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                                                                   EXHIBIT 10.11


                              NON-NEGOTIABLE PROMISSORY NOTE


$220,572.00                                                       April 1, 1999


         FOR VALUE RECEIVED, the undersigned, Inhibitex. Inc., a Delaware
corporation, with its principal offices at 8995 Westside Parkway, Alpharetta,
Georgia 30004 (the "Maker"), promises to pay to the order of AtheroGenics,
Inc., a Georgia corporation (the "Holder"), the principal sum of Two Hundred
Twenty Thousand Five Hundred Seventy-Two and 00/100 Dollars ($220,572.00),
together with interest on so much thereof as is from time to time outstanding
and unpaid, from the date hereof until the principal sum is paid in full, at
the rate of seven percent (7%) per annum, with principal and accrued interest
being due and payable as follows.

1.       PAYMENTS. All payments due hereunder shall be made in lawful money of
         the United States of America at 8995 Westside Parkway, Alpharetta,
         Georgia 30004, or at such other place as Holder may designate in
         writing to the undersigned. Commencing on the date of this Note,
         interest shall accrue and be computed on the daily outstanding balance
         on a 360-day year simple interest basis. Principal and interest shall
         be due and payable monthly, in advance, in accordance with the
         amortization schedule, attached hereto as Attachment A and
         incorporated herein by this reference, commencing on April 1, 1999 and
         continuing on the first day of each month thereafter and including
         March 1, 2009, at which time all outstanding principal and accrued but
         unpaid interest will be due and payable in full.

2.       EVENT OF DEFAULT. An event of default shall be deemed to occur if
         Maker fails to make or cause to be made any payments required to be
         made under this Note when the same shall be due and payable and such
         default is not cured within three (3) days after Maker receives
         written notice thereof from Holder.

         REMEDIES. Upon the occurrence of an event of default, at the option of
         the Holder, the entire principal amount due hereunder, together with
         all accrued interest and any other amounts due hereunder, shall
         immediately become due and payable.

4.       PREPAYMENT. This Note may be prepaid in full or in part prior to
         maturity, without penalty or fee.

5.       WAIVER. Maker hereby waives diligence, presentment, protest and
         demand, notice of protest, dishonor, notice of dishonor and nonpayment
         of this Note, and expressly agrees that, without in any way affecting
         the liability of Maker, Holder may extend any date or the time for
         payment of sums due hereunder.

6.       CHOICE OF LAW. This Note shall be governed by and construed and
         enforced in accordance with the laws of the State of Georgia (without
         regard to its rules of conflicts of laws).

7.       COSTS OF COLLECTION. The Maker shall reimburse the Holder for all
         reasonable costs and expenses (including reasonable attorneys' fees)
         actually incurred by the Holder in enforcing or collecting, or
         attempting to enforce or collect, the obligations evidenced by this
         Note, whether or not suit is instituted.

8.       SEVERABILITY. Wherever possible, each provision of this Note shall be
         interpreted in such manner as to be effective and valid, but if any
         provision hereof shall be prohibited by law or be otherwise invalid,
         such provision shall be ineffective to the extent of such prohibition
         or invalidity, without invalidating the remainder of such provision or
         the remaining provisions of this Note.
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9.       ASSIGNMENT. This Note may not be transferred or assigned by Holder to
         any third party without the prior written permission of Maker.

10.      HEADINGS. The headings and titles used in this Note are intended
         solely for identification and not for any substantive purpose, and no
         heading or title shall in any way limit or extend the provisions
         hereof.

11.      LIMITATION OF INTEREST. Notwithstanding any provision herein to the
         contrary, the interest rate provided by this Note shall in no case
         exceed the rate allowable under any statute or law applicable to this
         transaction when appropriate consideration is given to borrowers or
         lenders of like character or classification. In the event the rate is
         determined to exceed the rate allowable under any statute or law
         applicable to this transaction, the interest rate shall be the maximum
         allowed by any such statute or law, and any amounts actually paid in
         excess thereof, shall be credited to principal.

         Time is of the essence of this note.


         IN WITNESS WHEREOF, this Note has been duly scaled, executed and
delivered the day and year first above written.

                                  "MAKER"

                                  INHIBITEX, INC.,
                                  a Delaware corporation



                                  By: /s/ William A. Johnston
                                     -------------------------------------
                                     Name: William A. Johnston
                                     Title: