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                                                                   Exhibit 10.20

                        MOLECULAR INSIGHT PHARMACEUTICALS

                              CONSULTING AGREEMENT

     1. INTRODUCTION. This Agreement is made by and between William C. Eckelman,
Ph.D., ("Consultant"), with offices at 10432 Snow Point Drive, Bethesda, MD
20814, and Molecular Insight Pharmaceuticals, Inc., with principal offices at
160 Second Street, Cambridge, Massachusetts, 02142 ("Client").

     2. RETENTION AND DESCRIPTION OF SERVICES. During the term of this
Agreement, Consultant will furnish consulting services and advice as
specifically requested by client as provided in the attached Exhibit A.

     3. EFFECTIVE DATE AND TERM OF AGREEMENT. This Agreement shall be effective
beginning January 1 2005 and shall terminate on December 31, 2009, unless
terminated sooner in accordance with the provisions of Section 8 of this
Agreement. This Agreement may be extended for additional periods of time as
agreed by the mutual written consent of Consultant and Client.

     4. COMPENSATION AND EXPENSES. Client shall pay $12,500 monthly retainer in
consideration for the services performed by Consultant pursuant to and during
the term of this Agreement. Client shall also reimburse Consultant for travel
undertaken at Client's request. Consultant shall invoice Client monthly, in
arrears, and Client shall pay all invoices within 30 days of receipt.

     5. CONSULTANT AN INDEPENDENT CONTRACTOR. Consultant will furnish
Consultant's services as an independent contractor and not as an employee of
Client or for any company affiliated with Client. Consultant has no power or
authority to bind Client in any manner. Consultant is not entitled to any
medical coverage, life insurance, participation in Client's saving plan, or
other benefits afforded Client's regular employees, or those of Client's
affiliated companies unless otherwise specifically agreed by the parties hereto.

     6. CONFIDENTIAL INFORMATION, TRADE SECRETS AND INVENTIONS. Consultant will
treat as proprietary any information belonging to Client, Client's affiliated
companies, or any third parties, disclosed to Consultant in the course of
Consultant's services. Consultant assigns and agrees to assign Client or
Client's nominee all rights in inventions or other proprietary information
conceived by Consultant during the term of this Agreement with respect to any
work that Consultant performs under this Agreement. The provisions of this
section shall survive the termination of this Agreement.
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     7. INSIDE INFORMATION - SECURITIES LAWS VIOLATIONS. In the course of the
performance of Consultant's duties, it is expected Consultant will receive
information that is considered material inside information within the meaning
and intent of federal securities laws, rules, and regulations. Consultant will
not disclose this information directly or indirectly for Consultant, or as a
basis for advice to any other party concerning any decision to buy, sell, or
otherwise deal in Client's securities or those of any of Client's affiliated
companies.

     8. TERMINATION OF AGREEMENT BY NOTICE. Either party may terminate this
Agreement upon thirty (30) days' notice by registered or certified mail, return
receipt requested, addressed to the other party at the addresses listed above.
Except as provided in section 9 of this Agreement, if this Agreement is
terminated by either party, Client shall only be liable for payment of
consulting fees through the end of the calendar month in which termination of
this Agreement takes effect. The thirty (30) days' notice shall be measured
from the date the notice is posted.

     9. SUCCESSORS AND ASSIGNS. This Agreement shall be binding upon, and inure
to the benefit of, both parties and their respective successors and assigns,
including any corporation with which, or into which Client may be merged or
which may succeed to its assets or business, provided, however, that the
obligations of Consultant are personal and shall not be assigned by Consultant.
In the event Client does in fact merge with another corporation or another
corporation succeeds to its assets, stock or business, neither Client nor its
successor(s) or assignee(s) shall terminate this Agreement for any reason.

     10. AMENDMENT. This Agreement may be amended or modified only by a written
instrument executed by both Client and Consultant.

     11. SEPARABILITY AND WAIVER. If any of the terms, provisions, or conditions
of this Agreement or the application thereof to any circumstances shall be ruled
invalid or unenforceable, the validity or enforceability of the remainder of
this Agreement shall not be affected thereby, and each of the other terms,
provisions, and conditions of this Agreement shall be valid and enforceable to
the fullest extent permitted by law.

     A waiver or consent regarding any term, provision, or condition of this
Agreement given by either party shall be effective only in that instance and
shall not be construed as a bar or waiver of any right on any other occasion.

     12. INDEMNIFICATION. Client shall indemnify and hold harmless Consultant,
its agents, successors and assigns against claims, suits, demands, damages,
judgments, expenses and cost, including reasonable attorney fees and court
costs, caused by the negligence, omission or willful acts of Client, its
employees, agents, subcontractors and representatives. In addition, Client shall
pay the reasonable attorney fees, costs and expenses incurred by Consultant
in connection with any legal proceeding involving Client in which Consultant
must respond to any subpoena,

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appear at deposition, or testify in any legal proceeding as a result of
Consultant's relationship with Client.

     13. ENTIRE AGREEMENT. This Agreement constitutes the entire agreement
between the parties and supersedes all prior agreements and understandings
between the parties.

     14. GOVERNING LAW. This Agreement is subject to and shall be interpreted in
accordance with the laws of Massachusetts.

     15. WAIVER OF RIGHT TO JURY TRIAL. Client and Consultant hereby waive trial
by jury in any action, proceeding or counterclaim brought by either of the
parties hereto against the other.

     16. NOTICES. Any notice or communication required to be given by either
party to this Agreement shall be in writing and shall be hand delivered or sent
by certified mail, return receipt requested, or by confirmed facsimile
transmission to the addresses indicated below or such other address as either
party may specify to the other in writing.


For Consultant,
William C. Eckelman, Ph.D.

/s/ William C. Eckelman
------------------------------

For Client,
Molecular Insight Pharmaceuticals, Inc.

/s/ John E. McCray
-----------------------
John E. McCray
COO

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                                    EXHIBIT A

You will serve as Chief Scientific Advisor to the client's President and
scientific staff on all scientific aspects of the client's portfolio and
strategic planning.

You will also be expected to provide assistance when needed to the client's
Research and Development team, as well as outside consultants, in order that the
client's mission and goals are achieved.

You will report to the President and Chief Scientific Officer, Dr. John Babich.

You will also serve as Chairman of the client's Scientific Advisory Board.


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