Exhibit 10.1

AMENDMENT TO SECURITIES PURCHASE AGREEMENT

This Amendment to Securities Purchase Agreement (hereinafter referred to as this
“Amendment”) dated as of November 30, 2006, is entered into by and among
NEOPROBE CORPORATION (the “Company”), a Delaware corporation, BIOMEDICAL VALUE
FUND, L.P. (“BVF”), a Delaware limited partnership, BIOMEDICAL OFFSHORE VALUE
FUND, LTD. (“BOVF” and together with “BVF,” the “BV Funds”), an exempted company
incorporated under the provisions of the Companies Law of the Cayman Islands,
and DAVID C. BUPP (“Bupp” and together with the BV Funds, each a “Purchaser” and
collectively, the “Purchasers”).

W I T N E S S E T H :

WHEREAS, the Company and the Purchasers are parties to that certain Securities
Purchase Agreement dated as of December 13, 2004 (hereinafter referred to as the
“Purchase Agreement”); and

WHEREAS, the Purchasers and the Company desire to amend the Purchase Agreement
in accordance with the terms and conditions of this Amendment.

NOW, THEREFORE, in consideration of the premises, the mutual covenants
hereinafter contained, and other good and valuable consideration, the receipt
and sufficiency of which are hereby acknowledged, the parties agree as follows:

Section 1. Definitions. Terms defined in the Purchase Agreement which are used
herein shall have the same meaning as set forth in the Purchase Agreement unless
otherwise specified herein.

Section 2. Effect of this Amendment. This Amendment shall not change, modify,
amend or revise the terms, conditions and provisions of the Purchase Agreement
or the Security Agreement, the terms and provisions of which are incorporated
herein by reference, except as expressly provided herein or in the replacement
Notes and Warrants executed in connection herewith and agreed upon by the
parties hereto. This Amendment is not intended to be nor shall it constitute a
novation or accord and satisfaction of the outstanding Obligations. The Company
and the Purchasers agree that, except as expressly provided herein or in other
documents executed in connection herewith, all terms and conditions of the
Purchase Agreement and Security Agreement shall remain and continue in full
force and effect. The Company acknowledges and agrees that the indebtedness
under the Purchase Agreement and Notes remains outstanding and is not
extinguished, paid, or retired by this Amendment, or any other agreements
between the parties hereto prior to the date hereof, and that the Company is and
continues to be fully liable for all Obligations contemplated by or arising out
of the Purchase Agreement, Security Agreement, Notes and Warrants, as amended or
replaced pursuant to this Amendment.

Section 3. Amendment of Purchase Agreement.

3.1 The following definitions appearing in Section 1 of the Purchase Agreement
are amended and replaced (except as to the definition of “Asset Disposition”,
for which only the first sentence thereof is amended and replaced) to read as
follows:

“Asset Disposition” shall mean the disposition, whether by sale, lease,
transfer, loss, damage, destruction, condemnation or otherwise, of any or all of
the assets of the Company or any of its Subsidiaries other than sales of
inventory in the ordinary course of business.
 

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“BOVF Note” shall mean the replacement senior secured convertible promissory
note issued to BOVF pursuant to the Amendment in the principal amount of
$3,600,000, substantially in the form attached to the Amendment as Exhibit A.

“BOVF Warrant” shall mean the replacement warrant issued to BOVF pursuant to the
Amendment, substantially in the form attached to the Amendment as Exhibit B.

“Bupp Note” shall mean the replacement senior secured convertible promissory
note issued to Bupp pursuant to the Amendment in the principal amount of
$100,000, substantially in the form attached to the Amendment as Exhibit A.

“BUPP Warrant” shall mean the replacement warrant issued to Bupp pursuant to the
Amendment, substantially in the form attached to the Amendment as Exhibit B.

“BVF Note” shall mean the replacement senior secured convertible promissory note
in the principal amount of $4,400,000 substantially in the form attached to the
Amendment as Exhibit A.

“BVF Warrant” shall mean the replacement warrant issued to BVF pursuant to the
Amendment, substantially in the form attached to the Amendment as Exhibit B.

3.2 The following Section 8.8 is hereby added to the Purchase Agreement:

8.8 Sale of Additional Equity Securities. The Company agrees (i) to use its
reasonable best efforts to commence on or before April 31, 2007, and continue
during the balance of the term of the Notes, the offering and sale of its equity
securities with aggregate gross proceeds during such period of up to $10,000,000
(an “Equity Sale”), and (ii) to apply not less than 50% of the Equity Proceeds
to repayment of the principal balance of the Notes. For this purpose, “Equity
Proceeds” means the actual cash proceeds received by the Company from any Equity
Sale, net of all costs incurred by the Company in connection with the offering
and sale of the securities, including without limitation all commissions and
placement agent fees and expense reimbursements, registration, listing and
qualifications fees, printers and accounting fees, and fees and disbursements of
Company counsel.

