<DOCUMENT>
<TYPE>8-K
<SEQUENCE>1
<FILENAME>h09521e8vk.txt
<DESCRIPTION>ENCYSIVE PHARMACEUTICALS INC.- OCTOBER 9, 2003
<TEXT>
<PAGE>
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549


                                    FORM 8-K


                                 CURRENT REPORT

                       Pursuant to Section 13 or 15 (d) of
                       the Securities Exchange Act of 1934


        Date of Report (Date of earliest event reported): October 9, 2003


                          ENCYSIVE PHARMACEUTICALS INC.
             (Exact name of registrant as specified in its charter)


<Table>
<S>                       <C>                        <C>
        DELAWARE                  0-20117                       13-3532643
(State of Incorporation)  (Commission File Number)   (IRS Employer Identification No.)
--------------------------------------------------------------------------------------
</Table>


                            6700 WEST LOOP, 4TH FLOOR
                              BELLAIRE, TEXAS 77401
              (Address of Registrant's principal executive offices)

                                 (713) 796-8822
              (Registrant's telephone number, including area code)


                                 Not Applicable
          (Former name or former address, if changed since last report)


<PAGE>


ITEM 7. FINANCIAL STATEMENTS, PRO FORMA FINANCIAL INFORMATION AND EXHIBITS.

              (c) Exhibits.

                  99.1     Press Release.

ITEM 9. REGULATION FD DISCLOSURE

              On October 9, 2003, Encysive Pharmaceuticals Inc. ("ENCY") issued
a press release regarding its majority-owned affiliate, Revotar
Biopharmaceuticals AG, initiating two phase IIa clinical trials in psoriasis and
atopic dermatitis. The full text of ENCY's press release is furnished herewith
as Exhibit 99.1.


                            [SIGNATURE PAGE FOLLOWS]


<PAGE>


                                    SIGNATURE

         Pursuant to the requirements of the Securities Exchange Act of 1934,
the registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.

                                 ENCYSIVE PHARMACEUTICALS INC.


Date: October 9, 2003            By: /s/ Stephen L. Mueller
                                     -------------------------------------------
                                     Stephen L. Mueller
                                     Vice-President, Finance and Administration
                                     Secretary and Treasurer


<PAGE>

                               INDEX TO EXHIBITS

<Table>
<Caption>
EXHIBIT
NUMBER             DESCRIPTION
-------            -----------
<S>                <C>
 99.1              Press Release.
</Table>

</TEXT>
</DOCUMENT>