UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): June 19, 2020

Progenics Pharmaceuticals, Inc.

(Exact Name of Registrant as Specified in Charter)

One World Trade Center, 47th Floor, New York, New York 10007

(Address of Principal Executive Offices)                (Zip Code)

Registrant’s telephone number, including area code: (646) 975-2500

Not Applicable

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2).

Emerging growth company  ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Introductory Note

This Current Report on Form 8-K is being filed in connection with the consummation, on June 19, 2020 (the “Closing Date”), of the previously announced acquisition of Progenics Pharmaceuticals, Inc. (“Progenics”) pursuant to the Amended and Restated Agreement and Plan of Merger, dated as of February 20, 2020 (the “Merger Agreement”), by and among Progenics, Lantheus Holdings, Inc. (“Lantheus”) and Plato Merger Sub, Inc., a wholly owned subsidiary of Lantheus Holdings (“Merger Sub”), pursuant to which Merger Sub merged with and into Progenics (the “Merger”), with Progenics surviving the Merger as a wholly-owned subsidiary of Lantheus.

Item 2.01. Completion of Acquisition or Disposal of Assets.

On the Closing Date, Lantheus and Progenics completed the Merger. At the effective time of the Merger (the “Effective Time”), each share of Progenics’ common stock, par value $0.0013 per share (“Common Stock”), issued and outstanding immediately prior to the Effective Time (other than certain excluded shares as described in the Merger Agreement) were automatically converted into the right to receive (i) 0.31 of a share of Lantheus common stock and (ii) one non-transferable contingent value right (a “CVR”) representing the right to receive up to two contingent payments upon the achievement of certain milestones at the times and subject to the terms of the Contingent Value Rights Agreement (the “CVR Agreement”), dated as of June 19, 2020, by and between Lantheus and Computershare, Inc., a Delaware corporation, and its wholly owned subsidiary, Computershare Trust Company, N.A., a federally chartered trust company, collectively, as rights agent (both clause (i) and (ii) being the “Merger Consideration”).

At the Effective Time, in accordance with the Merger Agreement, each Progenics stock option with a per share exercise price that does not exceed $4.42 (an “in-the-money option”) and each Progenics stock option with a per share exercise price that does exceed $4.42 (an “out-of-the-money option”) was treated as follows:

The aggregate number of shares of Lantheus common stock expected to be issued in connection with the Merger is 26,844,957. In addition, in connection with the Merger, Lantheus expects to assume 34,000 in-the-money options and 6,507,342 out-of-the-money options, each to be converted into Lantheus stock options at the exchange ratio noted above. The aggregate number of CVRs expected to be issued in connection with the Merger is 86,630,634.    

The foregoing summary of the Merger Agreement and the transactions contemplated thereby does not purport to be complete and is subject to, and qualified in its entirety by, the full text of the Merger Agreement, which is incorporated by reference as Exhibit 2.1 hereto and is incorporated in this Item 2.01 by reference.

Item 3.01. Notice of Delisting or Failure to Satisfy a Continued Listing Rule or Standard; Transfer of Listing.

On the Closing Date, in connection with the completion of the Merger, Progenics notified The Nasdaq Stock Market (“Nasdaq”) that the Merger had been completed and requested that trading of the Common Stock on Nasdaq be suspended prior to the opening of trading on June 22, 2020. In addition, Progenics requested that Nasdaq file with the Securities and Exchange Commission (the “SEC”) a Notification of Removal from Listing and/or Registration on Form 25 to delist the Common Stock from Nasdaq and deregister the Common Stock under Section 12(b) of the Securities and Exchange Act of 1934, as amended (the “Exchange Act”), on June 22, 2020. As a result, the Common Stock will no longer be listed on Nasdaq. In addition, Progenics intends to file with the SEC a certification on Form 15 under the Exchange Act to terminate the registration of all Progenics securities registered under Section 12(g) of the Exchange Act and to suspend Progenics’ reporting obligations under Sections 13 and 15(d) of the Exchange Act.

The information set forth in the Introductory Note and Item 2.01 of this report is incorporated in this Item 3.01 by reference.

Item 3.03. Material Modification to Rights of Security Holders.

The information set forth in the Introductory Note and Items 2.01, 3.01, and 5.03 is incorporated in this Item 3.03 by reference.

On the Closing Date, each holder of Common Stock issued and outstanding immediately prior to the Effective Time ceased to have any rights as a stockholder of Progenics, other than (except for certain excluded shares as described in the Merger Agreement) the right to receive the per share Merger Consideration pursuant to the terms of the Merger Agreement.

Item 5.01. Changes in Control of Registrant.

On the Closing Date, a change in control of Progenics occurred and Progenics became a wholly owned subsidiary of Lantheus.

The information set forth in the Introductory Note and Item 3.03 and 5.02 is incorporated in this Item 5.01 by reference.

Item 5.02. Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On the Closing Date, Ann MacDougall, Gérard Ber, Bradley Campbell, Eric Ende, Karen Jean Ferrante, David Mims, and Heinz Mäusli resigned from their respective roles as directors on the board of directors of Progenics. Effective as of the Effective Time, Mary Anne Heino, Robert J. Marshall Jr. and Michael P. Duffy, the directors of Merger Sub, were appointed as directors to the board of directors of Progenics.

In addition, on the Closing Date, David Mims resigned as Interim Chief Executive Officer and Interim Chief Financial Officer of Progenics. In addition, effective as of the Effective Time, Mary Anne Heino was appointed as Chief Executive Officer and President and Robert J. Marshall Jr. was appointed as Chief Financial Officer and Treasurer.

Item 5.03. Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year.

On the Closing Date, Progenics’ certificate of incorporation was amended and restated in its entirety to be in the form attached hereto as Exhibit 3.1.

On the Closing Date, Progenics’ bylaws were amended and restated in their entirety to be in the form attached hereto as Exhibit 3.2.

The information set forth in Item 2.01 of this report is incorporated in this Item 5.03 by reference.

Item 8.01. Other Events.

On June 22, 2020, Progenics and Lantheus issued a joint press release announcing the consummation of the Merger. A copy of the joint press release is filed as Exhibit 99.1 to this Form 8-K and is incorporated herein by reference.

(d) Exhibits.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date: June 22, 2020

Exhibit 3.1

FOURTH AMENDED AND RESTATED

CERTIFICATE OF INCORPORATION

OF

PROGENICS PHARMACEUTICALS, INC.

FIRST: The name of the Corporation (the “Corporation”) is

Progenics Pharmaceuticals, Inc.

SECOND: The registered office of the Corporation in the State of Delaware is located at 251 Little Falls Drive, Wilmington, DE 19808, and County of New Castle. The name of its registered agent in the State of Delaware at such address is Corporation Service Company.

THIRD: The purpose of the Corporation is to engage, directly or indirectly, in any lawful act or activity for which corporations may be organized under the General Corporation Law of the State of Delaware (the “DGCL”).

FOURTH: The total authorized capital stock of the Corporation shall be 1,000 shares of common stock, $0.01 par value per share.

FIFTH: The Corporation is to have perpetual existence.

SIXTH: The business of the Corporation shall be managed under the direction of the Board of Directors of the Corporation (the “Board of Directors”) except as otherwise provided by applicable law. The number of directors of the Corporation shall be fixed from time to time by, or in the manner provided in, the By-Laws of the Corporation (the “By-Laws”). Election of directors need not be by written ballot unless the By-Laws shall so provide.

SEVENTH: The Board of Directors may make, alter or repeal the By-Laws except as otherwise provided in the By-Laws adopted by the Corporation’s stockholders.

EIGHTH: The personal liability of the directors of the Corporation is hereby eliminated to the fullest extent permitted by paragraph (7) of subsection (b) of §102 of the General Corporation Law of the State of Delaware, as the same may be amended and supplemented.

NINTH: The Corporation shall, to the fullest extent permitted by Section 145 of the General Corporation Law of the State of Delaware, as amended from time to time, indemnify all persons whom it may indemnify pursuant thereto.

TENTH: The Corporation reserves the right to amend, alter, change or repeal any provision contained in this Certificate of Incorporation in the manner now or hereafter prescribed by statute, and all rights conferred herein upon the Corporation’s stockholders, directors and officers are granted subject to this reservation.

Exhibit 3.2

PROGENICS PHARMACEUTICALS, INC.

(THE “CORPORATION”)

BY-LAWS

(AMENDED AND RESTATED AS OF JUNE 19, 2020)

ARTICLE I

Meetings of Stockholders

Section 1.1 Annual Meetings. The annual meeting of the stockholders for the election of directors and for the transaction of such other business as properly may come before such meeting shall be held each year on such date, and at such time and place within or without the State of Delaware, as may be designated by the Board of Directors.

Section 1.2 Special Meetings. Special meetings of the stockholders for any proper purpose or purposes may be called at any time by the Board of Directors to be held on such date, and at such time and place within or without the State of Delaware, as the Board of Directors shall direct. A special meeting of the stockholders shall be called by the president or the secretary of the Corporation whenever stockholders owning a majority of the shares of the Corporation then issued and outstanding and entitled to vote on matters to be submitted to stockholders of the Corporation shall make application therefor in writing. Any such written request shall state a proper purpose or purposes of the meeting and shall be delivered to the president or the secretary of the Corporation.

Section 1.3 Notice of Meetings. Written notice, signed by the president, the secretary or any assistant secretary of the Corporation, of every meeting of stockholders stating the date and time when, and the place where, such meeting is to be held, shall be delivered either personally or by mail to each stockholder entitled to vote at such meeting

not less than ten (10) nor more than sixty (60) days before the date of such meeting, except as otherwise provided by law. The purpose or purposes for which such meeting is called may, in the case of an annual meeting, and shall in the case of a special meeting, also be stated in such notice. If mailed, such notice shall be directed to a stockholder at such stockholder’s address as it shall appear on the stock books of the Corporation, unless such stockholder shall have filed with the president or secretary of the Corporation a written request that notices intended for such stockholder be mailed to some other address, in which case it shall be mailed to the address designated in such request. Whenever any notice is required to be given under the provisions of the General Corporation Law of the State of Delaware, the Certificate of Incorporation or these By-Laws, a waiver thereof, signed by the stockholder entitled to such notice, whether before or after the time stated therein, shall be deemed equivalent thereto. Attendance of a stockholder at the meeting shall be deemed equivalent to a written waiver of notice of such meeting.

Section 1.4 Quorum. The presence at any meeting of stockholders, in person or by proxy, of the holders of record of a majority of the shares then issued and outstanding and entitled to vote shall be necessary and sufficient to constitute a quorum for the transaction of business, except as otherwise provided by law.

Section 1.5 Adjournments. In the absence of a quorum, the stockholders so present by a majority in voting power thereof, or, if no stockholder entitled to vote is present in person or by proxy, any officer entitled to preside at or act as secretary of a meeting of stockholders, may adjourn such meeting from time to time until a quorum shall be present.

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Section 1.6 Voting. Directors shall be chosen by a plurality of the votes cast at the election, and, except as otherwise provided by law or by the Certificate of Incorporation, all other questions shall be determined by a majority of the votes cast on such question.

Section 1.7 Proxies. Any stockholder entitled to vote may vote by proxy, provided that the instrument authorizing such proxy to act shall have been executed in writing (which shall include telegraphing or cabling) by the stockholder himself or herself or by such stockholder’s duly authorized attorney.

Section 1.8 Judges of Election. The Board of Directors may appoint judges of election to serve at any election of directors and at balloting on any other matter that may properly come before a meeting of stockholders. If no such appointment shall be made, or if any of the judges so appointed shall fail to attend, or refuse or be unable to serve, then such appointment may be made by the presiding officer at the meeting.

ARTICLE II

Board of Directors

Section 2.1 Number. The number of directors which shall constitute the whole Board of Directors shall be fixed from time to time by resolution of the Board of Directors or stockholders (any such resolution of either the Board of Directors or stockholders being subject to any later resolution of either of them). The first Board of Directors and subsequent Boards of Directors shall consist of three (3) directors until changed as herein provided.

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Section 2.2 Election and Term of Office. Directors shall be elected at the annual meeting of the stockholders, except as provided in Section 2.3. Each director (whether elected at an annual meeting or to fill a vacancy or otherwise) shall continue in office until such Director’s successor shall have been elected and qualified or until such Director’s earlier death, resignation or removal in the manner hereinafter provided.

Section 2.3 Vacancies and Additional Directorships. If any vacancy shall occur among the directors by reason of death, resignation or removal, or as the result of an increase in the number of directorships, a majority of the directors then in office, or a sole remaining director, though less than a quorum, may fill any such vacancy.

Section 2.4 Regular Meetings. Regular meetings of the Board of Directors may be held at such places within or without the State of Delaware and at such times as the Board of Directors may from time to time determine.

Section 2.5 Special Meetings. Special meetings of the Board of Directors may be held at any time or place within or without the State of Delaware whenever called by the president, any vice president, the secretary, or by any member of the Board of Directors. Notice of a special meeting of the Board of Directors shall be given by the person or persons calling the meeting at least twenty-four hours before the special meeting.

Section 2.6 Waiver of Notice. Whenever any notice is required to be given under the provisions of the General Corporation Law of the State of Delaware, the Certificate of Incorporation or these By-Laws, a waiver thereof, signed by the director entitled to such notice, whether before or after the time stated therein, shall be deemed equivalent thereto. Attendance of a director at a meeting shall be deemed equivalent to a written waiver of notice of such meeting.

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Section 2.7 Quorum. At each meeting of the Board of Directors, the presence of a majority of the total number of members of the Board of Directors as constituted from time to time shall be necessary and sufficient to constitute a quorum for the transaction of business, except that when the Board of Directors consists of one or two directors, then the one or two directors, respectively, shall constitute a quorum. In the absence of a quorum, a majority of those present at the time and place of any meeting may adjourn the meeting from time to time until a quorum shall be present and the meeting may be held as so adjourned without further notice or waiver. A majority of those present at any meeting at which a quorum is present may decide any question brought before such meeting, except as otherwise provided by law, the Certificate of Incorporation or these By-Laws.

Section 2.8 Telephonic Meetings. Unless otherwise restricted by the Certificate of Incorporation or these By-Laws, members of the Board of D irectors, or any committee designated by the Board of Directors, may participate in a meeting of the Board of Directors, or such committee, as the case may be, by means of conference telephone or similar communications equipment by means of which all persons participating in the meeting can hear each other, and such participation in a meeting shall constitute presence in person at the meeting.

Section 2.9 Resignation of Directors. Any director may resign at any time by giving written notice of such resignation to the Board of Directors. Unless otherwise specified in such notice, such resignation shall take effect upon receipt thereof by the Board of Directors or any such officer, and the acceptance of such resignation shall not be necessary to make it effective.

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Section 2.10 Removal of Directors. At any special meeting of the stockholders, duly called as provided in these By-Laws, any director or directors may be removed from office, either with or without cause, as provided by law. At such meeting a successor or successors may be elected by a plurality of the votes cast, or if any such vacancy is not so filled, it may be filled by the directors as provided in Section 2.3.

Section 2.11 Compensation of Directors. Directors shall receive such reasonable compensation for their services whether in the form of salary or a fixed fee for attendance at meetings, with expenses, if any, as the Board of Directors may from time to time determine. Nothing herein contained shall be construed to preclude any director from serving the Corporation in any other capacity and receiving compensation therefor.

Section 2.12 General Powers. The Board of Directors shall have all powers necessary or appropriate for the management of the business and affairs of the Corporation, and, in addition to the power and authority conferred by these By-Laws, may exercise all powers of the Corporation and do all such lawful acts and things as are not by statute, these By-Laws or the Certificate of Incorporation directed or required to be exercised or done by the stockholders.

Notwithstanding anything in these By-Laws to the contrary, except to the extent prohibited by law, the Board of Directors shall have the right (which, to the extent exercised, shall be exclusive) to establish the rights, powers, duties, rules and procedures that from time to time shall govern the Board of Directors and each of its members, including, without limitation, the vote required for any action by the Board of Directors, and that from time to time shall affect the Directors’ power to manage the business and affairs of the Company; and no By-Law shall be adopted by stockholders which shall impair or impede the implementation of the foregoing.

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ARTICLE III

Committees of the Board

Section 3.1 Committees. The Board of Directors may designate one or more committees, each committee to consist of one or more of the directors of the Corporation. The Board of Directors may designate one or more directors as alternate members of any committee, who may replace any absent or disqualified member at any meeting of the committee. In the absence or disqualification of a member of the committee, the member or members thereof present at any meeting and not disqualified from voting, whether or not he, she or they constitute a quorum, may unanimously appoint another member of the Board of Directors to act at the meeting in place of any such absent or disqualified member. Any such committee, to the extent permitted by law and to the extent provided in any resolution of the Board of Directors, shall have and may exercise all the powers and authority of the Board of Directors in the management of the business and affairs of the Corporation, and may authorize the seal of the Corporation to be affixed to all papers which may require it.

Section 3.2 Committee Rules. Unless the Board of Directors otherwise provides, each committee designated by the Board of Directors may make, alter and repeal rules for the conduct of its business. In the absence of such rules each committee shall conduct its business in the same manner as the Board of Directors conducts its business pursuant to Article II of these By-Laws.

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ARTICLE IV

Officers

Section 4.1 Officers. The Corporation shall have such officers as are appointed from time to time by the Board of Directors.

Section 4.2 Election, Term of Office and Qualifications. Each officer (except such officers as may be appointed in accordance with the provisions of Section 4.3) shall be elected by the Board of Directors. Each such officer shall hold such office until such officer’s successor shall have been elected and qualified, or until such officer’s death, or until such officer shall have resigned in the manner provided in Section 4.4 or shall have been removed in the manner provided in Section 4.5.

Section 4.3 Subordinate Officers and Agents.    The Board of Directors may delegate to any officer or agent the power to appoint any subordinate officers or agents and to prescribe their respective terms of office, authorities and duties.

