sec document



                       SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549

                                 --------------

                                  SCHEDULE 13G
                                 (Rule 13d-102)

             INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT
           TO RULES 13d-1(b) (c) AND (d) AND AMENDMENTS THERETO FILED
                            PURSUANT TO RULE 13d-2(b)

                              (Amendment No. 2)(1)

                    Emergency Medical Services Corporation
--------------------------------------------------------------------------------
                               (Name of Issuer)

               CLASS A COMMON STOCK, PAR VALUE $0.01 PER SHARE
--------------------------------------------------------------------------------
                        (Title of Class of Securities)

                                  29100P102
--------------------------------------------------------------------------------
                                (CUSIP Number)

                              December 31, 2006
--------------------------------------------------------------------------------
           (Date of Event Which Requires Filing of this Statement)

                                 --------------

Check the  appropriate box to designate the rule pursuant to which this Schedule
is filed:

      /  /  Rule 13d-1(b)

      /x/   Rule 13d-1(c)

      /  /  Rule 13d-1(d)


--------------
      (1)   The remainder of this cover page shall be filled out for a reporting
person's  initial  filing on this  form with  respect  to the  subject  class of
securities,  and for any subsequent amendment containing information which would
alter the disclosures provided in a prior cover page.

            The  information  required in the remainder of this cover page shall
not be deemed to be "filed"  for the  purpose  of  Section 18 of the  Securities
Exchange Act of 1934 or otherwise  subject to the liabilities of that section of
the Act but shall be subject to all other  provisions of the Act  (however,  SEE
the NOTES).




----------------------                                    ----------------------
CUSIP No. 29100P102                   13D                    Page 2 of 17 Pages
----------------------                                    ----------------------


================================================================================
     1         NAME OF REPORTING PERSONS
               I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)

                    ACCIPITER LIFE SCIENCES FUND, LP
--------------------------------------------------------------------------------
     2         CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*         (a) / /
                                                                         (b) / /
--------------------------------------------------------------------------------
     3         SEC USE ONLY

--------------------------------------------------------------------------------
     4         CITIZENSHIP OR PLACE OF ORGANIZATION

                    DELAWARE
--------------------------------------------------------------------------------
 NUMBER OF         5     SOLE VOTING POWER
   SHARES
BENEFICIALLY                  60,081 shares
  OWNED BY     -----------------------------------------------------------------
    EACH           6     SHARED VOTING POWER
 REPORTING
PERSON WITH                   0 shares
               -----------------------------------------------------------------
                   7     SOLE DISPOSITIVE POWER

                              60,081 shares
               -----------------------------------------------------------------
                   8     SHARED DISPOSITIVE POWER

                              0 shares
--------------------------------------------------------------------------------
     9         AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING
               PERSON

                    60,081 shares
--------------------------------------------------------------------------------
    10         CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
               CERTAIN SHARES*                                               / /
--------------------------------------------------------------------------------
    11         PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

                    0.6%
--------------------------------------------------------------------------------
    12         TYPE OF REPORTING PERSON*

                    PN
================================================================================

                      *SEE INSTRUCTIONS BEFORE FILLING OUT!




----------------------                                    ----------------------
CUSIP No. 29100P102                   13D                    Page 3 of 17 Pages
----------------------                                    ----------------------


================================================================================
     1         NAME OF REPORTING PERSONS
               I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)

                    ACCIPITER LIFE SCIENCES FUND (OFFSHORE), LTD.
--------------------------------------------------------------------------------
     2         CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*         (a) / /
                                                                         (b) / /
--------------------------------------------------------------------------------
     3         SEC USE ONLY

--------------------------------------------------------------------------------
     4         CITIZENSHIP OR PLACE OF ORGANIZATION

                    CAYMAN ISLANDS
--------------------------------------------------------------------------------
 NUMBER OF         5     SOLE VOTING POWER
   SHARES
BENEFICIALLY                  60,226 shares
  OWNED BY     -----------------------------------------------------------------
    EACH           6     SHARED VOTING POWER
 REPORTING
PERSON WITH                   0 shares
               -----------------------------------------------------------------
                   7     SOLE DISPOSITIVE POWER

                              60,226 shares
               -----------------------------------------------------------------
                   8     SHARED DISPOSITIVE POWER

                              0 shares
--------------------------------------------------------------------------------
     9         AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING
               PERSON

                    60,226 shares
--------------------------------------------------------------------------------
    10         CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
               CERTAIN SHARES*                                               / /
--------------------------------------------------------------------------------
    11         PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

                    0.7%
--------------------------------------------------------------------------------
    12         TYPE OF REPORTING PERSON*

                    OO
================================================================================

                      *SEE INSTRUCTIONS BEFORE FILLING OUT!




----------------------                                    ----------------------
CUSIP No. 29100P102                   13D                    Page 4 of 17 Pages
----------------------                                    ----------------------


================================================================================
     1         NAME OF REPORTING PERSONS
               I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)

                    ACCIPITER LIFE SCIENCES FUND II, LP
--------------------------------------------------------------------------------
     2         CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*         (a) / /
                                                                         (b) / /
--------------------------------------------------------------------------------
     3         SEC USE ONLY

--------------------------------------------------------------------------------
     4         CITIZENSHIP OR PLACE OF ORGANIZATION

                    DELAWARE
--------------------------------------------------------------------------------
 NUMBER OF         5     SOLE VOTING POWER
   SHARES
BENEFICIALLY                  144,909 shares
  OWNED BY     -----------------------------------------------------------------
    EACH           6     SHARED VOTING POWER
 REPORTING
PERSON WITH                   0 shares
               -----------------------------------------------------------------
                   7     SOLE DISPOSITIVE POWER

                              144,909 shares
               -----------------------------------------------------------------
                   8     SHARED DISPOSITIVE POWER

                              0 shares
--------------------------------------------------------------------------------
     9         AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING
               PERSON

                    144,909 shares
--------------------------------------------------------------------------------
    10         CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
               CERTAIN SHARES*                                               / /
--------------------------------------------------------------------------------
    11         PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

                    1.6%
--------------------------------------------------------------------------------
    12         TYPE OF REPORTING PERSON*

                    PN
================================================================================

                      *SEE INSTRUCTIONS BEFORE FILLING OUT!




----------------------                                    ----------------------
CUSIP No. 29100P102                   13D                    Page 5 of 17 Pages
----------------------                                    ----------------------


================================================================================
     1         NAME OF REPORTING PERSONS
               I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)

                    ACCIPITER LIFE SCIENCES FUND II (OFFSHORE), LTD.
--------------------------------------------------------------------------------
     2         CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*         (a) / /
                                                                         (b) / /
--------------------------------------------------------------------------------
     3         SEC USE ONLY

--------------------------------------------------------------------------------
     4         CITIZENSHIP OR PLACE OF ORGANIZATION

                    CAYMAN ISLANDS
--------------------------------------------------------------------------------
 NUMBER OF         5     SOLE VOTING POWER
   SHARES
BENEFICIALLY                  264,614 shares
  OWNED BY     -----------------------------------------------------------------
    EACH           6     SHARED VOTING POWER
 REPORTING
PERSON WITH                   0 shares
               -----------------------------------------------------------------
                   7     SOLE DISPOSITIVE POWER

                              264,614 shares
               -----------------------------------------------------------------
                   8     SHARED DISPOSITIVE POWER

                              0 shares
--------------------------------------------------------------------------------
     9         AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING
               PERSON

                    264,614 shares
--------------------------------------------------------------------------------
    10         CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
               CERTAIN SHARES*                                               / /
--------------------------------------------------------------------------------
    11         PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

                    2.9%
--------------------------------------------------------------------------------
    12         TYPE OF REPORTING PERSON*

                    OO
================================================================================

                      *SEE INSTRUCTIONS BEFORE FILLING OUT!




----------------------                                    ----------------------
CUSIP No. 29100P102                   13D                    Page 6 of 17 Pages
----------------------                                    ----------------------


================================================================================
     1         NAME OF REPORTING PERSONS
               I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)

                    ACCIPITER LIFE SCIENCES FUND II (QP), LP
--------------------------------------------------------------------------------
     2         CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*         (a) / /
                                                                         (b) / /
--------------------------------------------------------------------------------
     3         SEC USE ONLY

--------------------------------------------------------------------------------
     4         CITIZENSHIP OR PLACE OF ORGANIZATION

