior directorships, qualifications, attributes and skills described in the biography set forth below under “Corporate Governance—Executive Officers and Directors.Directors” and the criteria and diversity policy described under “Director Nomination Process and Diversity Policy.”

Vote Required

ForUnder Delaware law and our bylaws, if a quorum exists at the electionmeeting, the affirmative vote of Class III directors, each director must be elected by a plurality of the votes cast.cast at the meeting is required for the election of Class I directors. This means that the fourthree nominees receiving the largest number of “FOR” votes will be elected as Class IIII directors. We do not have cumulative voting.

Majority Voting Policy To Take Effect at Next Annual Meeting

On October 18, 2018, upon the recommendation of our Nominating and Corporate Governance Committee, our Board adopted a majority voting policy, providing that in the case of an uncontested election of directors in which a director nominee does not receive votes affirmatively cast “FOR” his or her election orre-election in excess of 50% of the number of votes cast with respect to that nominee’s election orre-election, that director will contingently tender his or her resignation, which, in accordance with the majority voting policy, the Board may in its sole discretion elect to accept. The majority voting policy will take effect beginning with the election of our Class II directors at our annual stockholders meeting in 2020.

Board of Directors’ Recommendation

THE BOARD OF DIRECTORS RECOMMENDS THAT YOU VOTE “FOR” EACH OF THE DIRECTOR

NOMINEES IN THIS PROPOSAL 1.

CORPORATE GOVERNANCE

Executive Officers and Directors

The following table sets forth information regarding our current executive officers and directors, including their ages as of the date of this proxy statement.

Brian Markison is theNon-Executive Chairman of the Board of Directors and Chair of the Financing and Strategy Committee. Mr. Markison joined the Board of Directors in September 2012 and was elevated to Chairman in January 2013. Mr. Markison has been a Healthcare Industry Executive for Avista Capital Partners since September 2012. Mr. Markison is a seasoned executive with more than 30 years of operational, marketing, commercial development and sales experience with international pharmaceutical companies. He is currently the Chief Executive Officer and a Director of Osmotica Holdings, SCSp,S.C.Sp., after serving as Executive Chairman of one of its predecessor companies, Vertical/Trigen Holdings, LLC. Previously, he held the position of President and Chief Executive Officer and member of the Board of Directors of Fougera Pharmaceuticals Inc., a specialty pharmaceutical company in dermatology, prior to its sale to Sandoz, the generics division of Novartis AG. Before leading Fougera, Mr. Markison was Chairman and Chief Executive Officer of King Pharmaceuticals, which he joined as Chief Operating Officer in March 2004, and was promoted to President and Chief Executive Officer later that year and elected Chairman in 2007. Prior to joining King, Mr. Markison held various senior leadership positions at Bristol-Meyers Squibb, including President of Oncology, Virology and Oncology Therapeutics Network; President of Neuroscience, Infectious Disease and Dermatology; and Senior Vice President, Operational Excellence and Productivity. Mr. Markison also serves on the Board of Directors of Immunomedics, Inc., on the Board of Directors of National Spine Centers LLC, on the Board of Directors of Braeburn Pharmaceuticals, and as Chairman ofon the Board of Directors for Rosetta Genomics, Ltd.of Cosette Pharmaceuticals. He is also a Director of the College of New Jersey. Mr. Markison holds a Bachelor of Science degree from Iona College. Mr. Markison was chosen as a Director because of his strong commercial and operational management background and extensive experience in the pharmaceutical industry.

James C. Clemmer is a Director and a member of the Audit Committee and the Compensation Committee, serving on the Board of Directors since July 2015. He is a seasoned industry executive with more than 25 years of

of operational, manufacturing, marketing and business development experience with global healthcare product companies. Mr. Clemmer is President and Chief Executive Officer of AngioDynamics Inc., a medical device manufacturer based in Latham, New York. He previously served as President of the Medical Supplies segment at Covidien plc, directing strategic andday-to-day operations for global business divisions that collectively manufactured 23 different product categories. In addition, Mr. Clemmer managed global manufacturing, research and development, operational excellence, business development and all other functions associated with the Medical Supplies business. Mr. Clemmer is a graduate of the Massachusetts College of Liberal Arts. Mr. Clemmer served as a trustee to the college and as Interim President. Mr. Clemmer was chosen as a Director because of his strong commercial and operational management background and extensive experience in the healthcare industry.

Samuel Leno is a Director and the Chairperson of the Audit Committee and member of the Financing and Strategy Committee, serving on the Board of Directors since May 2012. Mr. Leno is a strategic executive with more than 40 years of experience with complex multinational companies. He most recently held the positions of Executive Vice President and Chief Operations Officer at Boston Scientific. He previously served as Executive Vice President, Finance and Information Systems and Chief Financial Officer. He retired from Boston Scientific in December 2011. Prior to joining Boston Scientific, Mr. Leno served as Executive Vice President, Finance and Corporate Services and Chief Financial Officer at Zimmer Holdings, Inc. and Chief Financial Officer positions at Arrow Electronics, Inc., Corporate Express, Inc. and Coram Healthcare. Previously, he held a variety of senior financial positions at Baxter International, Inc. and American Hospital Supply Corporation. He iswas the Chairman of the Board of Directors and of the Audit Committee of Zest Anchors, Inc.Dental Solutions until it was acquired in 2018. He also previously served on the Boards of Directors and the Audit Committees of Omnicare and TomoTherapy, Inc. and also served on the Board of Directors of Endotronix, Inc. Mr. Leno served as a Lieutenant in the United States Navy and is a Vietnam veteran. He holds a Bachelor of Science in Accounting from Northern Illinois University and a Master of Business Administration from Roosevelt University. Mr. Leno was chosen as a Director because of his financial expertise and industry background.

