Filed by Sanofi-Synthelabo
                                  Pursuant to Rule 165 and Rule 425(a) under the
                                United States Securities Act of 1933, as amended

                                                        Subject Company: Aventis
                                                   Commission File No. 001-10378
                                                               Date: May 4, 2004


         On May 4, 2004, Sanofi-Synthelabo issued the following press release.

         In connection with the proposed acquisition of Aventis,
Sanofi-Synthelabo has filed with the United States Securities and Exchange
Commission (SEC), a registration statement on Form F-4 (File no: 333-112314),
which includes a prospectus/offer to exchange and related exchange offer
materials, to register the Sanofi-Synthelabo ordinary shares (including
Sanofi-Synthelabo ordinary shares represented by Sanofi-Synthelabo ADSs) to be
issued in exchange for Aventis ordinary shares held by holders located in the
United States and for Aventis ADSs held by holders wherever located and has also
filed with the SEC a Statement on Schedule TO. INVESTORS AND HOLDERS OF AVENTIS
SECURITIES ARE STRONGLY ADVISED TO READ THE REGISTRATION STATEMENT AND THE
PROSPECTUS/OFFER TO EXCHANGE, THE RELATED EXCHANGE OFFER MATERIALS AND THE
STATEMENT ON SCHEDULE TO, AND ANY OTHER RELEVANT DOCUMENTS FILED WITH THE SEC,
AS WELL AS ANY AMENDMENTS AND SUPPLEMENTS (INCLUDING ANY SUPPLEMENT RELATING TO
SANOFI-SYNTHELABO'S REVISED OFFER), BECAUSE THEY CONTAIN IMPORTANT INFORMATION.
Investors and holders of Aventis securities may obtain free copies of the
registration statement, the prospectus/offer to exchange and related exchange
offer materials, and the Statement on Schedule TO, as well as other relevant
documents filed with the SEC, at the SEC's web site at www.sec.gov. The
prospectus/offer to exchange and other transaction-related documents are being
mailed to Aventis securityholders eligible to participate in the U.S. offer and
additional copies may be obtained for free from MacKenzie Partners, Inc., the
information agent for the U.S. offer, at the following address: 105, Madison
Avenue, New York, New York 10016; telephone 1-(212) 929-5500 (call collect) or
1-(800) 322-2885 (toll-free call); e-mail proxy@mackenziepartners.com. In
connection with its revised offer, Sanofi-Synthelabo intends to distribute a
supplement to the prospectus/offer to exchange as soon as practicable.


                                     * * * *

                                                        [Sanofi-Synthelabo Logo]


 Investor Relations

                                                              Paris, May 4, 2004




        POSTPONEMENT OF SANOFI-SYNTHELABO GENERAL MEETING OF MAY 24, 2004




The Board of Directors of Sanofi-Synthelabo, at its meeting of May 3, 2004,
decided to postpone the Combined Annual General Meeting of shareholders,
originally scheduled for May 24, 2004 (as announced in the "BALO" on April 19,
2004). The new date must be at least five trading days before the closing date
of Sanofi-Synthelabo's offer for Aventis, which will be set by the Autorite des
Marches Financiers (AMF).

This postponement is pursuant to the agreement reached with Aventis on April 25,
2004 relating to Sanofi-Synthelabo's offer for Aventis. A future meeting of the
Board of Directors will set a new date and agenda for the General Meeting, which
will be held to vote not only on the agenda for the Combined Annual General
Meeting, but also on the resolutions relating to the offer, including the
capital increase required for the shares to be issued in consideration for the
offer.

This postponement does not affect the proposed arrangements for the payment of
the 2003 dividend to Sanofi-Synthelabo shareholders: payment of an interim
dividend of 0.97 euros on May 5, 2004, with the balance to be paid on settlement
of the offer (the total amount of dividend proposed to the General Meeting of
Sanofi-Synthelabo shareholders remaining unchanged at 1.02 euros).


