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                                                                    EXHIBIT 10.2

                     FIRST AMENDMENT TO SUBLEASE AGREEMENT


     THIS FIRST AMENDMENT TO SUBLEASE AGREEMENT (this "Amendment") is made as of
the 1st day of February, 2000, by and between PREMIERE COMMUNICATIONS, INC.
("Sublandlord"), and HEALTHEON/WEBMD CORPORATION, successor by merger to
Endeavor Technologies, Inc. ("Subtenant").

                                  WITNESSETH

     WHEREAS, Sublandlord, by Agreement of Lease dated March 3, 1997 (the
"Master Lease"), leased from Corporate Property Investors (the "Landlord") the
entire fourth (4th) floor comprising 20,838 rentable square feet (the
"Premises") along with additional space on other floors, in the building
commonly known as The Lenox Building, located at 3399 Peachtree Road, N.E.,
Atlanta, Georgia as more particularly described in the Master Lease and the
Sublease (as hereinafter defined).

     WHEREAS, pursuant to that certain Sublease Agreement dated December 16,
1997, by and between Sublandlord and Subtenant (the "Sublease"), Subtenant
leased the Premises from Sublandlord;

     WHEREAS, pursuant to Paragraph 1 of the Sublease, the term of the Sublease
is scheduled to expire on February 1, 2000;

     WHEREAS, pursuant to Paragraph 21 of the Sublease, if Subtenant and
Sublandlord mutually agree and Landlord consents, Subtenant shall have the
option to renew the Sublease for one (1) additional one-year period under the
same terms and conditions as those of the Sublease, except that the Base Rent
(as defined in the Sublease) to be paid thereunder shall be adjusted upward by
the amount of increase under the Master Lease, if any;

     WHEREAS, Subtenant desires to extend the Sublease term for one (1)
additional two-year term and Sublandlord has agreed to such renewal, subject to
the consent of the Landlord;

     WHEREAS, Sublandlord and Subtenant desire to amend the Lease to provide for
the two-year extension pursuant to the terms and conditions as hereinafter set
forth.

     NOW, THEREFORE, in consideration of the mutual promises of the parties and
the mutual benefits to be derived by the performances of the parties hereunder;
and other good and valuable consideration, the receipt and sufficiency of which
is hereby acknowledged, the parties hereto agree as follows:

     1.  Recitals.  The above recitals are true and correct.
         --------

     2.  Extension of Sublease Term. The Sublease Term as defined in Paragraph 1
         --------------------------
of the Sublease is hereby extended for one (1) two-year period (the "Extension
Term"), commencing on the expiration date of the Sublease (the "Extension
Commencement Date") and
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ending on February 1, 2002 (the "Extension Expiration Date"). As of the
Extension Commencement Date, the Sublease is hereby amended so that any
reference therein to the "Sublease Term" shall be a reference to the Extension
Term and any reference therein to the "Expiration Date" shall be a reference to
the Extension Expiration Date.

     3.  Base Rent. The Base Rent for the Premises shall increase from $21.00
         ---------
per rentable square foot to $22.00 per rentable square foot (per year) as of
April 1, 2001, as set forth in the Master Lease.

     4.  Landlord's Consent Required. This Amendment is expressly conditioned
         ---------------------------
upon the written consent of the Landlord. Upon execution of this Amendment,
Sublandlord will promptly request such written consent. If such consent has not
been received by Sublandlord within thirty (30) days from the date hereof, then,
at the option of either party, upon written notice to the other at any time
after such 30-day period, this Amendment and the underlying Sublease shall be
deemed canceled, null and void, and of no further force and effect, and neither
party shall have any claim of any kind or nature against the other provided such
notice is sent before the Landlord's written consent is delivered to
Sublandlord.