Section 4.4 Resignations. Any officer may resign at any time by giving written notice of such resignation to the Board of Directors. Unless otherwise specified in such written notice, such resignation shall take effect upon receipt thereof by the Board of Directors, and the acceptance of such resignation shall not be necessary to make it effective.

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Section 4.5 Removal. Any officer may be removed with or without cause at any meeting of the Board of Directors by affirmative vote of a majority of the directors then in office. Any officer or agent appointed in accordance with the provisions of Section 4.3 may be removed with or without cause at any meeting of the Board of Directors by affirmative vote of a majority of the directors present at such meeting, or at any time by any superior officer or agent upon whom such power of removal shall have been conferred by the Board of Directors.

Section 4.6 Vacancies. A vacancy in any office by reason of death, resignation, removal, disqualification or any other cause shall be filled for the unexpired portion of the term in the manner prescribed by these By-Laws for regular election or appointment to such office.

Section 4.7 General Duties of Officers. Each officer shall perform those duties and have such powers as from time to time may be assigned to him or her by the Board of Directors.

Section 4.8 Salaries. The salaries of the officers of the Corporation shall be fixed from time to time by the Board of Directors, except that the Board of Directors may delegate to any person the power to fix the salaries or other compensation of any officers or agents appointed in accordance with the provisions of Section 4.3. No officer shall be prevented from receiving such salary by reason of the fact that such officer is also a director of the Corporation.

ARTICLE V

Execution of Instruments and

Deposit of Corporate Funds

Section 5.1 Execution of Instruments Generally. The Board of Directors may authorize any officer or officers, or agent or agents, to enter into any contract or execute and deliver any instrument in the name and on behalf of the Corporation, and such authorization may be general or confined to specific instances.

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Section 5.2 Borrowing. No loans or advance shall be obtained or contracted for, by or on behalf of the Corporation and no negotiable paper shall be issued in its name, unless and except as authorized by the Board of Directors. Such authorization may be general or confined to specific instances. Any officer or agent of the Corporation thereunto so authorized may obtain loans and advances for the Corporation, and for such loans and advances may make, execute and deliver promissory notes, bonds, or other evidences of indebtedness of the Corporation. Any officer or agent of the Corporation thereunto so authorized may pledge, hypothecate or transfer as security for the payment of any and all loans, advances, indebtedness and liabilities of the Corporation, any and all stocks, bonds, other securities and other personal property at any time held by the Corporation, and to that end may endorse, assign and deliver the same and do every act and thing necessary or proper in connection therewith.

Section 5.3 Deposits. All funds of the Corporation not otherwise employed shall be deposited from time to time to its credit in such banks or trust companies or with such bankers or other depositaries as the Board of Directors may select, or as may be selected by any officer or officers or agent or agents authorized so to do by the Board of Directors. Endorsements for deposit to the credit of the Corporation in any of its duly authorized depositaries shall be made in such manner as the Board of Directors from time to time may determine.

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Section 5.4 Checks, Drafts, etc. All checks, drafts or other orders for the payment of money, and all notes or other evidences of indebtedness issued in the name of the Corporation, shall be signed by such officer or officers or agent or agents of the Corporation, and in such manner, as from time to time shall be determined by the Board of Directors.

Section 5.5 Proxies. Proxies to vote with respect to shares of stock of other corporations owned by or standing in the name of the Corporation may be executed and delivered from time to time on behalf of the Corporation by the President or by any other person or persons thereunto authorized by the Board of Directors.

Section 5.6 Other Contracts and Instruments. All other contracts and instruments binding the Corporation shall be executed in the name and on the behalf of the Corporation by those officers, employees or agents of the Corporation as may be authorized by the Board of Directors. That authorization may be general or confirmed to specific instances.

ARTICLE VI

Stock

Section 6.1 Certificates. The shares of the Corporation shall be represented by certificates, provided that the Board of Directors may provide by resolution or resolutions that some or all of any or all classes or series of stock shall be uncertificated shares. Any such resolution shall not apply to shares represented by a certificate until such certificate is surrendered to the Corporation. Every holder of stock represented by certificates shall be entitled to have a certificate signed by or in the name of the Corporation by the chairperson or vice chairperson of the Board of Directors, if any, or the president or a vice president, and by the treasurer or an assistant treasurer, or

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the secretary or an assistant secretary, of the Corporation certifying the number of shares owned by such holder in the Corporation. Any of or all the signatures on the certificate may be a facsimile. In case any officer, transfer agent or registrar who has signed or whose facsimile signature has been placed upon a certificate shall have ceased to be such officer, transfer agent, or registrar before such certificate is issued, it may be issued by the Corporation with the same effect as if such person were such officer, transfer agent, or registrar at the date of issue.