Julie McHughis a Director and the Chairperson of the Compensation Committee, serving on the Board of Directors since January 2017. Ms. McHugh brings over 30 years of experience in the pharmaceutical, biotech and medical devices industries. She recently served as Chief Operating Officer of Endo Health Solutions, Inc., where she was responsible for the specialty pharmaceutical and generic drug businesses. Prior to that, Ms. McHugh was CEO of Nora Therapeutics, Inc., a venture capital backed biotech startup company focused on developing novel therapies for the treatment of infertility disorders. Previously, she served as Company Group Chairman for Johnson & Johnson’sthe worldwide virology business unit of Johnson & Johnson (“J&J”), and prior to that, she was President of Centocor, Inc., a J&J subsidiary. In this role, Ms. McHugh oversaw the development and launches of several products, including Remicade^® (infliximab), Prezista^® (darunavir) and Intelence^® (etravirine). Prior to joining Centocor, Ms. McHugh led the marketing communications for gastrointestinal drug Prilosec^® (omeprazole) at Astra-Merck Inc. Ms. McHugh currently serves on the Board of Directors and as a member of the Nominating and Governance Committee and Audit Committee of Aerie Pharmaceuticals, Inc., on the Board of Directors and as Chairperson of the Nominating and Governance Committee and Audit Committee of Ironwood Pharmaceuticals, Inc., and on the Boards of Directors of New Xellia Group A/S and Trevena Pharmaceuticals, Inc. Ms. McHugh also serves as a member of the Strategic Advisor Board for HealthCare Royalty Partners. She previously served on the Board of Directors of the Biotechnology Industry Organization, the New England Healthcare Institute, the Pennsylvania Biotechnology Association, EPIRUS Pharmaceuticals, Inc. and ViroPharma Inc. Ms. McHugh received a Master of Business Administration from St. Joseph’s University and a Bachelor of Science from Pennsylvania State University. Ms. McHugh was chosen as a Director because of her strong commercial and operational management background and extensive experience in the pharmaceutical industry.

Gary J. Prudenis a Director and a member of the Audit Committee and the Financing and Strategy Committee, serving on the Board of Directors since February 2018. Mr. Pruden has over 30 years of experience in the global healthcare industry. Most recently, Mr. Pruden held a number of senior commercial leadership positions across both the medical device and pharmaceutical sectors of Johnson & Johnson (“J&J”)&J from 1985

appointed as a member of the Executive Committee of J&J, where his official title was Executive Vice President, Worldwide Chairman, Medical Devices. Prior to that, he held roles of increasing responsibility within J&J, serving as Worldwide Chairman in the Medical Devices division from 2015 to 2016, as Worldwide Chairman of Global Surgery Group from 2012 to 2015, as Company Group Chairman of Ethicon, Inc. from 2009 to 2012, as Worldwide President of Ethicon, Inc., a J&J subsidiary, from 2006 to 2009, and as President of the J&J subsidiary, Janssen-Ortho Inc. in Canada, from 2004 to 2006. Mr. Pruden has also served in several capacities, including Chairman of Technology & Regulatory Committee and Executive Committee Member, with the Advanced Medical Technology Association, a medical device trade association. Mr. Pruden currently serves on the Board of Directors and as a member of the Audit Committee and Compensation Committee of Motus GI Holdings, Inc. Mr. Pruden received his Bachelor of Science in Finance at Rider University, where he later served on the Board of Trustees from 2011 until 2015. Mr. Pruden was selected as a Director because of his strong financial, operational management, international and regulatory background and his extensive experience in the global pharmaceutical industry.

Kenneth J. Pucelis a Director and a member of the Compensation Committee, serving on the Board of Directors since February 2018. Mr. Pucel has been an Executive Vice President of Global Operations, Engineering & Lean, at Polaris Industries Inc. since December 1, 2014. There, Mr. Pucel is responsible for all aspects of Polaris manufacturing operations, including production, quality, supply chain, and logistics and inventory for Polaris’ 12 global factories.Polaris. He is also responsible for all aspects of Research and Development for PolarisOff-Road,On-Road andOn-Road Defense vehicles. Previously, Mr. Pucel was with Boston Scientific, Corporation (“BSC”), a global provider of medical solutions, where he held positions of increasing responsibility, most recently as Executive Vice President of Global Operations, Quality and Technology from 2012 through 2014, and as a member of BSC’sBoston Scientific’s Executive Committee from 2004 through 2014. Mr. Pucel holds a Bachelor of Science in Mechanical Engineering with a focus on Biomedical Engineering from the University of Minnesota. Mr. Pucel was selected as a Director because of his strong operational management background and extensive experience in manufacturing, supply chains and distribution.

Dr. Frederick Robertson is a Director and a member of the Audit Committee and the Chairperson of the Nominating and Corporate Governance Committee, serving on the Board of Directors since March 2016. Dr. Robertson has been a Venture Partner at Baird Capital since 2011 and has also served as an Assistant Professor ofretired from the Anesthesiology Faculty at the University of Wisconsin School of Medicine and Public Health since 2012.in 2018. Previously, Dr. Robertson held the role of Chief Executive Officer and Director of TomoTherapy Inc. before that company was acquired in 2011. Prior to joining TomoTherapy, Dr. Robertson served in a variety of roles in the medical field, including President and Chief Executive Officer of GE Marquette Medical Systems and later as Chief Clinical Officer of GE Medical Systems, as well as management positions with Marquette Medical Systems, including President and Chief Executive Officer. He serves on the Board of Directors of the University of Wisconsin Foundation, the Morgridge Institute for Research, Alpha Source, Inc. and Zurex Pharma, Inc. Dr. Robertson received his Master of Business Administration from San Diego State University and earned his M.D. from University of Wisconsin Medical School. Dr. Robertson was chosen as a Director because of his extensive experience as a physician and as an executive, board member and investor in companies across the healthcare industry.

