EMPLOYMENT
      AGREEMENT

     

    This
      EMPLOYMENT AGREEMENT (this
      “Agreement”)
      is
      made and entered into this August 3, 2007 by and between David P. Wright (the
      “Executive”)
      and
      Healthcare Acquisition Corp., a Delaware corporation (the “Company”).

     

    WITNESSETH:

     

    WHEREAS,
      the
      Executive has been employed by PharmAthene, Inc., a Delaware corporation
      (“PharmAthene”)
      and a
      party to the Agreement and Plan of Merger, dated as of January 19, 2007 (the
      “Merger
      Agreement”),
      with
      the Company and PAI Acquisition Corp. pursuant to which it is contemplated
      that,
      subject to satisfaction or waiver of all conditions set forth in the Merger
      Agreement, PharmAthene will become the sole wholly-owned subsidiary of the
      Company and the Company will change its name to PharmAthene, Inc.;
      and

     

    WHEREAS,
      in
      connection with the merger, the parties desire to transition the Executive
      from
      the position of Chief Executive Officer of PharmAthene, Inc., the pre-merger
      company and merger party, to Chief Executive Officer of the Company;
      and

     

    WHEREAS,
      in
      entering into this Agreement, the Board of Directors of the Company (the
“Board”)
      desires to provide the executive with substantial incentives to serve the
      Company as one of its senior executives performing at the highest level of
      leadership and stewardship to manage the Company’s future growth and development
      and to maximize the returns to the Company’s stockholders;

     

    NOW,
      THEREFORE,
      in
      consideration of the foregoing and of the mutual covenants and obligations
      hereinafter set forth, the parties hereto hereby agree as follows:

     

    
      	
              1.

            	
              Employment;
                Term. The
                Company hereby agrees, provided that the Executive continues to be
                employed by PharmAthene on the date of the consummation of the
                contemplated merger, to employ the Executive and the Executive hereby
                accepts employment by the Company upon the terms and conditions
                hereinafter set forth for the period commencing on the date of
                consummation of the contemplated merger (the “Effective
                Date”)
                and ending on the first anniversary of such date. The term of this
                Agreement shall be automatically extended for an additional year
                on each
                anniversary of the date hereof unless written notice of non-extension
                is
                provided by either party to the other party at least 90 days prior
                to such
                anniversary. The period of the Executive’s employment under this
                Agreement, as it may be terminated or extended from time to time
                as
                provided herein is referred to as the “Employment
                Period.”

            


    

     

    
      	
              2.

            	
              Position
                and Duties.  

            


    

     

    
      	 	
              a.

            	
              Position
                and Duties Generally. The
                Executive shall be employed by the Company in the position of Chief
                Executive Officer and shall faithfully render such executive, managerial,
                administrative and other services as are customarily associated with
                and
                incident to such position and as the Company may from time to time
                reasonably require consistent with such position. The Executive shall
                report to the Board of Directors or the Board’s
                designee.

            


    

     

     

    
      
        
        

      

      
        1

        
          

        

      

      
        
        

      

    

     

     

    
      	 	
              b.

            	
              Other
                Positions. The
                Executive shall hold such other positions and executive offices with
                the
                Company and/or of any of the Company’s subsidiaries or affiliates as may
                from time to time be authorized by the Board. The Executive shall
                not be
                entitled to any compensation other than the compensation provided
                for
                herein for serving during the Employment Period in any other office
                or
                position of the Company or any of its subsidiaries or affiliates,
                unless
                the Compensation Committee specifically approves such additional
                compensation.

            


    

     

    
      	 	
              c.

            	
              Devotion
                to Employment. Except
                for vacation time taken in accordance with the Company’s vacation policy
                in effect from time to time and in accordance with the terms of this
                Agreement and for absences due to temporary illness, the Executive
                shall
                be a full-time employee of the Company and shall devote full time,
                attention and efforts during the Employment Period to the business
                of the
                Company and the duties required of him in his position. During the
                Employment Period, the Executive shall not be engaged in any other
                business activity which, in the reasonable judgment of the Board
                or its
                designee, conflicts with the duties of the Executive hereunder, whether
                or
                not such activity is pursued for gain, profit or other pecuniary
                advantage.

            


    

     

    
      	 	
              d.

            	
              Director
                Status. The
                Company shall (i) nominate the Executive for re-election to the Board
                throughout the Employment Period on each occasion during the Employment
                Period when his term as a director is scheduled to expire, (ii) in
                all
                proxy and other materials, recommend that the stockholders vote in
                favor
                of the Executive’s election as a director, (iii) not directly or
                indirectly oppose or withdraw support from the Executive, and (iv)
                solicit
                proxies from the stockholders authorizing the named proxy holders
                to vote
                in favor of the Executive’s candidacy. The Executive agrees that in the
                event of the termination of his employment under this Agreement or
                of his
                resignation, he shall tender his resignation from the Board as
                well.

            


    

     

    
      	 	
              e.

            	
              Other
                Directorships. The
                Executive may serve as a non-management director of one or more businesses
                or not-for-profit organizations provided, however, that the Executive
                may
                not serve in such capacity with respect to more than two organizations
                at
                any one time without the prior written approval of the
                Board.