Section 6.2 Lost, Stolen or Destroyed Stock Certificates; Issuance of New Certificates. The Corporation may issue a new certificate of stock in the place of any certificate theretofore issued by it, alleged to have been lost, stolen or destroyed, and the Corporation may require the owner of the lost, stolen or destroyed certificate, or such owner’s legal representative, to give the Corporation a bond sufficient to indemnify it against any claim that may be made against it on account of the alleged loss, theft or destruction of any such certificate or the issuance of such new certificate.

ARTICLE VII

Record Dates

Section 7.1 Record Dates.

(a) In order that the Corporation may determine the stockholders entitled to notice of or to vote at any meeting of stockholders or any adjournment thereof, the Board of Directors may fix a record date, which record date shall not precede the date upon which the resolution fixing the record date is adopted by the Board of Directors, and which record date shall not be more than sixty (60) nor less than ten (10) days before the date of such

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meeting. If no record date is fixed by the Board of Directors, the record date for determining stockholders entitled to notice of and to vote at a meeting of stockholders shall be at the close of business on the day next preceding the day on which notice is given, or if notice is waived by all of the stockholders, at the close of business on the day next preceding the day on which such meeting is held. A determination of stockholders of record entitled to notice of or to vote at a meeting of stockholders shall apply to any adjournment of the meeting; provided, however, that the Board of Directors may fix a new record date for such adjourned meeting.

(b) In order that the Corporation may determine the stockholders entitled to consent to corporate action in writing without a meeting, the Board of Directors may fix a record date, which record date shall not precede the date upon which the resolution fixing the record date is adopted by the Board of Directors and which date shall not be more than ten (10) days after the date upon which the resolution fixing the record date is adopted by the Board of Directors. If no record date has been fixed by the Board of Directors, the record date for determining stockholders entitled to consent to corporate action in writing without a meeting, when no prior action by the Board of Directors is required by the General Corporation Law of the State of Delaware shall be the first date on which a signed written consent setting forth the action taken or proposed to be taken is delivered to the Corporation by delivery to its registered office in the State of Delaware, its principal place of business or an officer or agent of the Corporation having custody of the books in which proceedings of meetings of stockholders are recorded. Delivery made to the Corporation at its registered office shall be made by personal delivery or by certified or registered mail, return receipt requested. If no record date has been fixed by the Board of Directors and

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prior action by the Board of Directors is required by the General Corporation Law of the State of Delaware, the record date for determining stockholders entitled to consent to corporate action in writing without a meeting shall be at the close of business on the day on which the Board of Directors adopts the resolution taking such prior action.

(c) In order that the Corporation may determine the stockholders entitled to receive payment of any dividend or other distribution or allotment of any rights or the stockholders entitled to exercise any rights in respect of any change, conversion or exchange of stock, or for the purpose of any other lawful action, the Board of Directors may fix a record date, which record date shall not precede the date upon which the resolution fixing the record date is adopted, and which record date shall be not more than sixty (60) days prior to such action. If no record date is fixed, the record date for determining the stockholders for any such purpose shall be at the close of business on the day on which the Board of Directors adopts the resolution relating thereto.

ARTICLE VIII

Corporate Seal

Section 8.1 Corporate Seal. The corporate seal shall be circular in form and shall bear the name of the Corporation and words and figures denoting its organization under the laws of the State of Delaware and the year thereof and otherwise shall be in such form as shall be approved from time to time by the Board of Directors.

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ARTICLE IX

Fiscal Year

Section 9.1 Fiscal Year. The fiscal year of the Corporation shall be the calendar year.

ARTICLE X

Amendments

Section 10.1 Amendments. All By-Laws of the Corporation may be amended or repealed, and new By-Laws may be made, by an affirmative vote of a majority of the votes cast at any annual or special stockholders’ meeting by holders of outstanding shares of stock of the Corporation entitled to vote, or by an affirmative vote of a majority of the directors present at any organizational, regular, or special meeting of the Board of Directors.

ARTICLE XI

Action Without A Meeting

Section 11.1 Action Without A Meeting. Any action which might have been taken under these By-Laws by a vote of the stockholders at a meeting thereof may be taken without a meeting, without prior notice and without a vote, if a consent in writing setting forth the action so taken, shall be individually signed and dated by the holders of outstanding shares of stock of the Corporation having not less than the minimum number of votes that would be necessary to authorize or take such action at a meeting at which all shares entitled to vote thereon were present and voted, provided that no written consent will

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be effective unless the necessary number of written consents is delivered to the Corporation within sixty (60) days of the earliest delivered consent to the Corporation, and provided further that prompt notice shall be given to those stockholders who have not so consented if less than unanimous written consent is obtained. Any action which might have been taken under these By-Laws by vote of the directors at any meeting of the Board of Directors or any committee thereof may be taken without a meeting if all the members of the Board of Directors or such committee, as the case may be, consent thereto in writing, and the writing or writings are filed with the minutes of the Board of Directors or such committee.

ARTICLE XII

Indemnification and Advancement of Expenses

Section 12.1 Indemnification. The Corporation shall indemnify and hold harmless, to the fullest extent permitted by, and in the manner permissible under, applicable law as it presently exists or may hereafter be amended, any person who was or is a party or is threatened to be made a party to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative (a “proceeding”), by reason of the fact that the person is or was a director, officer, employee or agent of the Corporation, or is or was serving at the request of the Corporation as a director, trustee, partner, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise or nonprofit entity against all expenses (including attorneys’ fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by such person in connection with such proceeding.

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Section 12.2 Expense Advance. Expenses (including attorneys’ fees) incurred by an officer or director of the Corporation in defending any civil, criminal, administrative or investigative action, suit or proceeding may be paid by the Corporation in advance of the final disposition of such action, suit or proceeding upon receipt of an undertaking by or on behalf of such officer or director to repay such amount if it shall ultimately be determined that such person is not entitled to be indemnified by the Corporation as authorized in this Article. Such expenses (including attorneys’ fees) incurred by former directors and officers or other employees and agents of the Corporation may be so paid upon such terms and conditions, if any, as the Board of Directors deems appropriate.

Section 12.3 Nonexclusivity. The indemnification and advancement of expenses provided by, or granted pursuant to, the other Sections of this Article shall not be deemed exclusive of any other rights to which those seeking indemnification or advancement of expenses may be entitled under any statute, bylaw, agreement, vote of stockholders or disinterested directors or otherwise, both as to action in his or her official capacity and as to action in another capacity while holding such office.

Section 12.4 Insurance. The Corporation shall have power to purchase and maintain insurance on behalf of any person who is or was a director, officer, employee or agent of the Corporation, or is or was serving at the request of the Corporation as a director, trustee, partner, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise or nonprofit entity against any liability asserted against him or her and incurred by him or her in any such capacity, or arising out of his or her status as such, whether or not the Corporation would have the power to indemnify him or her against such liability under the provisions of this Article or Section 145 of Title 8 of the Delaware Code relating to the General Corporation Law of the State of Delaware.

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Section 12.5 Other Indemnification. The Corporation’s obligation, if any, to indemnify any person who was or is serving at its request as a director, trustee, partner, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise or nonprofit entity shall be reduced by any amount such person may collect as indemnification from such other corporation, partnership, joint venture, trust or other enterprise or nonprofit entity or from insurance.

Section 12.6 Continuation of Indemnification. The indemnification and advancement of expenses provided by, or granted pursuant to, this Article shall, unless otherwise provided when authorized or ratified, continue as to a person who has ceased to be a director, trustee, partner, officer, employee or agent and shall inure to the benefit of the heirs, executors and administrators of such a person.

Section 12.7 Amendment or Repeal. Any repeal or modification of the foregoing provisions of this Article shall not adversely affect any right or protection hereunder of any person in respect of any act or omission occurring prior to the time of such repeal or modification.

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Exhibit 99.1

Lantheus Completes Merger with Progenics

NORTH BILLERICA, Mass. and NEW YORK—(BUSINESS WIRE)—June 22, 2020—Lantheus Holdings, Inc. (the “Company”) (NASDAQ: LNTH), the parent company of Lantheus Medical Imaging, Inc. (“LMI”), a global leader in the development, manufacture and commercialization of innovative diagnostic imaging agents and products, today announced that it has completed its previously announced merger with Progenics Pharmaceuticals, Inc. (“Progenics”) (Nasdaq: PGNX), an oncology company developing innovative medicines and artificial intelligence to find, fight and follow cancer. The merger agreement was first announced on October 2, 2019.

“Today marks an important day for Lantheus and Progenics. This combination forms an innovative company with a diversified diagnostics and therapeutics portfolio,” said Mary Anne Heino, Lantheus President and Chief Executive Officer. “The transaction leverages Lantheus’ long-standing expertise in complex manufacturing, supply chain and commercial excellence, with Progenics’ three leading FDA approved products, clinical pipeline and development capabilities. We’re excited to welcome the talented Progenics employees to the Lantheus organization to help build upon our solid foundation.”

Upon completion of the merger, Progenics stockholders received, for each share of Progenics common stock, 0.31 of a share of Lantheus common stock and one non-tradeable contingent value right, which is payable in two contingent payments, subject to a cap, upon the achievement of certain milestones related to the financial performance of PyL^TM (¹⁸F-DCFPyL), Progenics’ prostate-specific membrane antigen targeted imaging agent designed to visualize prostate cancer.