     5.  Subtenant Improvements. Subtenant accepts the Premiere in their "as-is"
         ----------------------
condition for the Extension Term. Notwithstanding the foregoing, provided
Subtenant is not then in default under the Sublease, Sublandlord will install
new building standard carpet in the elevator lobby. Sublandlord's obligation to
install the carpet shall be subject to Landlord's approval.

     6.  Tenant's Estoppel.  Subtenant certifies to Sublandlord that:
         -----------------

         a.  the Sublease is presently in full force and effect and, as amended
and extended by this Amendment, represents the entire agreement between
Subtenant and Sublandlord with respect to the demised premises;

         b.  the Sublease has not been assigned and the demised premises have
not been sublet by Subtenant;

         c.  Subtenant intends to continue to occupy the demised premises on and
after the date of this Amendment;

         d.  To Subtenant's knowledge, Sublandlord is not in default under the
Sublease and no event has occurred which, with the giving of notice or passage
of time, or both, could result in a default by Sublandlord;

         e.  Subtenant has no existing defenses, offsets, liens, claims, or
credits against its payment obligations under the Sublease;

         f.  Subtenant has not received notice of violation of any federal,
state, county, or municipal laws, regulations, ordinances, orders, or directives
relating to the

                                       2
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use or condition of the demised premises; and

         g.  No Hazardous Substances have been disposed, stored, or treated on
or about the demised premises by Subtenant.

    7.  Miscellaneous.
        -------------
        a.  The Sublease shall continue in full force and effect in all other
respects not inconsistent with the express wording of this Amendment.

        b.  This Amendment may be executed in two or more of counterparts, each
of which shall constitute an original and all of which taken together shall
constitute one and the same instrument.

        c.  Captions and section headings appearing herein are included solely
for convenience of reference only and are not intended to affect the
interpretation of any provision of this Amendment.

        d.  This Amendment and the Sublease shall be governed by, and construed
in accordance with, the laws of the State of Georgia, without regard to
principles of conflict of laws.

        e.  Any term or provision of this Amendment or the Sublease which is
invalid or unenforceable in any jurisdiction shall, as to such jurisdiction, be
ineffective to the extent of such invalidity or unenforceability without
rendering invalid or unenforceable the remaining terms or provisions of this
Amendment or the Sublease or affecting the validity or enforceability of any of
the terms or provisions of this Amendment or the Sublease in any other
jurisdiction.


                     [SIGNATURES BEGIN ON FOLLOWING PAGE]

                                       3
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     IN WITNESS WHEREOF, the Sublandlord and the Subtenant have executed this
First Amendment to Sublease Agreement as of the day and year first above
written.


                                 SUBLANDLORD

                                 PREMIERE COMMUNICATION, INC.,
                                 a Florida corporation


                                 By: /s/ Patrick G. Jones
                                     -----------------------------------
                                 Print name: Patrick G. Jones
                                             ---------------------------
                                 Title: Executive Vice President
                                        --------------------------------

                                 SUBTENANT

                                 HEALTHEON/WEBMD CORPORATION,
                                 a Delaware corporation


                                 By: /s/ Jack Nichols
                                     -----------------------------------
                                 Print name: Jack Nichols
                                             ---------------------------
                                 Title: Vice President Asset Management
                                        --------------------------------

                                       4
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                              CONSENT OF LANDLORD

     Corporate Property Investors, as Landlord under the Master Lease, hereby
consents to the within First Amendment to Sublease Agreement by and between
Premiere Communications, Inc. and Endeavor Technologies, Inc. extending the
Sublease by Endeavor Technologies, Inc.  Corporate Property Investors further
acknowledges that any right to terminate the Master Lease by virtue of the
granting of this First Amendment to Sublease Agreement is hereby waived.


                                          LANDLORD:

                                          CORPORATE PROPERTY INVESTORS,
                                          a Massachusetts business trust


                                          By: /s/ Don Hession
                                              -------------------------------
                                          Print name: Don Hession
                                                      -----------------------
                                          Title:
                                                ----------------------------