                    DELAWARE
--------------------------------------------------------------------------------
 NUMBER OF         5     SOLE VOTING POWER
   SHARES
BENEFICIALLY                  146,029 shares
  OWNED BY     -----------------------------------------------------------------
    EACH           6     SHARED VOTING POWER
 REPORTING
PERSON WITH                   0 shares
               -----------------------------------------------------------------
                   7     SOLE DISPOSITIVE POWER

                              146,029 shares
               -----------------------------------------------------------------
                   8     SHARED DISPOSITIVE POWER

                              0 shares
--------------------------------------------------------------------------------
     9         AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING
               PERSON

                    146,029 shares
--------------------------------------------------------------------------------
    10         CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
               CERTAIN SHARES*                                               / /
--------------------------------------------------------------------------------
    11         PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

                    1.6%
--------------------------------------------------------------------------------
    12         TYPE OF REPORTING PERSON*

                    PN
================================================================================

                      *SEE INSTRUCTIONS BEFORE FILLING OUT!




----------------------                                    ----------------------
CUSIP No. 29100P102                   13D                    Page 7 of 17 Pages
----------------------                                    ----------------------


================================================================================
     1         NAME OF REPORTING PERSONS
               I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)

                    CANDENS CAPITAL, LLC
--------------------------------------------------------------------------------
     2         CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*         (a) / /
                                                                         (b) / /
--------------------------------------------------------------------------------
     3         SEC USE ONLY

--------------------------------------------------------------------------------
     4         CITIZENSHIP OR PLACE OF ORGANIZATION

                    DELAWARE
--------------------------------------------------------------------------------
 NUMBER OF         5     SOLE VOTING POWER
   SHARES
BENEFICIALLY                  0 shares
  OWNED BY     -----------------------------------------------------------------
    EACH           6     SHARED VOTING POWER
 REPORTING
PERSON WITH                   351,019 shares
               -----------------------------------------------------------------
                   7     SOLE DISPOSITIVE POWER

                              0 shares
               -----------------------------------------------------------------
                   8     SHARED DISPOSITIVE POWER

                              351,019 shares
--------------------------------------------------------------------------------
     9         AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING
               PERSON

                    351,019 shares
--------------------------------------------------------------------------------
    10         CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
               CERTAIN SHARES*                                               / /
--------------------------------------------------------------------------------
    11         PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

                    3.8%
--------------------------------------------------------------------------------
    12         TYPE OF REPORTING PERSON*

                    OO
================================================================================

                      *SEE INSTRUCTIONS BEFORE FILLING OUT!




----------------------                                    ----------------------
CUSIP No. 29100P102                   13D                    Page 8 of 17 Pages
----------------------                                    ----------------------


================================================================================
     1         NAME OF REPORTING PERSONS
               I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)

                    ACCIPITER CAPITAL MANAGEMENT, LLC
--------------------------------------------------------------------------------
     2         CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*         (a) / /
                                                                         (b) / /
--------------------------------------------------------------------------------
     3         SEC USE ONLY

--------------------------------------------------------------------------------
     4         CITIZENSHIP OR PLACE OF ORGANIZATION

                    DELAWARE
--------------------------------------------------------------------------------
 NUMBER OF         5     SOLE VOTING POWER
   SHARES
BENEFICIALLY                  0 shares
  OWNED BY     -----------------------------------------------------------------
    EACH           6     SHARED VOTING POWER
 REPORTING
PERSON WITH                   324,840 shares
               -----------------------------------------------------------------
                   7     SOLE DISPOSITIVE POWER

                              0 shares
               -----------------------------------------------------------------
                   8     SHARED DISPOSITIVE POWER

                              324,840 shares
--------------------------------------------------------------------------------
     9         AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING
               PERSON

                    324,840 shares
--------------------------------------------------------------------------------
    10         CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
               CERTAIN SHARES*                                               / /
--------------------------------------------------------------------------------
    11         PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

                    3.5%
--------------------------------------------------------------------------------
    12         TYPE OF REPORTING PERSON*

                    OO
================================================================================

                      *SEE INSTRUCTIONS BEFORE FILLING OUT!