3.3 Section 9.6 of the Purchase Agreement is amended and replaced to read as
follows:

9.6 Dispositions of Assets. Except as provided in Section 9.6(a), (b), (c), or
(d) the Company will not, and will not permit any of its Subsidiaries, directly
or indirectly, to (i) convey, sell (pursuant to a sale/leaseback or otherwise),
lease, sublease, transfer or otherwise dispose of, or grant any Person an option
to acquire, in one transaction or a series of transactions, any material amount
of its property, business or assets, or the capital stock of or other equity
interests in any of its Subsidiaries, whether now owned or hereafter acquired,
or (ii) enter into any license, assignment, sharing or other transfer of
Intellectual Property of the Company or Subsidiaries, or rights therein, whether
through cooperative research and development agreements, strategic alliances,
agreements providing for the manufacturing, distribution or sale of products or
services of the Company or Subsidiaries, or otherwise (a “Partnering
Transaction”):
 
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(a) Bona fide sales of inventory, including, without limitation, real estate
acquired in the ordinary course of business, to customers for fair value in the
ordinary course of business and dispositions of obsolete equipment not used or
useful in the business;

(b) Asset Dispositions if all of the following conditions are met:

(i) the market value of assets sold or otherwise disposed of (by the Company and
its Subsidiaries taken as a whole) in any fiscal year do not exceed $500,000;

(ii) the Net Proceeds received is at least equal to the fair market value of
such assets;

(iii) at least 75% of the consideration received is cash;

(iv) not less than 50% of the Net Proceeds are applied to repayment of the
principal balance of the Notes;

(v) the assets disposed of in the Asset Disposition are not subject to a
security interest pursuant to the Security Agreement; and

(vi) no Event of Default then exists or shall result from such sale or other
disposition.

(c) Partnering Transactions if all of the following conditions are met:

(i) at least 50% of the consideration received is cash;

(ii) not less than 50% of the Partnering Proceeds are applied to repayment of
the principal balance of the Notes. For this purpose, “Partnering Proceeds”
means the proceeds thereof to the Company (inclusive of cash and the fair market
value of any property received as consideration for such Partnering
Transaction), net of all costs incurred by the Company in connection with or
pursuant to the Partnering Transaction, including without limitation all
transaction fees and expenses of the Company, license fees or royalty payments
required to be paid to third parties from proceeds, recording and transfer fees,
accounting fees, and fees and disbursements of Company counsel; and

(iii) the assets subject to the Partnering Transaction are not subject to a
security interest pursuant to the Security Agreement; and

(iv) no Event of Default then exists or shall result from such Partnering
Transaction.

(d) Partnering Transactions with contract manufacturers to effect the
outsourcing of formulation or manufacturing of products of the Company or
Subsidiaries, where any associated license of Intellectual Property to the
contract manufacturer is limited to those rights necessary to the formulation or
manufacture of products for the sole benefit of the Company.

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3.4 Section 9.8 of the Purchase Agreement is hereby deleted.

Section 4. Representations and Warranties of the Company. The Company hereby
represents and warrants, in addition to any other representations and warranties
contained in the Purchase Agreement, as follows:

(a) This Amendment constitutes a legal, valid and binding obligation of the
Company enforceable in accordance with its terms, except as enforceability may
be limited by applicable bankruptcy, insolvency, or similar laws affecting the
enforcement of creditors’ rights generally or by equitable principles relating
to enforceability;

(b) The Company has taken all necessary and appropriate corporate action for the
approval of this Amendment and the authorization of the execution, delivery and
performance hereof, and the execution and delivery of the BOVF Note, the BOVF
Warrant, the Bupp Note, the Bupp Warrant, the BVF Note and the BVF Warrant; and

(c) As of the date hereof and after giving effect to the amendments to the
Purchase Agreement contained herein, there is no Event of Default under the
Purchase Agreement or the Notes.

Section 5. Representations and Warranties of the Purchasers. Each Purchaser,
severally but not jointly, hereby represents and warrants, in addition to any
other representations and warranties contained in the Purchase Agreement, as
follows:

(a) This Amendment constitutes a legal, valid and binding obligation of the
Purchaser enforceable in accordance with its terms, except as enforceability may
be limited by applicable bankruptcy, insolvency, or similar laws affecting the
enforcement of creditors’ rights generally or by equitable principles relating
to enforceability;

(b) The Purchaser has taken all necessary and appropriate corporate action for
the approval of this Amendment and the authorization of the execution, delivery
and performance hereof, and the exchange of the replacement Notes and Warrants
for the Notes and Warrants currently outstanding.

Section 6. Closing. The closing of the transactions contemplated by this
Amendment, including the exchange of the replacement Notes and Warrants for the
currently outstanding Notes and Warrants, shall occur promptly following the
execution and delivery of this Amendment by the parties, which may be effected
as provided in Section 11.5 of the Agreement. Notwithstanding Section 11.5 of
the Agreement, the Company shall deliver by overnight delivery to each of the
Purchasers the replacement Notes and Warrants to the Purchasers, against
surrender by the Purchasers to the Company by overnight delivery of the
outstanding Notes and Warrants, and the closing shall be deemed complete upon
completion of all such deliveries.
 
Section 7. Governing Law. This Amendment has been executed and delivered and is
intended to be performed in the State of New York and shall be governed,
construed and enforced in all respects in accordance with the substantive laws
of the State of New York, except to the extent that the General Corporation Law
of Delaware shall apply.

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Section 8. Headings. The section headings used in this Amendment are for
convenience only and shall not be read or construed as limiting the substance or
generality of this Amendment.

Section 9. Amendment Expenses. The Company shall pay or reimburse, promptly on
demand, all costs and expenses incurred by the Purchasers in connection with
this Amendment, including without limitation attorneys’ fees and disbursements.

 
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IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be executed
by their respective duly authorized representatives as of the date and year
first written above.
 

        NEOPROBE CORPORATION  
   
   
    By:   /s/ Brent L. Larson  

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Name: Brent L. Larson  
Title: VP Finance/ CFO

 

        BIOMEDICAL VALUE FUND, L.P.  
   
By:
 
GREAT POINT GP, LLC,
its general partner
        By:   /s/ David Kroin  

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Name: David Kroin  
Title: Managing Director

 

        BIOMEDICAL OFFSHORE VALUE FUND, LTD.  
   
By:  
GREAT POINT PARTNERS, LLC,
its investment manager         By:   /s/ David Kroin  

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Name: David Kroin   Title: Managing Director

 

        DAVID C. BUPP  
   
   
    By:   /s/ David C. Bupp   

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