Dr. Derace Schafferis a Director and a member of the Compensation Committee and the Nominating and Corporate Governance Committee, serving on the Board of Directors since March 2016. Dr. Schaffer is the founder and Chief Executive Officer of The Lan Group, a venture capital firm specializing in healthcare and high technology investments. He has also been a Clinical Professor of Radiology at both the University of Rochester Medical College as well as the Weill Cornell Medical College, and he currently serves as a Director of Altimmune, Inc. and as member of its Governance and Nominating Committee and Compensation Committee.College. Additionally, he serves as a member of the Board of Directors of private companies Medical Tracking Solutions, Inc., Partners Imaging, National Spine Centers LLC and Catalyst OrthoScience LLC. Previously, Dr. Schaffer served as Vice Chairman and Chief Executive Officer of Healthcare Acquisition Corp. from April 2005 to August 2007. He has served as Chairman of several healthcare companies, including Radiologix, Inc., of which he was the founder. Prior to that, he served as Chief Executive Officer and Chairman of Ide Imaging Group, P.C. from 1980 to 2001. Dr. Schaffer

more than two dozen companies, both public and private, over the past 30 years. Dr. Schaffer received his postgraduate radiology training at Harvard Medical School and Massachusetts General Hospital, where he served as Chief Resident, and is a member of the Alpha Omega Alpha Honor Medical Society. Dr. Schaffer was chosen as a Director because of his extensive experience as a radiologist and physician and as a serial entrepreneur, founder, executive, board member and investor in companies across the healthcare industry.

Dr. James H. Thrallis a Director and a member of the Nominating and Corporate Governance Committee, serving on the Board of Directors since February 2018. Dr. Thrall currently holds the Distinguished Juan M. Taveras Professorship of Radiology at Harvard Medical School, having also served as Chairman of the Department of Radiology at the Massachusetts General Hospital from 1988 until 2013. Previously, Dr. Thrall served as Chairman of Radiology at the Henry Ford Hospital between 1983 and 1988, where he also served as a Physician Trustee and held the position of Vice Chairman of the Board of Governors of the Henry Ford Medical Staff. Dr. Thrall is a member of the National Academy of Medicine and has served in leadership and board of directors positions at many U.S. and international medical and professional societies. Dr. Thrall received his M.D. from the University of Michigan in 1968 and trained in Radiology and Nuclear Medicine at the Walter Reed Army Medical Center, Washington, D.C. Dr. Thrall returned to the University of Michigan in 1975 and was promoted to Professor in 1981. Dr. Thrall was chosen as a Director because of his extensive experience in nuclear medicine and radiology, including in connection with imaging modalities and the development and use of innovative new technologies, including artificial intelligence.

Mary Anne Heino has served as our President and Chief Executive Officer and as a Director since August 2015. She previously served as our Chief Operating Officer, a position she held from March 2015 until August 2015, and as our Chief Commercial Officer, a position she held from April 2013 (when she joined the Company) until March 2015. Ms. Heino brings more than 2530 years of diverse pharmaceutical industry experience to the Board. Prior to joining Lantheus, Ms. Heino led Angelini Labopharm LLC and Labopharm USA in the roles of President and Senior Vice President of World Wide Sales and Marketing from February 2007 to March 2012. From May 2000 until February 2007, Ms. Heino served in numerous capacities at Centocor, Inc., a J&J company, including as Vice President, Strategic Planning and Competitive Intelligence, Vice President, Sales, Executive Director, Customer Relationship Management and Senior Director, Immunology Marketing. Ms. Heino began her professional career with Janssen Pharmaceutica as a Sales Representative in June 1989 and worked her way up to the role of Field Sales Director in 1999. Ms. Heino received her Master in Business Administration from the Stern School of Business at New York University. She earned a Bachelor of Science in Nursing from the City University of New York and a Bachelor of Science in Biology from the State University of New York at Stony Brook. Ms. Heino was chosen as a Director because of her role as President and Chief Executive Officer, which gives her an extensive understanding of our business and operations, and because of her strong commercial experience in the pharmaceutical industry.

John (Jack) W. CrowleyRobert J. Marshall, Jr. has servedjoined Lantheus as our Chief Financial Officer and Treasurer since March 2016.in September 2018. Mr. Crowley previously served as our interim Chief Financial Officer from December 2015Marshall brings to March 2016the Company more than 30 years of finance experience, including in mergers and as our Vice Presidentacquisitions, capital markets and Chief Accounting Officer from March 2015 to December 2015. Mr. Crowley held the position of Vice President, Finance from April 2013 until March 2015 and was Director, Accounting from September 2010 until April 2013.investor relations. Prior to joining Lantheus, Mr. CrowleyMarshall spent 16 years with Zimmer Biomet Holdings, Inc., a global medical device company with a leading position in musculoskeletal health. He held various senior leadership roles, including Vice President, Investor Relations and Corporate Treasurer, and most recently as Vice President, Americas Finance, for the U.S., Canadian and Latin American commercial markets. Prior to Zimmer Biomet, Mr. Marshall was the Assistant Corporate Controlleremployed with Brown & Williamson Tobacco, a subsidiary of Biogen Idec, the DirectorBritish American Tobacco, p.l.c., in Louisville, Kentucky, where he held several positions of Accounting at Thermo Fischer Scientific and a Senior Manager in the Audit practice of PricewaterhouseCoopers LLP.increasing responsibility. Mr. CrowleyMarshall holds a Master of Business Administration degreefrom Indiana University, South Bend, and a Bachelor of Business Administration in Finance from the University of MassachusettsNotre Dame. He also holds the CFA designation.

John Bollajoined Lantheus as Senior Vice President of Technical Operations in May 2018. In this role, he is responsible for leading the company’s supply chain, manufacturing, operations, engineering and facilities functions. He brings to the role more than 22 years of diverse supply chain, operations and manufacturing

experience in the pharmaceutical industry. Prior to joining Lantheus, Mr. Bolla spent 20 years at GlaxoSmithKline plc (“GSK”), a global branded pharmaceutical company. He held various senior leadership roles, including Vice President, Supply Chain, North America, where he was responsible for leading all manufacturing, supply planning, logistics and distribution for GSK’s largest global market. He also held senior roles as Vice President and Site General Manager for a large GSK manufacturing facility in the U.S., as well as Vice President and Global Head of External Supply and Global Contract Manufacturing. He has also served in multiple senior Procurement leadership roles at GSK. Mr. Bolla holds a Bachelor of Science in Business AdministrationAdministration/Accounting from Westfield StateThe University and is a Certified Public Accountant (Massachusetts licensure, current status inactive).of Central Florida.

Michael Duffy has served as our Senior Vice President, Law and Public Policy since 2018, as our Senior Vice President, Strategy and Business Development sincefrom October 2015 to 2018 and as our General Counsel and Secretary since January 2008. From 2002 to 2008, he served as Senior Vice President, General Counsel and Secretary of Point Therapeutics, Inc., a Boston-based biopharmaceutical company. Between 1999 and 2001, Mr. Duffy served as Senior Vice President, General Counsel and Secretary of

until 2007, Dr. Orlandi served, among other positions, as Vice President, Global Clinical Development of Otsuka Pharmaceuticals, a large Japanese pharmaceutical company. Earlier in his career, Dr. Orlandi served in increasing roles of clinical research responsibility at Medco Research, Inc. and the Radiopharmaceutical Division of The DuPont Merck Pharmaceutical Company, a predecessor organization to Lantheus, and The Upjohn Company. Dr. Orlandi received his medical degree from the University of Pavia Medical School in Pavia, Italy. He is currently an Adjunct Assistant Professor of Medicine at Tufts University School of Medicine in Boston, Massachusetts, and he is a founding member of the American Society of Nuclear Cardiology and a Fellow of the American College of Cardiology, the European Society of Cardiology and the American Society of Nuclear Cardiology. Dr. Orlandi is also servingserves as a member of the Board of Directors of the American Heart Association of Greater Boston.

Dr. Simon Robinson has served as our Senior Vice President, Research and Pharmaceutical Development since April 2018, having previously served as our Vice President, Research and Pharmaceutical Development since February 2010, and will serve as our Senior Vice President, Research and Pharmaceutical Development effective April 2018.2010. Dr. Robinson was our Senior Director, Discovery Research from 2008 to 2010 and our Director, Discovery Biology and Veterinary Sciences from 2001 to 2008. Prior to joining us, he held research positions at Bristol-Myers Squibb, Sphinx Pharmaceuticals, BASF and DuPont Pharmaceuticals. Dr. Robinson has more than 8090 publications and is listed as an inventor on 19more than 20 U.S. patents. He holds a Ph.D. and Bachelor of Science in Pharmacology from the University of Leeds, England and performed his post-doctoral training at the University of Wisconsin Clinical Cancer Center.

The current members of the Board of Directors and the committees of the Board, of Directors, each director’s class and the term of appointment are shown in the table below:

Board of Directors and Committee Meetings; Annual Meeting Attendance

In 2017,2018, the Board of Directors held nineseven meetings and acted by written consent in lieu of a meeting six times,one time, the Audit Committee held foursix meetings, the Compensation Committee held fivesix meetings and the Nominating and Corporate Governance Committee held foursix meetings. During 2017,2018, each director attended at least 75% of the total number of meetings held by the Board of Directors and those of its committees on which that director served. Thenon-employee directors of the Company regularly meet in executive session without management following adjournment of the meetings of the Board of Directors.Board. Under the Corporate Governance Guidelines and Principles adopted by the Board, of Directors, the independent ChairmanChairperson of the Board of Directors presides at those executive sessions, and those executive sessions must occur no less frequently than twice per year.

We have no formal policy with respect to director attendance at our Annual Meetings of Stockholders;Stockholders, however, we encourage all directors to attend. All but one of our then-serving directors attended the 20172018 Annual Meeting of Stockholders.

Board of Directors Leadership Structure and Over-Boarding Policy

Under our Corporate Governance Guidelines and Principles, the Board of Directors currently requires the separation of the offices of the Chairperson of the Board of Directors and the Company’s Chief Executive Officer. The Board of Directors periodically reviews its leadership structure and may make changes in the future.

Also under our Corporate Governance Guidelines and Principles, the Board of Directors currently prohibits a director from serving on more than five total public company boards (including our Board) and, if the director is the chief executive officer of a public company, then he or she may serve on no more than two other public company boards (other than his or her own).

Our written Corporate Governance Guidelines and Principles adopted by the Board of Directors are available in the Corporate Governance section of our Investor Relations website at http://investor.lantheus.com. The information on our website is not part of, and is not incorporated into, this proxy statement.

Board of Directors Role in Risk Oversight

The Company’s management is primarily responsible for theday-to-day management of the Company. However, the Board of Directors believes that oversight of risk management is one of its fundamental responsibilities. The Audit Committee is primarily responsible for oversight of the quality and integrity of the Company’s financial reporting process, internal controls over financial reporting and compliance programs. The Compensation Committee is responsible for reviewing compensation-related risks. The Nominating and Corporate Governance Committee is responsible for oversight of the Company’s corporate governance programs. The Financing and Strategy Committee is responsible for oversight of the Company’s capital structure and transactional-related risks. Management regularly reports to the Board of Directors and its committees on the risks that the Company may face and the steps that management is taking to mitigate those risks.

The Audit Committee is also responsible for reviewing and discussing with our management our policies and processes with respect to risk assessment and risk management. With respect to cybersecurity risks, the Company has made and continues to invest in new services and technologies and provides employee awareness training around phishing, malware and other cybersecurity risks, all in a manner reasonably intended to protect the Company to the greatest extent possible, against cybersecurity risks and security breaches.

Board of Directors candidates submitted by stockholders using substantially the same criteria it applies to recommendations from the Nominating and Corporate Governance Committee, directors and members of management. The stockholder making the recommendation must follow the procedures and provide the information set forth in our amended and restated bylaws.

Stockholders may submit recommendations by providing the person’s name and appropriate background and biographical information by writing to the attention of the Nominating and Corporate Governance Committee at Lantheus Holdings, Inc., 331 Treble Cove Road, North Billerica, MA 01862, Attention: Corporate Secretary. Stockholder nominations may be made at any time. However, in order for a candidate to be included in the slate of director nominees for approval by stockholders in connection with a meeting of stockholders and for information about the candidate to be included in the Company’s proxy materials for such a meeting, the stockholder must submit the information required by our amended and restated bylaws and other information reasonably requested by the Company within the timeframe described in our amended and restated bylaws under “Additional Information—Procedures for Submitting Stockholder Proposals.”