----------------------                                    ----------------------
CUSIP No. 29100P102                   13D                    Page 9 of 17 Pages
----------------------                                    ----------------------


================================================================================
     1         NAME OF REPORTING PERSONS
               I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)

                    GABE HOFFMAN
--------------------------------------------------------------------------------
     2         CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*         (a) / /
                                                                         (b) / /
--------------------------------------------------------------------------------
     3         SEC USE ONLY

--------------------------------------------------------------------------------
     4         CITIZENSHIP OR PLACE OF ORGANIZATION

                    USA
--------------------------------------------------------------------------------
 NUMBER OF         5     SOLE VOTING POWER
   SHARES
BENEFICIALLY                  0 shares
  OWNED BY     -----------------------------------------------------------------
    EACH           6     SHARED VOTING POWER
 REPORTING
PERSON WITH                   675,859 shares
               -----------------------------------------------------------------
                   7     SOLE DISPOSITIVE POWER

                              0 shares
               -----------------------------------------------------------------
                   8     SHARED DISPOSITIVE POWER

                              675,859 shares
--------------------------------------------------------------------------------
     9         AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING
               PERSON

                    675,859 shares
--------------------------------------------------------------------------------
    10         CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
               CERTAIN SHARES*                                               / /
--------------------------------------------------------------------------------
    11         PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

                    7.3%
--------------------------------------------------------------------------------
    12         TYPE OF REPORTING PERSON*

                    IN
================================================================================

                      *SEE INSTRUCTIONS BEFORE FILLING OUT!




----------------------                                    ----------------------
CUSIP No. 29100P102                   13D                    Page 10 of 17 Pages
----------------------                                    ----------------------

Item 1(a).  Name of Issuer:

            Emergency Medical Services Corporation

Item 1(b).  Address of Issuer's Principal Executive Offices:

            6200 S. Syracuse Way
            Suite 200
            Greenwood Village, Colorado 80111

Item 2(a).  Name of Person Filing:

            This statement is jointly filed by Accipiter Life Sciences Fund, LP,
            a Delaware  limited  partnership  ("ALSF"),  Accipiter Life Sciences
            Fund  (Offshore),  Ltd.,  a  Cayman  Islands  company  ("Offshore"),
            Accipiter Life Sciences Fund II, LP, a Delaware limited  partnership
            ("ALSF II"),  Accipiter  Life Sciences Fund II  (Offshore),  Ltd., a
            Cayman Islands Company ("Offshore II"), Accipiter Life Sciences Fund
            II (QP), LP, a Delaware  limited  partnership  ("QP II"),  Accipiter
            Capital  Management,  LLC,  a  Delaware  limited  liability  company
            ("Management"),  Candens Capital,  LLC, a Delaware limited liability
            company  ("Candens") and Gabe Hoffman  (together with ALSF, ALSF II,
            Offshore, Offshore II, QP II, Management and Candens, the "Reporting
            Person").  Gabe  Hoffman is the  managing  member of  Candens  (Gabe
            Hoffman  and Candens are  hereinafter  referred to as the  "Domestic
            Controlling Persons"),  which in turn is the general partner of ALSF
            and ALSF II and QP II, and the managing  member of Management  (Gabe
            Hoffman and Management are  hereinafter  referred to as the "Foreign
            Controlling  Persons"),  which in turn is the investment  manager of
            Offshore and Offshore II.  Consequently,  Mr. Hoffman,  the Domestic
            Controlling  Persons and Foreign  Controlling Persons may be deemed,
            pursuant to Rule 13d-3 of the  Securities  Exchange Act of 1934,  as
            amended (the "Act"),  to be the  beneficial  owners of all shares of
            Class A Common Stock held by ALSF,  ALSF II,  Offshore,  Offshore II
            and QP II. The Reporting Persons are filing this joint statement, as
            they may be considered a "group" under Section  13(d)(3) of the Act.
            However,  neither this filing nor anything contained herein shall be
            deemed to be an admission by the Reporting Persons that such a group
            exists.

Item 2(b).  Address of Principal Business Office or, if None, Residence:

            399 Park Avenue, 38th Floor
            New York, New York 10022

Item 2(c).  Citizenship:

            ALSF, ALSF II, QP II, Candens and Management are organized under the
            laws  of  the  State  of  Delaware.  Offshore  and  Offshore  II are
            organized  under the laws of the Cayman  Islands.  Gabe Hoffman is a
            citizen of the United States of America.

