AMENDMENT NO. 1

                                       TO

                             UNDERWRITING AGREEMENT

            This Amendment No. 1 (the "Amendment") to the Underwriting Agreement
(the  "Agreement")  dated  July 28,  2005,  is made as of March 20,  2006 by and
between HEALTHCARE ACQUISITION CORP. (the "Corporation") and MAXIM GROUP LLC, as
representative of the underwriters (the "Representative"). Any terms used herein
but not defined shall have the meaning set forth in the Agreement.

            WHEREAS, the Corporation and the Representative desire to enter into
this  Amendment  to  clarify  the   enforceability  of  certain  provisions  the
Corporation's amended and restated charter (the "Charter");

            NOW,  THEREFORE,  in consideration of the mutual  agreements  herein
contained, the parties hereto agree as follows:

            1. The following  provisions  (A) through (E) shall apply during the
period   commencing  from  the  filing  of  Charter  and  terminating  upon  the
consummation of any "Business Combination",  and may not be amended prior to the
consummation of any Business  Combination.  A "Business  Combination" shall mean
the acquisition by the Corporation,  whether by merger,  capital stock exchange,
asset or stock acquisition or other similar type of transaction, of assets or an
operating business in the healthcare industry ("Target Business").

            A.  Prior  to the  consummation  of any  Business  Combination,  the
Corporation  shall submit such  Business  Combination  to its  stockholders  for
approval  regardless  of whether  the  Business  Combination  is of a type which
normally  would require such  stockholder  approval  under the GCL. In the event
that a majority of the IPO Shares (defined below) cast at the meeting to approve
the  Business   Combination   are  voted  for  the  approval  of  such  Business
Combination,  the  Corporation  shall be authorized  to consummate  the Business
Combination;  provided that the  Corporation  shall not  consummate any Business
Combination  if 20% or more in interest  of the  holders of IPO Shares  exercise
their conversion rights described in paragraph B below.

            B.  In  the  event  that  a  Business  Combination  is  approved  in
accordance with the above paragraph A and is consummated by the Corporation, any
stockholder  of the  Corporation  holding  shares of Common Stock ("IPO Shares")
issued in the  Corporation's  initial public offering  ("IPO") of securities who
voted  against the Business  Combination  may,  contemporaneous  with such vote,
demand that the  Corporation  convert his IPO Shares into cash.  If so demanded,
the Corporation  shall convert such shares at a per share conversion price equal
to the  quotient  determined  by  dividing  (i) the amount in the Trust Fund (as
defined below), inclusive of any interest thereon, calculated as of two business
days prior to the proposed consummation of the Business Combination, by (ii) the
total  number  of  IPO  Shares.  "Trust  Fund"  shall  mean  the  trust  account
established by the  Corporation at the  consummation of its IPO and into which a
certain amount of the net proceeds of the IPO are deposited.

            C. In the event that the Corporation  does not consummate a Business
Combination by the later of (i) 18 months after the  consummation  of the IPO or
(ii) 24 months  after the  consummation  of the IPO in the event  that  either a
letter of intent,  an  agreement  in  principle  or a  definitive  agreement  to
complete a Business Combination was executed but was not consummated within such
18 month period (such later date being referred to as the  "Termination  Date"),
the officers of the Corporation shall take all such action necessary to dissolve
and liquidate the  Corporation as soon as reasonably  practicable.  In the event
that the  Corporation  is so dissolved and  liquidated,  only the holders of IPO
Shares (at such time) shall be entitled to receive liquidating distributions and
the Corporation shall pay no liquidating distributions with respect to any other
shares of capital stock of the Corporation.




            D. A holder of IPO Shares shall be entitled to receive distributions
from the Trust Fund only in the event of a liquidation of the  Corporation or in
the event he demands  conversion of his shares in accordance  with  paragraph B,
above. In no other  circumstances shall a holder of IPO Shares have any right or
interest of any kind in or to the Trust Fund.

            E. The Board of Directors shall be divided into two classes: Class A
and Class B. The number of  directors  in each class shall be as nearly equal as
possible.  Prior to the IPO,  there shall be elected two Class A directors for a
term expiring at the  Corporation's  first Annual  Meeting of  Stockholders  and
three Class B directors for a term expiring at the  Corporation's  second Annual
Meeting of Stockholders. Commencing at the first Annual Meeting of Stockholders,
and at each  annual  meeting  thereafter,  directors  elected to  succeed  those
directors  whose terms expire shall be elected for a term of office to expire at
the second  succeeding  annual  meeting of  stockholders  after their  election.
Except as the GCL may otherwise require,  in the interim between annual meetings
of stockholders or special  meetings of stockholders  called for the election of
directors  and/or the  removal of one or more  directors  and the filling of any
vacancy in that connection, newly created directorships and any vacancies in the
Board of Directors,  including unfilled vacancies  resulting from the removal of
directors  for cause,  may be filled by the vote of a majority of the  remaining
directors  then in  office,  although  less  than a quorum  (as  defined  in the
Corporation's  Bylaws), or by the sole remaining  director.  All directors shall
hold office until the expiration of their  respective  terms of office and until
their  successors  shall have been elected and qualified.  A director elected to
fill a vacancy  resulting  from the death,  resignation or removal of a director
shall serve for the  remainder  of the full term of the  director  whose  death,
resignation  or removal  shall have created such vacancy and until his successor
shall have been elected and qualified.

            2. The  Corporation  acknowledges  that the  purchasers  of the Firm
Units and the Option  Units in the  Offering  shall be deemed to be third  party
beneficiaries of this Amendment.

            3. The Representative  and the Corporation  specifically agree that,
except  pursuant  to its own terms,  this  Amendment  shall not be  modified  or
amended in any way.

            4.  Terms  used  herein  but  not  defined  herein  shall  have  the
definitions set forth in the Agreement or the Charter, as applicable.

            The Agreement shall otherwise remain in full force and effect.



                  [remainder of page intentionally left blank]





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


                                   HEALTHCARE ACQUISITION CORP.


                                   By:  /s/  Matthew P. Kinley
                                        -------------------------------------
                                        Name: Matthew P. Kinley
                                        Title:  President



                                   MAXIM GROUP, LLC, as Representative


                                   By:  /s/ Clifford Teller
                                        -------------------------------------
                                        Name: Clifford Teller
                                        Title: Director of Investment Banking