EXECUTIVE COMPENSATION

As an “emerging growth company,” as defined in the JOBS Act, we have elected to comply with the executive compensation disclosure rules applicable to “smaller reporting companies,” as defined in the Exchange Act. This section provides information on the compensation awarded to, earned by or paid to our principalchief executive officer, our chief financial officer, and our two other most highly-compensated executive officers, and our former chief financial officer, in each case, for the year ended December 31, 2017.2018. We refer to these individuals as our named executive officers. For 2017,2018, our named executive officers were:

Summary Compensation Table for Fiscal Years 2018 and 2017

The following table sets forth certain information with respect to compensation of our named executive officers for the years ended December 31, 20172018 and, 2016:if applicable, 2017:

We generally targetstarget the market fiftieth (50^th) percentile for each element of compensation, as presented by Pearl Meyer in theirits market analysis. Compensation recommendations were made to the Compensation Committeeanalysis based on adherence to this philosophy. Pearl Meyer received instruction directly from the Chairperson of the Compensation Committee.peer group and survey data described above. Our President and Chief Executive Officer assisted in developing, and presented to the Compensation Committee for its review and approval, management’s recommendations for our compensation program and specific awards tocompensation for her direct reports, including our other named executive direct reports.officers.

Base Salary

The base salaries of our named executive officers as of December 31, 20172018 are as follows:

For 2019, the corporate performance metrics will be weighted as follows: Net Revenue, 40%; Adjusted EPS, 30%; and Free Cash Flow, 30%. Failure to attain a threshold level of any of the corporate performance metrics will preclude any payout for the corresponding portion of the bonus payable under the 2019 Executive Bonus Plan. Attainment of each performance metric is calculated independently.

Cash LTIP

Our 2016 long-term incentive plan (“LTIP”) rewardsCash LTIP rewarded executive officers, including our named executive officers, for achieving certain specified, long-term financial, corporate and strategic performance goals, including certain annual revenue levels and certain operational goals. Achievement of performance goals under the Cash LTIP iswas measured as of September 1, 2017, and February 28, 2019, and cash payment iswas made after the Compensation Committee determinesdetermined whether and the extent to which the applicable performance goals were achieved.

In 2016, the Compensation Committee granted Cash LTIP awards to Ms. Heino, Mr. Crowley, Mr. Duffy, Dr. Orlandi and Mr. HealeyCrowley with targetmaximum cash amountspayouts of $900,000, $220,000, $220,000,$200,000 and $220,000, respectively.

As a result of the achievement of certain performance goals in accordance with their terms under the Cash LTIP prior to September 1, 2017, the Company paid $270,000, $66,000, $66,000,$60,000 and $66,000 to Ms. Heino, Mr. Crowley, Mr. Duffy, Dr. Orlandi and Mr. Healey,Crowley, respectively, in the third quarter of 2017. Payments associated withAs a result of the achievement of certain of the otherremaining performance goals in accordance with their terms under the Cash LTIP prior to February 28, 2019, will bethe Company paid $360,000, $88,000 and $80,000 to Ms. Heino, Mr. Duffy and Dr. Orlandi, respectively, in the first quarter of 2019. Because Mr. Marshall joined the Company in 2018, he did not participate in our Cash LTIP.

Long-Term Equity Incentive Awards

General

The Board of Directors approved and adopted our 2008 Equity Incentive Plan, our 2013 Equity Incentive Plan and our 2015 Equity Incentive Plan, each of which provides for grants of equity awards, including options to acquire Shares, RSAs, Restricted Stock Units (“RSUs”) subject to time-based vesting, PSAs and PSAs.RSUs subject to performance-based vesting (“PSUs”). Since its adoption in 2015, new grants of equity awards can only be made under the 2015 Equity Incentive Plan, which superseded theas it supersedes our previous plans.

Each ofAs described below, we have adopted Stock Ownership and Retention Guidelines that impose retention requirements on equity grants made in and after 2019 tonon-executive directors and executive officers, including our named executive officers, received a grant of RSAs and PSAs in 2017 commensurate withuntil that director or executive officer meets his or her rolerequired ownership stake.

Time-Based and in recognition of his or her performance during 2016. In February 2017, following consultation withPerformance-Based Annual Equity Awards

Based on the recommendations by its independent consultant, Pearl Meyer, theour Compensation Committee modified our equity compensation program andhas adopted guidelines regardingunder which the mix of time-based and performance-based equity to be granted to our named executive officers for 2017 (assuming, in the case of performance-based equity, achievement of performance goals at target levels). In accordance with these guidelines, in 2017 the Compensation Committee grantedCompany grants annual equity awards to executives, including our named executive officers, consisting of 50% PSAs, which vest based on attaining specified revenue and EBITDA goals over 2017, 2018 and 2019,time-based equity awards and 50% time-basedperformance-based equity awards (assuming target level achievement of applicable performance goals), with an aggregate grant date fair value determined commensurate with the executives’ roles and in recognition of their individual performance during the prior year. In 2018, Ms. Heino was granted 60,126 RSAs whichand 60,127 PSAs (at target), Mr. Duffy was granted 12,483 RSAs and 12,484 PSAs (at target), Dr. Orlandi was granted 12,814 RSAs and 12,815 PSAs (at target) and Mr. Crowley was granted 14,596 RSAs and 14,597 PSAs (at target). These annual RSAs vest in equal annual installments over three years, inon each case, subject to the named executive officer’s continued employment.One-sixth (1/6) of the total number of Shares subject to the PSAs may be earned based upon the achievement of specified revenue goals in each of 2017, 2018 and 2019, andone-sixth (1/6)first three anniversaries of the total numbergrant date, and these annual PSAs cliff vest on the third anniversary of Shares subjectthe grant date, in an amount equal to the PSAs may be earned based upon the achievement of specified EBITDA goals in each of 2017, 2018 and 2019.One-fourth (1/4)a percentage of the target number of Shares determined in reference to the extent to which the Company has achieved specified performance goals. Both RSAs and PSAs are also generally subject to the recipient remaining employed at the Company on the vesting date. We believe that the cliff vesting of the PSAs also serves as a meaningful retention tool. This mix of time and performance-based equity incentives is

intended to keep us highly-competitive within the executive talent market, while ensuring executives are focused on longer-term organizational performance. In connection with his hire in September 2018, Mr. Marshall was granted 44,642 RSAs, which vest in equal installments on each of the first four anniversaries of the grant date, generally subject to his continued employment with the Company on the applicable vesting date.