            


    

     

    
      	
              3.

            	
              Compensation;
                Reimbursement. 

            


    

     

    
      	 	
              a.

            	
              Base
                Salary. For
                the Executive’s services, the Company shall pay to the Executive an annual
                base salary of not less than $392,000 per annum, payable in equal
                periodic
                installments according to the Company’s customary payroll practices, but
                no less frequently than monthly. The Executive’s base salary shall be
                subject to review annually by the Compensation Committee and shall
                be
                subject to increase at the option and sole discretion of the Compensation
                Committee.

            


    

     

    
      	 	
              b.

            	
              Bonus.
                The Executive shall be eligible to receive at the sole discretion
                of the
                Compensation Committee, an annual cash bonus of up to an additional
                30% of
                his base salary. In addition, the Executive may be eligible for additional
                bonuses at the option and sole discretion of the Compensation Committee
                based upon based upon the achievement of certain pre-determined
                performance milestones.

            


    

     

     

    
      
        
        

      

      
        2

        
          

        

      

      
        
        

      

    

     

     

    
      	 	
              c.

            	
              Benefits
                Generally. 

            


    

     

    
      	 	
              i.

            	
              In
                addition to the salary and cash bonus described above, the Executive
                shall
                be entitled during the Employment Period to participate in such employee
                benefit plans and programs of the Company, and shall be entitled
                to such
                other fringe benefits, as are from time to time made available by
                the
                Company generally to employees of the level, position, tenure, salary,
                age, health and other qualifications of the Executive including,
                without
                limitation, medical, dental and vision insurance coverage for the
                Executive and his dependents, disability, death benefit and life
                insurance
                and pension plans. 

            


    

     

    
      	 	
              ii.

            	
              Without
                limiting the generality of the foregoing, the Executive shall be
                eligible
                for such awards, if any, including stock and stock options under
                the
                Company’s 2007 Long-Term Incentive Plan or such other plan as the Company
                may from time to time put into effect as shall be granted to the
                Executive
                by the Compensation Committee or other appropriate designee of the
                Board
                acting in its sole discretion. 

            


    

     

    
      	 	
              iii.

            	
              The
                Executive acknowledges and agrees that the Company does not guarantee
                the
                adoption or continuance of any particular employee benefit plan and
                participation by the Executive in any such plan or program shall
                be
                subject to the rules and regulations applicable thereto.
                

            


    

     

    
      	 	
              d.

            	
              Stock
                Options.  

            


    

     

    
      	 	
              i.

            	
              Contemporaneously
                with the execution of this Agreement, Executive has been granted
                a stock
                option to purchase 780,000 shares of the Company’s common stock (the
                “Initial
                Stock Option”)
                pursuant to the Company’s 2007 Long-Term Incentive Plan and subject to the
                terms and conditions of such Plan and of a stock option agreement,
                dated
                the date hereof, by the Company and the Executive which shall be
                executed
                contemporaneously with the execution of this Agreement.
                

            


    

     

    
      	 	
              ii.

            	
              The
                Initial Stock Option shall have a term of 10 years and, subject to
                possible acceleration of vesting as otherwise provided herein, the
                Initial
                Stock Option shall vest over a 5 year period with 25% of the shares
                under
                the Initial Stock Option being exercisable on the first anniversary
                of the
                grant date and the remainder of the Initial Stock Option vesting
                monthly
                on a pro-rata basis over the succeeding 48 months following the first
                anniversary such that 100% of the shares under the Initial Stock
                Option
                shall be exercisable after 5 years from the grant date.
                

            


    

     

    
      	 	
              iii.

            	
              The
                per share exercise price of the Initial Stock Option shall be the
                fair
                market value of a share of the common stock of the Company on the
                date of
                grant as determined by the Compensation Committee in accordance with
                Section 409A of the Internal Revenue Code of 1986, as amended (the
                “Code”)
                and the regulations of and the interpretive guidance issued by the
                Department of the Treasury. 

            


    

     

     

    
      
        
        

      

      
        3

        
          

        

      

      
        
        

      

    

     

     

    
      	 	
              iv.

            	
              The
                number of shares subject to the Option shall be equitably adjusted
                in the
                event of any change in the number of shares of the Company’s commons stock
                outstanding by reason of any stock dividend or split, reverse stock
                split,
                recapitalization, merger, consolidation, combination or exchange
                of shares
                or similar corporate change occurring after the commencement of the
                Executive’s employment under this
                Agreement.

            


    

     

    
      	 	
              v.

            	
              Additional
                future grants of stock options may be made to the Executive at the
                discretion of the Compensation Committee.


            


    

     

    
      	 	
              e.

            	
              Restricted
                Stock Awards. 

            


    

     

    
      	 	
              i.

