AMENDED AND RESTATED VOTING AGREEMENT

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Exhibit 10.3

AMENDED AND RESTATED VOTING AGREEMENT

THIS AMENDED AND RESTATED VOTING AGREEMENT is dated as of March 29, 2005

by and among Molecular Insight Pharmaceuticals, Inc., a Massachusetts

corporation (the "Company"), the holders of the Company's Series A Convertible

Preferred Stock set forth on the signature page hereto (the "Series A Holders"),

the holders of the Company's Series B Convertible Preferred Stock set forth on

the signature page hereto (the "Series B Holders"), the holders of the Company's

Series C Convertible Preferred Stock set forth on the signature page hereto (the

"Series C Holders"), and certain holders of the Company's Common Stock as set

forth on the signature page hereto (the "Common Stockholders" and together with

the Series C Holders, Series B Holders and the Series A Holders, the

"Stockholders").

WHEREAS, the Company and certain holders of its Common Stock, Series A

Convertible Preferred Stock and Series B Convertible Preferred Stock previously

entered into a Voting Agreement dated March 4, 2004 (the "Prior Agreement")

which provided, inter alia, for certain voting agreements relating to the

election of members to the Company's Board of Directors (the "Board of

Directors"); and

WHEREAS, the Company desires to sell to the Series C Holders, and the

Series C Holders desire to purchase, shares of Series C Convertible Preferred

Stock ("Series C Preferred Stock") and, as a condition to such purchase and

sale, the Series C Holders require certain changes to the Prior Agreement.

NOW, THEREFORE, in consideration of the mutual covenants and agreements

contained herein and the investment by the Series C Holders under that certain

Stock Purchase Agreement (as defined below), the receipt and sufficiency of

which are hereby acknowledged, the parties hereto agree as follows:

Section 1. Election of Directors. At any time at which stockholders of the

Company have the right to, or vote for or consent in writing to, the election of

directors of the Company, the Stockholders hereby agree to vote, or consent in

writing as to, all shares of capital stock of the Company then owned by them in

favor of the following actions to:

(a) cause the election to the Board of Directors of one (1)

representative designated by David Barlow ("Series A Director"), who shall

initially be David Barlow; provided, however that if David Barlow is removed as

the Series A Director for cause (as defined in Section 1(h) below) then the

Series A Director shall be designated by the Series A Holders holding a majority

of the shares of the Series A Convertible Preferred Stock; and

(b) cause the election to the Board of Directors of one (1)

representative designated by Cerberus Partners, L.P. (the "Series B Director"),

who shall initially be Daniel Frank and who shall thereafter be selected by

Cerberus Partners, L.P.; and

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(c) subject to clause (i) below, cause the election to the Board of

Directors of one (1) representative designated by Cerberus Partners, L.P. (the

"Series C Director" and, together with the Series A Director and the Series B

Director, the "Investor Directors"), who shall initially be Andrew Jay; and

(d) cause the election to the Board of Directors of one (1) member

who shall be the President of the Company (the "Management Director"), who shall

initially be John Babich; provided that if the Company shall not have a

President, such position held by the Chief Executive Officer of the Company or,

if there is no President or Chief Executive Officer then serving for the

Company, such individual serving in a similar capacity; and

(e) cause the election to the Board of Directors of three (3)

members with appropriate industry experience who shall be designated by the

President of the Company in consultation with the senior management of the

Company and approved by the Series B Director, which approval shall not be

unreasonably withheld or delayed (the "Industry Directors"), who shall initially

be Harry Stylli, Kim Lamon and William Eckelman.

(f) The Company shall cause the nomination for election to the Board

of Directors of the individuals set forth in clauses (a) through and including

(e) above. Each of the directors designated in this Section 1 shall be elected

at any annual or special meeting of stockholders (or by written consent in lieu

of a meeting of stockholders) and shall serve until his or her successor is

elected and qualified, or until his or her earlier resignation or removal.

(g) The Board of Directors shall remain seven (7) members unless

changed by the vote or written consent of (i) the holders of at least fifty

percent (50%) of the then-outstanding shares of capital stock, with all classes

voting together as a single class, (ii) the holders of at least fifty percent

(50%) of the Series A Convertible Preferred Stock, (iii) the holders of at least

fifty percent (50%) of the Series B Convertible Preferred Stock and (iv) the

holders of at least fifty percent (50%) of the Series C Preferred Stock (the

vote or consent required by clauses (i) through (iv) being the "Requisite

Vote").

(h) For purposes of Section 1(a), "cause" shall mean either (i) the

conviction of, or pleading of nolo contendre to, a felony or (ii) the commission

of an act of fraud or embezzlement, in each case, by David Barlow.