In February 2018, in consultation with Pearl Meyer and based on its review of peer group of public companies and other survey data described above, the Compensation Committee changed the performance-based goals used in equity award grants, from revenue and EBITDA, to relative Total Shareholder Return (“rTSR”) of the Company’s common stock, as compared to other companies in the S&P SmallCap Healthcare Index over a three full calendar year performance period, starting with the calendar year in which the grant was made. The adoption of rTSR was intended to ensure management alignment and accountability towards long term shareholder value creation. The Compensation Committee utilized the same equity grant approach in 2019.

The Compensation Committee granted executives rTSR PSAs as part of their annual equity grants in 2018 and rTSR PSUs as part of their annual equity grants in 2019, with each award giving the recipient the right to earn or receive one share of common stock of the Company with respect to each rTSR PSA or PSU (as applicable) awarded, generally subject to the holder’s continued employment with the Company on the vesting date. The relative changes in share prices during the performance period will be earned ifmeasured using the thresholdaverage closing prices during the 30 days preceding the beginning and the end of the performance level is achieved,one-half (1/2)period. The percentage of the target number of Shares that can vest under the rTSR PSAs and rTSR PSUs, will earned ifbe as follows:

In the targetevent that the Company’s rTSR percentile rank for the performance level is achieved and one hundred twenty percentperiod falls between any of the target number of Sharesthresholds set forth above (to the extent greater than the threshold and lower than the maximum), the vesting percentage will be earned if the maximum performance level is achieved, with

Clawback Policy Under 2015 Equity Incentive Plan

Under our 2015 Equity Incentive Plan, if a participant receives compensation pursuant to an award calculated by reference to financial statements that are subsequently required to be restated in a way that would decrease the value of suchthat compensation, the participant will, upon our written request, forfeit and repay to us the difference between what the participant received and what the participant should have received based on the restated accounting, restatement, in accordance with (i) our compensation recovery, “clawback” or similar policy, as may be in effect from time to time, and (ii) any compensation recovery, “clawback” or similar policy made applicable by law, including the Dodd-Frank Act.

Other Benefits

Retirement Plans

We offer a 401(k) qualified defined contribution retirement plan in which our employees, including our named executive officers, are eligible to participate, with a 75% employer match of each participant’s contributions up to 6% of the participant’s eligible compensation. We do not offer any other qualified ornon-qualified retirement plans.

Other Benefits

Except as otherwise discussed herein, otherOur welfare and employee-benefit programs are the same for all of our eligible employees, including our named executive officers, and our named executive officers do not receive additional benefits outside of those offered to our other employees.

Nonqualified Deferred Compensation

We do not offer our executives or other employees any nonqualified deferred compensation.

Outstanding Equity Awards at December 31, 20172018

The following tables include certain information with respect to equity awards held by our named executive officers as of December 31, 2017:2018, based on a closing stock price of $15.65 on that date:

The table below quantifies the amounts that would have become payable under each named executive officer’s employment agreement and equity award agreements if, on December 31, 2017,2018, a change of control werehad been consummated and the named executive officer’s employment was terminated without cause or the named executive resigned for good reason.reason under the agreements in place on January 25, 2019, as described above. Due to the number of factors that affect the nature and amount of any benefits provided upon the events discussed above, any actual amounts paid may be different. Factors that could affect these amounts include the timing during the year of any such event, the cost of benefits, and the named executive officer’s base salary.salary and our stock price.

No compensation is payabledue to our named executive officers upon a termination of employment or upon a change of control that is not followed by a qualifying termination of employment, other than in the as described above or as required by applicable law.

In addition, each of the employment agreementsseverance arrangements with our named executive officers provides for a modifiedcut-back in the event that adverse tax consequences are imposed on the receipt of parachute payments by the named executive officer pursuant to Sections 280G and 4999 of the Internal Revenue Code of 1986, as amended (the “Code”). If any payments or benefits from the Company in the nature of compensation that are paid to or for the named executive officer’s benefit, whether paid or payable pursuant to his or her employment agreement or otherwise (each, a “Payment”), would subject the named executive officer to the excise tax under Section 4999 of the Code, then the Payments will be reduced to the greatest amount of the Payments that can be paid that would not result in the imposition of the excise tax (the “Reduced Amount”). However, if the amount of the Payments the named executive officer would receive after payment of all applicable taxes, including any excise taxes, is greater than the Reduced Amount, then no such reduction will occur.

Separation Agreement with Mr. Crowley

In connection with his separation from the Company in September 2018, Mr. Crowley entered into a separation agreement with the Company under which Mr. Crowley received (i) a cash severance payment of $656,550, representing his annual base salary, target annual bonus and the portion of his cash long-term incentive plan award that had been achieved, (ii) reimbursement for COBRA premiums and up to $25,000 of outplacement benefits for up to twelve months following his separation date, and (iii) accelerated vesting of 40,838 unvested RSAs, subject to transfer restrictions through the original vesting dates of such awards or an earlier change in control, in addition to any amounts required by law or the terms of the Company’s policies and benefit plans. The separation agreement included a confirmation of the restrictive covenants to which Mr. Crowley was subject, includingconfidentiality, non-competition, non-solicitation, no-hire and invention assignment covenants, and a release of claims in favor of the Company, its affiliates and certain other persons.

Stock Ownership and Retention Guidelines

In February 2019, the Compensation Committee recommended, and the Board approved and adopted, Stock Ownership and Retention Guidelines (“Guidelines”). Under these Guidelines:

Until a director or executive officer achieves his or her required ownership level, he or she is required to retain 50% of allafter-tax Shares issued upon (i) exercise of any vested Company stock option award (calculated on a net exercise basis) or (ii) the vesting of any other Company stock incentive award (such as the RSAs, RSUs, PSAs and PSUs described above). These retention requirements apply to new equity award grants commencing in 2019.