            	
              Contemporaneously
                with the execution of this Agreement, the Executive has been granted
                a
                restricted stock award of 100,000 shares of the Company’s common stock
                (the “Initial
                Restricted Stock Award”)
                pursuant to the Company’s 2007 Long-Term Incentive Plan and subject to the
                terms and conditions of such Plan and of a restricted stock agreement,
                dated the date hereof, by the Company and the Executive which shall
                be
                executed contemporaneously with the execution of this Agreement.
                The
                shares issued under the Initial Restricted Stock Award (the “Restricted
                Shares”)
                shall, subject to possible acceleration of vesting as otherwise provided
                herein, vest over a 5 year period with 25% of the Restricted Shares
                subject to the Initial Restricted Stock Award vesting on the first
                anniversary of the grant of the Initial Restricted Stock Award and
                the
                remainder vesting monthly on a pro-rata basis over the succeeding
                48
                months following the first anniversary such that 100% of the Restricted
                Shares shall be vested after 5 years from the grant date. All Restricted
                Shares (including any shares received by the Executive with respect
                to the
                Restricted Shares as a result of stock dividends, stock splits or
                any
                other form of recapitalization) shall be subject to (1) customary
                restrictions on ownership and transfer set forth in the restricted
                stock
                agreement and (2) the vesting requirements set forth in this Section
                3(e);
                provided, however, that such vesting requirements shall be modified
                upon
                the termination of the Executive’s employment, other than in the event of
                Voluntary Termination or Termination for Cause, in accordance with
                Section
                9 of this Agreement.

            


    

     

    
      	 	
              ii.

            	
              Except
                as provided herein and in the restricted stock agreement, the Executive
                shall have all rights of a stockholders with respect to the Restricted
                Shares including the right to receive dividends or other distributions
                and
                the right to vote the Restricted Shares provided that any such dividends
                or other distributions shall be retained by the Company unless and
                until
                the Restricted Shares in respect of which such dividends or other
                distributions were paid shall have
                vested.

            


    

     

     

    
      
        
        

      

      
        4

        
          

        

      

      
        
        

      

    

     

     

    
      	 	
              iii.

            	
              During
                the period prior to the time that any particular Restricted Shares
                become
                vested and the restrictions thereon lapse, the Executive may not
                sell,
                transfer, pledge or otherwise encumber or dispose of the Restricted
                Shares
                and any attempted sale, transfer, pledge or other encumbrance or
                disposition (whether voluntary or involuntary) in violation of this
                Section shall be null and void. 

            


    

     

    
      	
            	iv.	
              The
                Compensation Committee shall appoint an executive officer of the
                Company
                or such other escrow holder who shall retain physical custody of
                the each
                certificate representing the Restricted Shares until the Restricted
                Shares
                have vested. Upon vesting of any Restricted Shares, the certificates
                evidencing such Restricted Shares shall be delivered promptly to
                the
                Executive. In the case of the Executive’s death, such certificates shall
                be delivered to the beneficiary designated in writing by the Executive
                pursuant to a form of designation provided by the Company, to the
                Executive’s legatee or to his personal representative as the case may be.
                Unless registered under the Securities Act of 1933, as amended,
                certificates evidencing the Restricted Shares shall bear the following
                legend: 

            


    

     

    THE
      SHARES EVIDENCED BY THIS CERTIFICATE MAY NOT BE SOLD, TRANSFERRED, PLEDGED,
      HYPOTHECATED OR OTHERWISE DISPOSED OF UNLESS REGISTERED UNDER THE SECURITIES
      ACT
      OF 1933, AS AMENDED, OR UNLESS, IN THE OPINION OF COUNSEL FOR THE COMPANY,
      SUCH
      REGISTRATION IS NOT REQUIRED.

     

    
      	
            	v.	
              The
                Company shall have the right, but not the obligation, to repurchase
                from
                the Executive, immediately upon the termination of the Executive’s
                employment if such termination is a Termination for Cause, such Restricted
                Shares as are vested on the date of termination at a cash price per
                share
                equal to the fair market value of such Restricted Shares on the date
                of
                termination.

            


    

     

    
      	 	
              vi.

            	
              Additional
                future grants of restricted stock awards may be made to the Executive
                at
                the discretion of the Compensation Committee.


            


    

     

    
      	 	
              f.

            	
              Vacation.
                The Executive shall be entitled to 30 days of vacation in each calendar
                year.

            


    

     

    
      	 	
              g.

            	
              Expenses.
                The Company shall reimburse the Executive in accordance with the
                practices
                in effect from time to time for other officers or staff personnel
                of the
                Company for all reasonable and necessary business and travel expenses
                and
                other disbursements incurred by the Executive for or on behalf of
                the
                Company in the performance of the Executive’s duties hereunder, upon
                presentation by the Executive to the Company of appropriate supporting
                documentation.

            


    

     

     

    
      
        
        

      

      
        5

        
          

        

      

      
        
        

      

    

     

     

    
      	 	
              h.

            	
              Certain
                Legal Expenses. The
                Company shall reimburse the Executive for the reasonable attorneys’ fees
                incurred by him in connection with the negotiation and preparation
                of this
                Agreement up to an aggregate of
                $10,000.

            


    

     

    
      	 	
              i.

            	
              Perquisites.
                The Executive shall be entitled to those perquisites as the Company
                shall
                make available from time to time to other executive officers of the
                Company, which shall include, without limitation, the costs associated
                with the use of an automobile in an amount not to exceed $1,000 per
                month
                and the costs for Executive’s use of a cellular telephone and personal
                digital assistant to the extent such equipment is used for business
                purposes.

            


    

     

    
      	
              4.

            	
              Death; Disability.
                In
                the event that the Executive dies or is incapacitated or disabled
                by
                accident, sickness or otherwise, so as to render the Executive mentally
                or
                physically incapable of performing the services required to be performed
                by the Executive under this Agreement for a period that would entitle
                the
                Executive to qualify for long-term disability benefits under the
                Company’s
                then-current long-term disability insurance program or, in the absence
                of
                such a program, for a period of 120 consecutive days or longer (such
                condition being herein referred to as a “Disability”)
                then (i) in the case of the Executive’s death, the Executive’s employment
                shall be deemed to terminate on the date of the Executive’s death and (ii)
                in the case of a Disability, the Company, at its option, may terminate
                the
                employment of the Executive under this Agreement immediately upon
                giving
                the Executive notice to that effect. The determination to terminate
                the
                Executive in the event of a Disability shall be made by the Board
                or the
                Board’s designee. In the case of a Disability, until the Company shall
                have terminated the Executive’s employment hereunder in accordance with
                the foregoing, the Executive shall be entitled to receive compensation
                provided for herein notwithstanding any such physical or mental
                disability. 

            


    

     

    
      	
              5.

            	
              Termination
                For Cause. The
                Company may terminate the employment of the Executive hereunder at
                any
                time during the Employment Period for “cause” (such termination being
                herein referred to as a “Termination
                for Cause”)
                by giving the Executive notice of such termination, which termination
                shall be effective on the date of such notice or such later date
                as may be
                specified by the Company. For purposes of this Agreement, “Cause”
                means (i) the Executive’s willful and substantial misconduct that is
                materially injurious to the Company and is either repeated after
                written
                notice from the Company specifying the misconduct or is continuing
                and not
                corrected within 20 days after written notice form the Company specifying
                the misconduct, (ii) the Executive’s repeated neglect of duties or failure
                to act which can reasonably be expected to affect materially and
                adversely
                the business or affairs of the Company after written notice from
                the
                Company specifying the neglect or failure to act, (iii) the Executive’s
                material breach of any of the agreements contained in Sections 11,
                12, 13
                or 14 hereof or of any of the Company’s policies, (iv) the commission by
                the Executive of any material fraudulent act with respect to the
                business
                and affairs of the Company, (v) the Executive’s conviction of (or plea of
                nolo contendere to) a crime constituting a felony, (vi) demonstrable
                gross
                negligence, or (vii) habitual insobriety or use of illegal drugs
                by the
                Executive while performing his duties under this Agreement which
                adversely
                affects the Executives performance of his duties under this
                Agreement.

            


    

     

     

    
      
        
        

      

      
        6

        
          

        

      

      
        
        

      

    

     

     

    
      	
              6.

            	
              Termination
                Without Cause.
                The Company may terminate the employment of the Executive hereunder
                at any
                time without “cause” or fail to extend this Agreement pursuant to the
                terms hereof (such termination being herein referred to as “Termination
                Without Cause”)
                by giving the Executive notice of such termination, upon the giving
                of
                which such termination shall take effect not later than 30 days from
                the
                date such notice is given. 

            


    

     

    
      	
              7.

            	
              Voluntary
                Termination by Executive.
                Any termination of the employment of the Executive by the Executive
                otherwise than as a result of death or Disability or for Good Reason
                (as
                defined below) (such termination being herein referred to as “Voluntary
                Termination”).
                A Voluntary Termination will be deemed to be effective immediately
                upon
                such termination.

            


    

     

    
      	
              8.

            	
              Termination
                by Executive for Good Reason. Any
                termination of the employment of the Executive by the Executive for
                Good
                Reason which shall be deemed to be equivalent to a Termination without
                Cause. For purposes of this Agreement “Good
                Reason”
                means (i) any material breach by the Company of any of its obligations
                under this Agreement, (ii) any material reduction in the Executive’s
                duties, authority or responsibilities without his consent, (iii)
                any
                assignment to the Executive of duties or responsibilities materially
                inconsistent with his position and duties contained in this Agreement
                without his consent, (iv) a relocation of the Company’s principal
                executive offices or the Company determination to require the Executive
                to
                be based anywhere other than within 25 miles of the location at which
                the
                Executive on the date hereof performs his duties; (v) the taking
                of any
                action by the Company which would deprive the Executive of any material
                benefit plan (including, without limitation, any medical, dental,
                disability or life insurance); or (vi) the failure by the Company
                to
                obtain the specific assumption of this Agreement by any successor
                or
                assignee of the Company or any person acquiring substantially all
                of the
                Company’s assets; provided, however, that the Executive may not terminate
                the Employment Period for Good Reason unless he first provides the
                Company
                with written notice specifying the Good Reason and providing the
                Company
                with 20 days in which to remedy the stated
                reason.

            


    

     

    
      	
              9.

            	
              Effect
                of Termination of Employment.


            


    

     

    
      	 	
              a.

            	
              Voluntary
                Termination; Termination For Cause.
                Upon the termination of the Executive’s employment as a result of his
                Voluntary Termination or a Termination For Cause, the Executive shall
                not
                have any further rights or claims against the Company under this
                Agreement
                except the right to receive (i) the unpaid portion of the base salary
                provided for in Section 3(a) hereof, computed on a pro rata basis
                to the
                date of termination, (ii) payment of his accrued but unpaid amounts
                and
                extension of applicable benefits in accordance with the terms of
                any
                incentive compensation, retirement, employee welfare or other employee
                benefit plans or programs of the Company in which the Executive is
                then
                participating in accordance with the terms of such plans or programs,
                and
                (iii) reimbursement for any expenses for which the Executive shall
                not
                have theretofore been reimbursed as provided in Section 3 hereof.
                In such
                event, the Initial Stock Option and shares of the Initial Restricted
                Stock
                Award to the extent not vested as of the date of termination shall
                be
                forfeited to the Company (without any further action on the part
                of the
                Company or the Executive) and the Executive shall have no further
                rights
                in such regard.

            


    

     

     

    
      
        
        

      

      
        7

        
          

        

      

      
        
        

      

    

     

     

    
      	 	
              b.

            	
              Termination
                Without Cause; Termination for Good Reason.
                Upon the termination of the Executive’s employment as a result of a
                Termination Without Cause or for Good Reason, the Executive shall
                not have
                any further rights or claims against the Company under this Agreement
                except the right to receive (i) the payments and other rights provided
                for
                in Section 9(a) hereof and (ii) severance payments in the form of
                a
                continuation of the Executive’s base salary as in effect immediately prior
                to such termination for a period of 12 months following the effective
                date
                of such termination. In such event, an amount of shares equal to
                up to 25%
                of the total aggregate amount of the Initial Stock Option and the
                Restricted Stock Award granted to the Executive shall become vested.
                The
                balance of such unvested Initial Stock Option and shares of the Initial
                Restricted Stock Award shall be forfeited to the Company (without
                further
                action on the part of the Company or the Executive) as of the date
                of
                termination and the Executive shall have no further rights with respect
                to
                such balance. To the extent that severance payments shall be payable
                under
                this Agreement such payments shall be in consideration for and only
                after
                the Executive executes a General Release containing terms reasonably
                satisfactory to the Company. 

            


    

     

    
      	 	
              c.

            	
              Death
                and Disability.
                Upon the termination of the Executive’s employment as a result of death or
                Disability, neither the Executive nor the Executive’s beneficiaries or
                estate shall have any further rights or claims against the Company
                under
                this Agreement except the right to receive the payments and other
                rights
                provided for in Section 9(a) hereof. In such event, an amount of
                shares
                equal to up to 25% of the total aggregate amount of the Initial Stock
                Option and the Restricted Stock Award granted to the Executive shall
                become vested. The balance of such unvested Initial Stock Option
                and
                shares of Initial Restricted Stock Award shall be forfeited to the
                Company
                (without further action on the part of the Company or the Executive)
                as of
                the date of termination and the Executive shall have no further rights
                with respect to such balance.

            


    

     

    
      	 	
              d.

            	
              Forfeiture
                of Rights.
                In
                the event that, subsequent to termination of employment hereunder,
                the
                Executive (i) breaches any of the provisions of Sections 11, 12,
                13 or 14
                hereof or (ii) makes or facilitates the making of any adverse public
                statements or disclosures with respect to the business or securities
                of
                the Company, all payments and benefits to which the Executive may
                otherwise have been entitled shall immediately terminate and be forfeited,
                and any portion of such amounts as may have been paid to the Executive
                shall forthwith be returned to the Company.


            


    

     

    
      	
              10.

            	
              Change
                in Control Provisions. 

            


    

     

    
      	 	
              a.

            	
              Effect
                of Termination Following Change in Control.
                In
                the event of a Change in Control during the Employment Period and
                a
                subsequent termination of the Executive’s employment, either by the
                Company as a consequence of the Change in Control or any other Termination
                Without Cause or by the Executive for Good Reason, then (i) Executive
                shall be entitled to receive (A) the payments and other rights provided
                in
                Section 9(b) of this Agreement and (B) the benefits and other rights
                provided in Section 10(a) of this Agreement; and (ii) the Initial
                Stock
                Option and shares of the Initial Restricted Stock Award held by the
                Executive and not then vested shall become immediately and fully
                vested as
                of the effective date of the
                termination.

            


    

    
       

      
        
          
          

        

        
          8

          
            

          

        

        
          
          

        

      

       

    

    
      	 	
              b.