The Company will continue to trade on Nasdaq under the ticker symbol LNTH. Progenics is being delisted.

About Lantheus Holdings, Inc. and Lantheus Medical Imaging, Inc.

Lantheus Holdings, Inc. is the parent company of LMI, a global leader in the development, manufacture and commercialization of innovative diagnostic imaging agents and products. LMI provides a broad portfolio of products, including the echocardiography contrast agent DEFINITY^® Vial for (Perflutren Lipid Microsphere) Injectable Suspension and TechneLite^® (Technetium Tc99m Generator), a technetium-based generator that provides the essential medical isotope used in nuclear medicine procedures. The Company is headquartered in North Billerica, Massachusetts with offices in Puerto Rico and Canada. For more information, visit www.lantheus.com.

About Progenics

Progenics is an oncology company focused on the development and commercialization of innovative targeted medicines and artificial intelligence to find, fight and follow cancer, including: therapeutic agents designed to treat cancer (AZEDRA^®, 1095, and PSMA TTC); prostate-specific membrane antigen (“PSMA”) targeted imaging agents for prostate cancer (PyL^™ and 1404); and imaging analysis technology (aBSI and

PSMA AI). Progenics has three commercial products, AZEDRA, for the treatment of patients with unresectable, locally advanced or metastatic pheochromocytoma or paraganglioma (rare neuroendocrine tumors of neural crest origin) who require systemic anticancer therapy; and oral and subcutaneous formulations of RELISTOR^® (methylnaltrexone bromide) for the treatment of opioid-induced constipation, which are partnered with Bausch Health Companies Inc. Progenics is headquartered in New York, New York with manufacturing facilities in Somerset, New Jersey. Additional information about Progenics is available at www.progenics.com.

Safe Harbor for Forward-Looking and Cautionary Statements

This document contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 that are subject to risks and uncertainties and are made pursuant to the safe harbor provisions of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. Such statements are based upon current plans, estimates and expectations that are subject to various risks and uncertainties. The inclusion of forward-looking statements should not be regarded as a representation that such plans, estimates and expectations will be achieved. Words such as “anticipate,” “expect,” “project,” “intend,” “believe,” “may,” “will,” “should,” “plan,” “could,” “target,” “contemplate,” “estimate,” “predict,” “potential,” “opportunity,” “creates” and words and terms of similar substance used in connection with any discussion of future plans, actions or events identify forward-looking statements. All statements, other than historical facts, including the expected benefits of the merger, such as efficiencies, cost savings, synergies, revenue growth, creating shareholder value, growth potential, market profile, enhanced competitive position, and financial strength and flexibility; the competitive ability and position of the combined company; and any assumptions underlying any of the foregoing, are forward-looking statements. Important factors that could cause actual results to differ materially from Lantheus’ plans, estimates or expectations could include, but are not limited to: (i) the merger may involve unexpected costs or liabilities; (ii) the effect of the merger on the ability of Lantheus to maintain relationships with customers, suppliers and others with whom Lantheus does business, or on Lantheus’ operating results and business generally; (iii) Lantheus’ business may suffer as a result of disruption of management’s attention due to the merger; (iv) the outcome of any legal proceedings related to the merger; (v) Lantheus may be adversely affected by other economic, business, and/or competitive factors, including the ongoing COVID-19 pandemic; (vi) risks that the merger disrupts current plans and operations and the potential difficulties in employee retention as a result of the merger; (vii) risks that the anticipated benefits of the merger or other commercial opportunities may otherwise not be fully realized or may take longer to realize than expected; (viii) the impact of legislative, regulatory, competitive and technological changes; and (ix) expectations for future clinical trials, the timing and potential outcomes of clinical studies and interactions with regulatory authorities. Additional factors that may affect the future results of Lantheus are set forth in Lantheus’ filings with the SEC, including Lantheus’ most recently filed Annual Report on Form 10-K, subsequent Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and other filings with the SEC, which are available on the SEC’s website at www.sec.gov. Readers are urged to consider these factors carefully in evaluating these forward-looking statements, and not to place undue reliance on any forward-looking statements. Readers should also carefully review the risk factors described in other documents that Lantheus files from time to time with the SEC. The forward-looking statements in this document speak only as of the date of these materials. Except as required by law, Lantheus assumes no obligation to update or revise these forward-looking statements for any reason, even if new information becomes available in the future.

Investors:

Mark Kinarney

Senior Director, Investor Relations

978-671-8842