Item 2(d).  Title of Class of Securities:

            Class A Common Stock, par value $0.01 per share




----------------------                                    ----------------------
CUSIP No. 29100P102                   13D                    Page 11 of 17 Pages
----------------------                                    ----------------------

Item 2(e).  CUSIP Number:

            29100P102

Item 3.     If This Statement is Filed Pursuant to Rule 13d-1(b), or 13d-2(b) or
            (c), Check Whether the Person Filing is a:

            /X/   Not Applicable

      (a)   / /   Broker or dealer  registered  under Section 15 of the Exchange
                  Act.

      (b)   / /   Bank as defined in Section 3(a)(6) of the Exchange Act.

      (c)   / /   Insurance  company  as  defined  in  Section  3(a)(19)  of the
                  Exchange Act.

      (d)   / /   Investment   company   registered   under  Section  8  of  the
                  Investment Company Act.

      (e)   /  /  An    investment    adviser    in    accordance    with   Rule
                  13d-1(b)(1)(ii)(E).

      (f)   / /   An employee  benefit plan or endowment fund in accordance with
                  Rule 13d-1(b)(1)(ii)(F).

      (g)   / /   A parent holding  company or control person in accordance with
                  Rule 13d-1(b)(1)(ii)(G).

      (h)   / /   A  savings  association  as  defined  in  Section  3(b) of the
                  Federal Deposit Insurance Act.

      (i)   / /   A church  plan  that is  excluded  from the  definition  of an
                  investment  company under Section  3(c)(14) of the  Investment
                  Company Act.

      (j)   / /   Group, in accordance with Rule 13d-1(b)(1)(ii)(J).

Item 4.     Ownership

            The percentages used herein are calculated based on 9,262,853 shares
            of  Class A Common  Stock  outstanding  as of  November  1,  2006 as
            reported in the  Issuer's  quarterly  report on Form 10-Q filed with
            the Securities and Exchange Commission on November 7, 2006.

            See Cover Pages, Items 5-11.

Item 5.     Ownership of Five Percent or Less of a Class.

            If this  statement  is being filed to report the fact that as of the
date hereof the reporting  person has ceased to be the beneficial  owner of more
than five percent of the class of securities, check the following [].




----------------------                                    ----------------------
CUSIP No. 29100P102                   13D                    Page 12 of 17 Pages
----------------------                                    ----------------------


Item 6.     Ownership of More than Five Percent on Behalf of Another Person.

            Not Applicable


Item 7.     Identification and Classification of the Subsidiary Which
            Acquired the Security Being Reported on by the Parent Holding
            Company or Control Person.

            Not Applicable

Item 8.     Identification and Classification of Members of the Group.

            See Exhibit A.

Item 9.     Notice of Dissolution of Group.

            Not Applicable

Item 10.    Certifications.

            By signing  below I certify  that,  to the best of my knowledge  and
belief, the securities  referred to above were not acquired and are not held for
the purpose of or with the effect of changing or influencing  the control of the
issuer of the  securities  and were not acquired and are not held in  connection
with or as a participant in any transaction having that purpose or effect.




----------------------                                    ----------------------
CUSIP No. 29100P102                   13D                    Page 13 of 17 Pages
----------------------                                    ----------------------


                                    SIGNATURE
                                    ---------

            After reasonable inquiry and to the best of my knowledge and belief,
I certify that the information set forth in this statement is true, complete and
correct.

Dated: January 18, 2007                  ACCIPITER LIFE SCIENCES FUND, LP

                                         By: Candens Capital, LLC
                                             its general partner

                                         By: /s/ Gabe Hoffman
                                             -----------------------------------
                                             Gabe Hoffman, Managing Member


                                         ACCIPITER LIFE SCIENCES FUND II, LP

                                         By: Candens Capital, LLC
                                             its general partner

                                         By: /s/ Gabe Hoffman
                                             -----------------------------------
                                             Gabe Hoffman, Managing Member


                                         ACCIPITER LIFE SCIENCES FUND
                                         (OFFSHORE), LTD.

                                         By: Accipiter Capital Management, LLC
                                             its investment manager

                                         By: /s/ Gabe Hoffman
                                             -----------------------------------
                                             Gabe Hoffman, Managing Member


                                         ACCIPITER LIFE SCIENCES FUND II
                                         (OFFSHORE), LTD.