(i) So long as Siemens Venture Capital GmbH ("Siemens") continues to

own Series C Preferred Stock having an aggregate Series C Stated Value of at

least Three Million Dollars ($3,000,000), Siemens shall be entitled to appoint

the Series C Director (when so appointed by Siemens, the Series C Director shall

be referred to as the "Siemens Director"); provided, however, that, upon a

Removal Event, Siemens shall immediately cease to have the right to appoint the

Series C Director and the Siemens Director shall be automatically and

immediately, without the need for any further corporate or Board of Directors

action or deed, removed from the Board of Directors. In the event of the

occurrence of a Removal Event

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described in clause (i) of the definition of Removal Event only, Siemens shall

once again have the right of appointment of the Series C Director if the Board

of Directors, acting at a duly called meeting and/or by written consent, adopts

a resolution abandoning, canceling or ending the Removal Event. This right to

appoint the Series C Director is personal to Siemens and, notwithstanding

anything to the contrary herein or in any of the Transaction Documents (as

defined in the Stock Purchase Agreement), such right shall not be assignable by

Siemens, including without limitation, to any transferee of Series C Preferred

Stock (or the Common Stock issuable upon conversion thereof) by Siemens. If the

Siemens Director shall be removed from the Board of Directors pursuant to a

Removal Event as set forth in this clause (i), the Company shall provide the

Siemens Director with prompt written notice thereof (without any obligation to

disclose the details of the applicable Removal Event), but the failure to give

any such notice shall not be a condition to, or otherwise serve as a basis to

prevent, any such removal. For purposes of Sections 1 and 3 herein, the

following definitions shall apply:

(1) "Co-Lead Investors" shall mean Cerberus Partners, L.P. and

MedCap Partners, L.P.

(2) "Qualified Public Offering" shall mean the closing of a firm

commitment underwritten public offering of shares of the Company's Common Stock

pursuant to a registration statement filed with the Securities and Exchange

Commission under the Securities Act of 1933, as amended, on form S-1 or its

equivalent, in which the Company's Common Stock is offered and sold to the

public at an initial public offering price equal to at least $5.00 per share,

with aggregate gross proceeds to the Company of not less than $30 million.

(3) "Removal Event" shall mean the soonest to occur of: (i) the

adoption of a resolution by the Board of Directors, acting at a duly called

meeting and/or by written consent, taking any action to pursue consideration of

any merger, consolidation, sale, lease or exchange of substantially all of its

assets, sale or exchange of its capital stock, or any other similar business

transaction involving the Corporation; (ii) June 30, 2007; and (iii) a Qualified

Public Offering.

(4) "Series C Stated Value" shall mean, with respect to each shares

of Series C Preferred Stock, $202.00, which amount shall be subject to

appropriate adjustment in the event of a stock dividend, stock split, reverse

stock split, reclassification, stock combination or other recapitalization

affecting the Series C Preferred Stock, all in accordance with the Company's

Articles of Organization, as amended to date.

(5) "Stock Purchase Agreement" shall mean that certain Stock

Purchase Agreement by and between the Company and the Series C Holders dated

March 29, 2005.

Section 2. Vacancies and Removal.

(a) Series A Director. The Series A Director may be removed during

his or her term of office, with or without cause, by and only by the affirmative

vote or written consent

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of the holders of a majority of the then-outstanding shares of Series A

Convertible Preferred Stock. Each of the Stockholders agrees to, and shall, vote

all of its shares of capital stock in the same manner as the vote cast or

consent given by the holders of the majority of the Series A Convertible

Preferred Stock on the matter described in the foregoing sentence. Any vacancy

in the office of a Series A Director shall be filled by a person designated

pursuant to the terms of Section 1(a) above and each of the Stockholders agrees

to vote, and shall vote, all of its shares of capital stock of the Company in

favor of such person.

(b) Series B Director. The Series B Director may be removed during

his or her term of office, with or without cause, by and only by the affirmative

vote or written consent of Cerberus Partners, L.P. Each of the Stockholders

agrees to, and shall, vote all of its shares of capital stock in the same manner

as the vote cast or consent given by Cerberus Partners, L.P. on the matter

described in the foregoing sentence. Any vacancy in the office of the Series B

Director shall be filled by a person designated pursuant to Section 1(b) above

and each of the Stockholders agrees to, and shall, vote all of its shares of

capital stock of the Company in favor of such person.

(c) Series C Director. The Series C Director may be removed during

his or her term of office, with or without cause, by and only by the affirmative

vote or written consent of Cerberus Partners, L.P.; provided, however, that if

Siemens has the right to appoint the Series C Director pursuant to Section 1(i)

then such Siemens Director may only be removed during his or her term of office,

with or without case, by and only by the affirmative vote or written consent of

Siemens. Each of the Stockholders agrees to, and shall, vote all of its shares

of capital stock in the same manner as the vote of or consent by Cerberus

Partners, L.P. or Siemens, as the case may be, on the matter described in the

foregoing sentence. Any vacancy in the office of the Series C Director shall be

filled by a person designated pursuant to Section 1