            	
              Definition
                of Change in Control.
                For purposes of this Agreement, a “Change
                in Control”
                means and shall be deemed to have occurred upon: (i) an acquisition
                subsequent to the date hereof by any person, entity or group (within
                the
                meaning of Section 13(d)(3) or 14(d)(2) of the Securities Exchange
                Act of
                1934, as amended (the “Exchange
                Act”))
                (a “Person”),
                of beneficial ownership (within the meaning of Rule 13d-3 promulgated
                under the Exchange Act) of 30% or more of either (A) the then outstanding
                shares of common stock of the Company (“Common
                Stock”)
                or (B) the combined voting power of the then outstanding voting securities
                of the Company entitled to vote generally in the election of directors
                (the “Outstanding
                Company Voting Securities”);
                excluding, however, the following: (1) any acquisition directly from
                the
                Company, other than an acquisition by virtue of the exercise of a
                conversion privilege unless the security being so converted was itself
                acquired directly from the Company, (2) any acquisition by the Company
                and
                (3) any acquisition by an employee benefit plan (or related trust)
                sponsored or maintained by the Company; (ii) the approval by the
                stockholders of the Company of a merger, consolidation, reorganization
                or
                similar corporate transaction, whether or not the Company is the
                surviving
                corporation in such transaction, in which outstanding shares of Common
                Stock are converted into (A) shares of stock of another company,
                other
                than a conversion into shares of voting common stock of the successor
                corporation (or a holding company thereof) representing 80% of the
                voting
                power of all capital stock thereof outstanding immediately after
                the
                merger or consolidation or (B) other securities (of either the Company
                or
                another company) or cash or other property; (iii) the approval by
                stockholders of the Company of the issuance of shares of Common Stock
                in
                connection with a merger, consolidation, reorganization or similar
                corporate transaction in an amount in excess of 40% of the number
                of
                shares of Common Stock outstanding immediately prior to the consummation
                of such transaction; (iv) the approval by the stockholders of the
                Company
                of (A) the sale or other disposition of all or substantially all
                of the
                assets of the Company or (B) a complete liquidation or dissolution
                of the
                Company; or (v) the adoption by the Board of a resolution to the
                effect
                that any person has acquired effective control of the business and
                affairs
                of the Company. 

            


    

     

    
      	
              11.

            	
              Disclosure
                of Confidential Information. The
                Executive shall not, directly or indirectly, at any time during or
                after
                the Employment Period, disclose to any person, firm, corporation
                or other
                business entity, except as required by law, or use for any purpose
                except
                in the good faith performance of the Executive’s duties to the Company,
                any Confidential Information (as herein defined). For purposes of
                this
                Agreement, “Confidential
                Information”
                means all trade secrets and other non-public information of a business,
                financial , marketing, technical or other nature pertaining to the
                Company
                or any subsidiary, including information of others that the Company
                or any
                subsidiary has agreed to keep confidential; provided, however, that
                Confidential Information shall not include any information that has
                entered or enters the public domain (other than through breach of
                the
                Executive’s obligations under this Agreement) or which the Executive is
                required to disclose by law or legal process. Upon the Company’s request
                at any time, the Executive shall immediately deliver to the Company
                all
                materials in the Executive’s possession which contain Confidential
                Information.

            


    

     

     

    
      
        
        

      

      
        9

        
          

        

      

      
        
        

      

    

     

     

    
      	
              12.

            	
              Restrictive
                Covenant. 

            


    

     

    
      	 	
              a.

            	
              Term
                of Restrictive Covenant. The
                Executive hereby acknowledges and recognizes that, during the Employment
                Period, the Executive shall be privy to trade secrets and Confidential
                Information critical to the Company’s business and the Executive further
                acknowledges and recognizes that the Company would find it extremely
                difficult or impossible to replace the Executive and, accordingly,
                the
                Executive agrees that, in consideration of the benefits to be received
                by
                the Executive hereunder, the Executive shall not, from and after
                the date
                hereof, throughout the Employment Period, and for a period of 12
                months
                following the termination of the Employment Period (i) directly or
                indirectly engage in the development, production, marketing or sale
                of
                    products that compete (or, upon commercialization, would compete)
                with
                products of the Company being developed (so long as such development
                has
                not been abandoned), marketed or sold at the time of the termination
                of
                the Employment Period (such business or activity being herein referred
                to
                as a “Competing
                Business”)
                whether such engagement shall be as an officer, director, owner,
                employee,
                partner, affiliate or other participant in any Competing Business,
                (ii)
                assist others in engaging in any Competing Business in the manner
                described in the foregoing clause (i), or (iii) induce other employees
                of
                the Company or any subsidiary thereof to terminate their employment
                with
                the Company or any subsidiary thereof or engage in any Competing
                Business
                or hire any employees of the Company or any subsidiary unless such
                persons
                have not been employees of the Company for at least 12 months.
                

            


    

     

    
      	 	
              b.

            	
              Sufficient
                Consideration. The
                Executive understands that the foregoing restrictions may limit the
                ability of the Executive to earn a livelihood in a business similar
                to the
                business of the Company, but nevertheless believes that the Executive
                has
                received and shall receive sufficient consideration and other benefits,
                as
                an employee of the Company and as otherwise provided hereunder, to
                justify
                such restrictions which, in any event (given the education, skills
                and
                ability of the Executive), the Executive believes would not prevent
                the
                Executive from earning a living. 

            


    

     

    
      	
              13.