                                         By: Accipiter Capital Management, LLC
                                             its investment manager

                                         By: /s/ Gabe Hoffman
                                             -----------------------------------
                                             Gabe Hoffman, Managing Member




----------------------                                    ----------------------
CUSIP No. 29100P102                   13D                    Page 14 of 17 Pages
----------------------                                    ----------------------


                                         ACCIPITER LIFE SCIENCES FUND II (QP),
                                         LP

                                         By: Candens Capital, LLC
                                             its general partner

                                         By: /s/ Gabe Hoffman
                                             -----------------------------------
                                             Gabe Hoffman, Managing Member


                                         ACCIPITER CAPITAL MANAGEMENT, LLC

                                         By: /s/ Gabe Hoffman
                                             -----------------------------------
                                             Gabe Hoffman, Managing Member


                                         CANDENS CAPITAL, LLC

                                         By: /s/ Gabe Hoffman
                                             -----------------------------------
                                             Gabe Hoffman, Managing Member


                                         /s/ Gabe Hoffman
                                         ----------------------------------------
                                         GABE HOFFMAN




----------------------                                    ----------------------
CUSIP No. 29100P102                   13D                    Page 15 of 17 Pages
----------------------                                    ----------------------


                                  EXHIBIT INDEX

            The following document is filed herewith:

            (a)   Joint  Filing  Agreement  dated as of January  18,  2007 among
                  Accipiter Life Sciences Fund, LP, Accipiter Life Sciences Fund
                  II,  LP,  Accipiter  Life  Sciences  Fund  (Offshore),   Ltd.,
                  Accipiter  Life Sciences Fund II (Offshore),  Ltd.,  Accipiter
                  Life Sciences Fund II (QP), LP, Accipiter Capital  Management,
                  LLC, Candens Capital, LLC and Gabe Hoffman.




----------------------                                    ----------------------
CUSIP No. 29100P102                   13D                    Page 16 of 17 Pages
----------------------                                    ----------------------


                                    EXHIBIT A

                             JOINT FILING AGREEMENT
                             ----------------------

      The  undersigned  hereby  agree that the  Statement  on Schedule 13G dated
January 18, 2007 with respect to the shares of Common Stock of Emergency Medical
Services Corporation and any further amendments thereto executed by each and any
of the undersigned shall be filed on behalf of each of the undersigned  pursuant
to and  in  accordance  with  the  provisions  of  Rule  13d-1(k)(1)  under  the
Securities Exchange Act of 1934, as amended.

Dated: January 18, 2007                  ACCIPITER LIFE SCIENCES FUND, LP

                                         By: Candens Capital, LLC
                                             its general partner

                                         By: /s/ Gabe Hoffman
                                             -----------------------------------
                                             Gabe Hoffman, Managing Member


                                         ACCIPITER LIFE SCIENCES FUND II, LP

                                         By: Candens Capital, LLC
                                             its general partner

                                         By: /s/ Gabe Hoffman
                                             -----------------------------------
                                             Gabe Hoffman, Managing Member


                                         ACCIPITER LIFE SCIENCES FUND
                                         (OFFSHORE), LTD.

                                         By: Accipiter Capital Management, LLC
                                             its investment manager

                                         By: /s/ Gabe Hoffman
                                             -----------------------------------
                                             Gabe Hoffman, Managing Member


                                         ACCIPITER LIFE SCIENCES FUND II
                                         (OFFSHORE), LTD.

                                         By: Accipiter Capital Management, LLC
                                             its investment manager

                                         By: /s/ Gabe Hoffman
                                             -----------------------------------
                                             Gabe Hoffman, Managing Member




----------------------                                    ----------------------
CUSIP No. 29100P102                   13D                    Page 17 of 17 Pages
----------------------                                    ----------------------


                                         ACCIPITER LIFE SCIENCES FUND II (QP),
                                         LP

                                         By: Candens Capital, LLC
                                             its general partner

                                         By: /s/ Gabe Hoffman
                                             -----------------------------------
                                             Gabe Hoffman, Managing Member


                                         ACCIPITER CAPITAL MANAGEMENT, LLC

                                         By: /s/ Gabe Hoffman
                                             -----------------------------------
                                             Gabe Hoffman, Managing Member


                                         CANDENS CAPITAL, LLC

                                         By: /s/ Gabe Hoffman
                                             -----------------------------------
                                             Gabe Hoffman, Managing Member


                                         /s/ Gabe Hoffman
                                         ----------------------------------------
                                         GABE HOFFMAN