Our executive officers andnon-employee directors are required to comply with the Guidelines within five years of when the Guidelines apply to them. As of February 26, 2019, Messrs. Markison, Clemmer and Leno, Ms. McHugh and Drs. Robertson and Schaffer, and Ms. Heino and Mr. Duffy each had already achieved the requirements under the stock ownership guidelines.

A copy of our Stock Ownership and Retention Guidelines is available on the Corporate Governance section of our Investor Relations website at http://investor.lantheus.com.

DIRECTOR COMPENSATION

For 2017,2018, each of ournon-employee directors was eligible to receive the following annual compensation in cash (which is paid quarterly in advance and prorated for partial periods of service) for services as a director and, as applicable, Board committee member:

In 2016, we did not compensate our

The Compensation Committee periodically engages Pearl Meyer to review the Company’s outside director compensation program. The review covers the levels of cash and equity retainers that are provided to outside directors, or committee members with per meeting fees. For 2017, afteras well as the overall structure of the program, against the same peer group of public companies used for executive compensation benchmarking purposes. The independent consultant makes recommendations to the Compensation Committee for consideration, and the Compensation Committee subsequently recommends any changes to the outside director compensation program for the Board’s approval. After reviewing the results of a compensation study prepared by Pearl Meyer, the Compensation Committee increased the additional annual fee for the Chairperson ofrecommended, and the Board of Directorsapproved, an increase to $50,000 and reduced the annual fee for each member of the Nominating and Governance Committee to $4,000. For 2017, former directors Messrs. Burgstahler and Venkataraman waived their right to receive any compensation or equity in respect of their service as directors and committee members. $5,000 for 2019.

Directors who are employees of the Company do not receive separate or additional compensation for their services as directors or committee members. On April 27, 2017, Mr. Venkataraman did not stand for election to the Board and, on September 7, 2017, Mr. Burgstahler resigned from the Board. Neither resignation was due to a disagreement with the Company, the Board or management on any matter relating to the Company’s operations, policies or practices.

On January 25, 2017, Ms. McHugh was appointed to the Board of Directors. She was granted 2,671 RSAs upon her appointment, which vested in full on January 25, 2018.

On February 27, 2017,In 2018, each person then-serving as anon-employee director (with the exception of Messrs. Burgstahler and Venkataraman, who waived their compensation as directors and committee members in 2017) was granted 8,7307,911 RSAs under our 2015 Equity Incentive Plan. These 20172018 awards vested in full on March 5, 2019. On February 27, 2018.26, 2019, eachnon-employee director was granted 5,353 RSUs under our 2015 Equity Incentive Plan. These 2019 annual equity awards will vest in full on February 26, 2020, generally subject to continued service through that date.

All directors are subject to the Company’s Stock Ownership and Retention Guidelines described above.

Non-employee members of the Board of Directorsdirectors are also entitled to reimbursement forout-of-pocket expenses incurred in connection with rendering suchthose services for so long as they serve as directors.

The following table shows compensation paid to the individuals who served as ournon-employee directors in 2017:2018:

STOCK OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

The following table sets forth information regarding the beneficial ownership of our common stock held by (i) each of our directors, (ii) each of our named executive officers, (iii) our directors and named executive officers as a group and (iv) each person known to us to beneficially own more than 5% of our common stock. For our directors and officers, the information is as of the Record Date, February 22, 2018.26, 2019. For other stockholders who own more than 5% of our common stock, the information is as of the most recent Schedule 13G filed by each such stockholderof those stockholders with the SEC.

Beneficial ownership of Shares is determined under rules of the SEC and generally includes any Shares over which a person exercises sole or shared voting or investment power. Except as noted by footnote, and subject to community property laws where applicable, we believe based on the information provided to us that the persons and entities named in the table below have sole voting and investment power with respect to all Shares shown as beneficially owned by them.

Percentage of beneficial ownership is calculated in part based on 37,860,711 shares38,628,501 Shares outstanding as of February 22, 2018.26, 2019. Shares subject to RSAs that are currently vested or that will vest within 60 days of the date of this proxy statement, and stock options currently exercisable or exercisable within 60 days of the date of this proxy statement, are deemed to be outstanding and beneficially owned by the person holding those RSAs and options for the purposes of computing the percentage of beneficial ownership of that person and any group of which that person is a member, but are not deemed outstanding for the purpose of computing the percentage of beneficial ownership for any other person.

Unless otherwise indicated, the address for each holder listed below is c/o Lantheus Holdings, Inc., 331 Treble Cove Road, North Billerica, MA 01862.

SECTION 16(a) BENEFICIAL OWNERSHIP REPORTING COMPLIANCE

Section 16(a) of the Exchange Act requires the Company’s directors, certain executive officers and persons who beneficially own more than 10% of the Company’s Shares, to file reports of beneficial ownership and reports of changes in beneficial ownership with the SEC. These persons are required by SEC regulations to furnish the Company with copies of all Section 16(a) reports that they file. We assist our directors and executive officers with their Section 16(a) filings. Based solely on a review of reports filed with the SEC and written representations from directors and executive officers, we believe that all required reports under Section 16(a) with respect to those persons were timely filed during 2017.2018.

CERTAIN RELATIONSHIPS AND RELATED PERSON TRANSACTIONS

This section describes certain relationships and related person transactions between us or our subsidiaries, on the one hand, and our directors, director nominees, executive officers, holders of more than 5% of our voting securities and certain related persons of any of the foregoing, on the other hand, since January 1, 2017.2018.

Shareholders Agreements

In connection with Avista’s original acquisition of the Company’s business (the “Acquisition”), the Company entered into (i) a Shareholders Agreement with Avista and certain Management Shareholders, dated January 8, 2008 and subsequently amended on February 26, 2008 and on June 25, 2015 in connection with the consummation of our initial public offering (the “Initial Shareholders Agreement”), and (ii) an Employee Shareholders Agreement with Avista and certain employee stockholders named therein, dated as of May 30, 2008 and subsequently amended on June 25, 2015 in connection with the consummation of our initial public offering (the “Employee Shareholders Agreement,” and, collectively with the Initial Shareholders Agreement, the “Shareholders Agreements”). Messrs. Markison and Leno were Management Shareholders parties to the Initial Shareholders Agreement, and certain of our executive officers were parties to the Employee Shareholders Agreement.

Until they terminated in accordance with their respective terms in 2017, the Shareholders Agreements governed the parties’ respective rights, duties and obligations with respect to the ownership of Company securities. The Initial Shareholders Agreement provided demand registration rights in favor of Avista and piggy-back registration rights in favor of Avista and the Management Shareholders. The Initial Shareholders Agreement also provided Avista with the right to nominate two directors to the Board of Directors for so long as it owns 25% or more of our issued and outstanding Shares, and the right to nominate one director for election to the Board of Directors for so long as it beneficially owns 10% or more, but less than 25%, of our issued and outstanding Shares.

Prior to June 30, 2016, the first anniversary of our initial public offering, both Shareholders Agreements (i) provided the Company with the right to repurchase shares held by Management Shareholders or employee stockholders who ceased to be employed by the Company or any of its subsidiaries and (ii) restricted the ability of the Management Shareholders and employee stockholders to transfer Shares that they owned, allowing Management Shareholders and employee stockholders to transfer Shares only in proportion to the transfer of Shares by Avista. Those restrictions expired on June 30, 2016.

INC Research Master Services Agreement

In the first quarter of 2016, we entered into a services agreement with INC Research Holdings, Inc. (“INC”), now known as Syneos Health, Inc., to provide pharmacovigilance services. Avista and certain of its affiliates were principal owners of both us and INC during 2016. The agreement has a term of three years. During the year ended December 31, 2016, investment funds affiliated with Avista disposed of shares of INC common stock held by them. As a result, such investment funds were no longer a principal owner of INC. Related party expenses included in the following table represent expenses incurred during the period under which investment funds affiliated with Avista held an investment in INC.

VWR Scientific Purchases

We purchase inventory supplies from VWR Scientific (“VWR”). Avista and certain of its affiliates were principal owners of both us and VWR during 2017 and 2016.

Indemnification Agreements

We have entered into indemnification agreements with each of our directors and executive officers. These agreements, among other things, require us to indemnify each director and executive officer to the fullest extent

AMENDMENTS TO OUR AMENDED AND RESTATED CERTIFICATE OF INCORPORATIONPROPOSAL 2:

(PROPOSALS 2 THROUGH 4)

The Board has unanimously approved, and recommendsAmendment to the stockholders that they adopt, amendments to our amended and restated certificate of incorporation (our “Charter”) to:

Background: In General

Since we completed our initial public offering (“IPO”), there have been many changes to our stockholder base. Specifically, when we completed our IPO, Avista Capital Partners, LP, Avista Capital Partners (Offshore) LP and ACP LanternCo-Invest LLC (collectively referred to as “Avista”) collectively owned more than 64% of the outstanding shares of our common stock. At the time of our IPO, there were numerous items in our Charter that reflected those ownership positions.

As of August 14, 2017, Avista no longer beneficially owned any shares of our common stock. Therefore, we have reviewed our Charter to determine what revisions are advisable due to these changes in our stockholder base. During this review, we also analyzed recent corporate governance trends and considered what other changes are advisable.

Separate Proposals

Although each of these proposals have come about based on our review of our Charter due to changes in our stockholder base and our review of recent corporate governance trends, we are submitting these amendments to the stockholders as separate proposals so that our stockholders are able to express their views on each amendment separately. Each proposal is not conditioned on the approval of any other proposal. Our Charter provides generally that the affirmative vote of the majority of the shares entitled to vote on any matter is required to amend our Charter, but, in certain instances, the affirmative vote of 66 2/3% of the shares entitled to vote is required to amend our Charter. Therefore, we will amend our Charter to implement:

Corresponding Changes to our Bylaws

As part of our review of our Charter and corporate governance trends, we also reviewed our amended and restated bylaws and identified the corresponding provisions of our bylaws that would be revised assuming the proposals in this proxy statement are approved by our stockholders. Even though our Board has the right to amend our bylaws without the need to seek stockholder approval, our Board has determined that, to the extent that our stockholders do not approve a Charter proposal that has a corresponding change in our amended and restated bylaws, the Board will not make that change in our amended and restated bylaws. The changes proposed to be made to our amended and restated bylaws are as follows:

Reasons for Voting for the Proposal

Long-Term Equity is a Key Component of our Compensation Objective

Our Company is Committed to the Effective Utilization of Shares

Our 2015 Equity Incentive Plan is consistent with principles of good corporate governance

The Board believes that the 2015 Equity Incentive Plan will promote the interests of stockholders and is consistent with principles of good corporate governance, including:

The 2015 Equity Incentive Plan Requires Additional Shares to Meet our Forecasted Needs

We expect to grant equity awards representing approximately 631,000 Shares during 2019 (representing approximately 1.6% of our outstanding Shares as of March 1, 2019). We anticipate limited forfeitures and cancellations under the 2015 Equity Incentive Plan, consistent with our previous history. Forfeitures of awards under our previous equity plans cannot be credited to replenish the Shares available for grant under the 2015 Equity Plan.

As a result, the Board, based on the recommendation of the Compensation Committee, concluded that increasing the number of Shares available for issuance under our 2015 Equity Incentive Plan would provide the Company with the ability to undertake the flexible and balanced approach of using equity and cash compensation as needed to help us retain and motivate employees, which furthers stockholder interests.

Summary of the 2015 Equity Incentive Plan

The following is a summary of the material features of the 2015 Equity Incentive Plan. The summary is qualified in its entirety by the 2015 Equity Incentive Plan as set forth in Appendix A.

Administration

The 2015 Equity Incentive Plan is administered by the Compensation Committee or another committee of the Board, comprised of no fewer than two members of the Board who are appointed by the Board to administer the plan, or, subject to the limitations set forth in the 2015 Equity Incentive Plan, the Board (the appropriate body is referred to as the “Committee”). Subject to the limitations set forth in the 2015 Equity Incentive Plan, the Committee has the authority to determine the persons to whom awards are to be granted, prescribe the restrictions, terms and conditions of all awards, interpret the 2015 Equity Incentive Plan and adoptsub-plans and rules for the administration, interpretation and application of the 2015 Equity Incentive Plan.