            	
              Non-Disparagement.
                The
                Executive shall not engage in conduct, through word, act, gesture
                or other
                means, or disclose any information to the public or any third party
                which
                (i) directly or indirectly discredits or disparages in whole or in
                part
                the company, its subsidiaries, divisions, affiliates and/or successors
                as
                well as the products and the respective officers, directors, stockholders
                and employees of each of them; (ii) is detrimental to the reputation,
                character or standing of these entities, their products or any of
                their
                respective officers, directors, stockholders and/or employees; or
                (iii)
                which generally reflects negatively on the management decisions,
                strategy
                or decision-making of these
                entities.

            


    

     

     

    
      
        
        

      

      
        10

        
          

        

      

      
        
        

      

    

     

     

    
      	
              14.

            	
              Company
                Right to Inventions. The
                Executive shall promptly disclose, grant and assign to the Company,
                for
                its sole use and benefit, any and all inventions, improvements, technical
                information and suggestions relating in any way to the business of
                the
                Company which the Executive may develop or acquire during the Employment
                Period (whether or not during usual working hours), together with
                all
                patent applications, letters patent, copyrights and reissues thereof
                that
                may at any time be granted for or upon any such invention, improvement
                or
                technical information. In connection therewith: (i) the Executive
                shall,
                without charge, but at the expense of the Company, promptly at all
                times
                hereafter execute and deliver such applications, assignments, descriptions
                and other instruments as may be necessary or proper in the opinion
                of the
                Company to vest title to any such inventions, improvements, technical
                information, patent applications, patents, copyrights or reissues
                thereof
                in the Company and to enable it to obtain and maintain the entire
                right
                and title thereto throughout the world, and (ii) the Executive shall
                render to the Company, at its expense (including a reasonable payment
                for
                the time involved in case the Executive is not then in its employ),
                all
                such assistance as it may require in the prosecution of applications
                for
                said patents, copyrights or reissues thereof, in the prosecution
                or
                defense of interferences which may be declared involving any said
                applications, patents or copyrights and in any litigation in which
                the
                Company may be involved relating to any such patents, inventions,
                improvements or technical information.


            


    

     

    
      	
              15.

            	
              Enforcement.
                It
                is the desire and intent of the parties hereto that the provisions
                of this
                Agreement be enforceable to the fullest extent permissible under
                the laws
                and public policies applied in each jurisdiction in which enforcement
                is
                sought. Accordingly, to the extent that a restriction contained in
                this
                Agreement is more restrictive than permitted by the laws of any
                jurisdiction where this Agreement may be subject to review and
                interpretation, the terms of such restriction, for the purpose only
                of the
                operation of such restriction in such jurisdiction, shall be the
                maximum
                restriction allowed by the laws of such jurisdiction and such restriction
                shall be deemed to have been revised accordingly herein.
                

            


    

     

    
      	
              16.

            	
              Remedies;
                Survival. 

            


    

     

    
      	 	
              a.

            	
              Injunctive
                Relief. The
                Executive acknowledges and understands that the provisions of the
                covenants contained in Sections 11, 12, 13 and 14 hereof, the violation
                of
                which cannot be accurately compensated for in damages by an action
                at law,
                are of crucial importance to the Company, and that the breach or
                threatened breach of the provisions of this Agreement would cause
                the
                Company irreparable harm. In the event of a breach or threatened
                breach by
                the Executive of the provisions of Sections 11, 12, 13 or 14 hereof,
                the
                Company shall be entitled to an injunction restraining the Executive
                from
                such breach. Nothing herein contained shall be construed as prohibiting
                the Company from pursuing any other remedies available for any breach
                or
                threatened breach of this Agreement.


            


    

     

     

    
      
        
        

      

      
        11

        
          

        

      

      
        
        

      

    

     

     

    
      	 	
              b.

            	
              Survival.
                Notwithstanding
                anything contained in this Agreement to the contrary, the provisions
                of
                the Sections 3, 9, and 11 through 17 hereof shall survive the expiration
                or earlier termination of this Agreement until, by their terms, such
                provisions are no longer operative.


            


    

     

    
      	
              17.

            	
              Notices.
                Notices and other communications hereunder shall be in writing and
                shall
                be delivered personally or sent by air courier or first class certified
                or
                registered mail, return receipt requested and postage prepaid, addressed
                as follows: 

            


    

     

    if
      to the
      Company prior to the Effective Date to: 

     

    Healthcare
      Acquisition Corp.

    2116
      Financial Center

    666
      Walnut Street

    Des
      Moines, Iowa 50309

    


    with
      a
      copy to:

    Ellenoff,
      Grossman & Schole, LLP

    370
      Lexington Avenue, 19th
      Floor

    New
      York,
      New York 10017

    Attention:
      Brian Daughney, Esq.


     

    if
      to the
      Company after the Effective Date to:

     

    PharmAthene,
      Inc.

    175
      Admiral Cochran Drive, Suite 101

    Annapolis,
      MD 21401

    


    with
      a
      copy to:

     

    McCarter
      & English, LLP

    Four
      Gateway Center

    100
      Mulberry Street

    Newark,
      New Jersey 07102

    Attention:
      Jeffrey Baumel, Esq.


     

    if
      to the
      Executive to:

     

    David
      P.
      Wright

     

    with
      a
      copy to :

     

    
      
        
        

      

      
        12

        
          

        

      

      
        
        

      

    

     

    All
      notices and other communications given to any party hereto in accordance with
      the provisions of this Agreement shall be deemed to have been given on the
      date
      of delivery, if personally delivered; on the business day after the date when
      sent, if sent by air courier; and on the third business day after the date
      when
      sent, if sent by mail, in each case addressed to such party as provided in
      this
      Section 16 or in accordance with the latest unrevoked direction from such party.
      

     

    
      	18.	
              Binding
                Agreement; Benefit.
                The provisions of this Agreement shall be binding upon, and shall
                inure to
                the benefit of, the respective heirs, legal representatives and successors
                of the parties hereto. 

            


    

     

    
      	19.	
              Governing
                Law; Jurisdiction. This
                Agreement shall be governed by, and construed and enforced in accordance
                with, the laws of the State of Maryland applicable
                to contract made and to be performed therein. Any action to enforce
                any of
                the provisions of this Agreement shall be brought in a court of the
                State
                of Maryland
                or in Federal court located within that State. The parties consent
                to the
                jurisdiction of such courts and to the service of process in any
                manner
                provided by Maryland law. Each party irrevocably waives any objection
                which it may now or hereafter have to the laying of the venue of
                any such
                suit, action or proceeding brought in such court and any claim that
                such
                suit, action or proceeding brought in such court has been brought
                in an
                inconvenient forum and agrees that service of process in accordance
                with
                the foregoing shall be deemed in every respect effective and valid
                personal service of process upon such party.


            


    

     

    
      	20.	
              Waiver
                of Breach.
                The waiver by either party of a breach of any provision of this Agreement

                by the other party must be in writing and shall not operate or be
                construed as a waiver of any subsequent breach by such other party.
                

            


    

     

    
      	21.	
              Entire
                Agreement; Amendments.
                This Agreement contains the entire agreement between the parties
                with
                respect to the subject matter hereof and supersedes all prior agreements
                or understandings among the parties with respect thereof. This Agreement
                may be amended only by an agreement in writing signed by the parties
                hereto. 

            


    

     

    
      	22.	
              Headings.
                The section headings contained in this Agreement are for reference
                purposes only and shall not affect in any way the meaning or
                interpretation of this Agreement. 

            


    

     

    
      	23.	
              Severability.
                Any provision of this Agreement that is prohibited or unenforceable
                in any
                jurisdiction shall, as to such jurisdiction, be ineffective to the
                extent
                of such prohibition or unenforceability without invalidating the
                remaining
                provisions hereof, and any such prohibition or unenforceability in
                any
                jurisdiction shall not invalidate or render unenforceable such provision
                in any other jurisdiction. 

            


    

     

    
      	24.	
              409A
                Compliance.
                The intent of the Executive and the company is that the severance
                and
                other benefits payable to the Executive under this Agreement not
                be deemed
                “deferred compensation” under, and shall otherwise comply with, Section
                409A of the Internal Revenue Code of 1986, as amended. The Executive
                and
                the Company agree to use reasonable best efforts to amend the terms
                of
                this Agreement from time to time as may be necessary to avoid the
                imposition of liability under Section 409A of the Code in any manner
                that
                does not materially alter the substantive rights and obligations
                of the
                parties hereunder.

            


    

     

     

    
      
        
        

      

      
        13

        
          

        

      

      
        
        

      

    

     

     

    
      	25.	
              Executive’s
                Acknowledgement. The
                Executive acknowledges (a) that he has had the opportunity to consult
                with
                independent counsel of his own choice concerning this Agreement and
                (b)
                that he has read and understands the Agreement, is fully aware of
                its
                legal effect and has entered into it freely based on his own
                judgment.

            


    

     

    
      	26.	
              Assignment.
                This
                Agreement is personal in its nature and the parties hereto shall
                not,
                without the consent of the other, assign or transfer this Agreement
                or any
                rights or obligations hereunder; provided, that the provisions hereof
                shall inure to the benefit of, and be binding upon, each successor
                of the
                Company, whether by merger, consolidation, transfer of all or
                substantially all of its assets or otherwise.


            


    

     

    
      	27.	
              Counterparts.
                This
                Agreement may be executed in two or more counterparts, each of which
                shall
                for all purposes constitute one agreement which is binding on all
                of the
                parties hereto.

            


    

     

     

    
      
        
        

      

      
        14

        
          

        

      

      
        
        

      

    


    IN
      WITNESS WHEREOF, the
      parties have duly executed this Agreement as of the date first above written.
      

     

     

    
      	 	 	EXECUTIVE
	 
 	 
 	 
 
	
            	
            	/s/ David P. Wright
	 	
              
David
              P. Wright
	 	HEALTHCARE ACQUISITION
              CORP.


    

     

    
      	 	 	 
	
            	By  
              	/s/ John Pappjohn
	 	
              
Name:
              John Pappajohn 
	 	
              Title:
                Chairman

            


    

     

     

    
      
        
        

      

      
        15