In accordance with article 7 of the COB rule no. 2002-04, this document was
transmitted to the Autorite des marches financiers (AMF) before its publication.

IMPORTANT INFORMATION: In connection with the proposed acquisition of Aventis,
Sanofi-Synthelabo has filed a registration statement on Form F-4 (File no.
333-112314) , including a prospectus/offer to exchange, and will file additional
documents with the United States Securities and Exchange Commission (SEC)
INVESTORS ARE URGED TO READ THE REGISTRATION STATEMENT, INCLUDING THE
PROSPECTUS/OFFER TO EXCHANGE, AND ANY OTHER RELEVANT DOCUMENTS FILED WITH THE
SEC, INCLUDING ALL AMENDMENTS AND SUPPLEMENTS (INCLUDING ANY SUPPLEMENT RELATING
TO ITS REVISED OFFERS), BECAUSE THEY CONTAIN IMPORTANT INFORMATION. Free copies
of the registration statement, as well as other relevant documents filed with
the SEC, may be obtained at the SEC's web site at www.sec.gov. The
prospectus/offer to exchange and other transaction-related documents are being
mailed to Aventis securityholders eligible to participate in the U.S. offer and
additional copies may be obtained for free from MacKenzie Partners, Inc., the
information agent for the U.S. offer, at the following address: 105, Madison
Avenue, New York, New York 10016; telephone 1-(212) 929-5500 (call collect) or
1-(800) 322-2885 (toll-free call); e-mail proxy@mackenziepartners.com. In
connection with its revised offer, Sanofi-Synthelabo intends to distribute a
supplement to the prospectus/offer to exchange as soon as practicable.

In France, holders of Aventis securities are requested, with respect to the
offer, to refer to the prospectus (NOTE D'INFORMATION), which has been granted
VISA number 04-0090 by the AMF and which is available on the website of the AMF
(www.amf-france.org) and without cost from: BNP Paribas Securities Services,
GIS-Emetteurs, Service Logistique, Les Collines de l'Arche, 75450 Paris Cedex 9
and to all other appropriate documents relating to the French offer filed with
the AMF.



The public offer to holders of Aventis ordinary shares located in Germany (the
"German Offer") is being made in accordance with applicable German law and
pursuant to an offer document/sales prospectus, which is available free of
charge at BNP Paribas Securities Services, Gruneburgweg 14, D-60322 Frankfurt am
Main (Fax: 069 - 152 05 277) and on the website of the Company
(www.sanofi-synthelabo.com). Any decision to tender Aventis ordinary shares in
exchange for Sanofi-Synthelabo ordinary shares under the German Offer must be
taken exclusively with regard to the terms and conditions of the German Offer,
as well as with regard to the information included in the offer document/sales
prospectus, including any amendments thereto, issued in Germany.

The French Offer, the U.S. Offer and the German Offer are being made on
substantially the same terms and completion of these offers is subject to the
same conditions. It is intended that the three offers will expire at the same
time.

Investors and security holders may obtain a free copy of the Form 20-F filed
with the SEC on April 2, 2004 and any other documents filed by Sanofi-Synthelabo
with the SEC at www.sec.gov as well as of the Reference Document filed with the
AMF on April 2, 2004 (No. 04-0391) at www.amf-france.org or directly from
Sanofi-Synthelabo on our web site at: www.sanofi-synthelabo.com.




INVESTOR RELATIONS DEPARTMENT
Phillipe Goupit         Director of Investor Relations
Arnaud Delepine         Investor Relations Europe
Sanjay Gupta            Investor Relations US
Anne d'Halluin-Sulzer   Investor Relations

CONTACTS:
E-mail: investor-relations@sanofi-synthelabo.com
Europe                          US
Tel: + 33 1 53 77 45 45         Tel.:  +1 212 551 42 93
Fax: + 33 1 53 77 42 96         Fax:   +1 212 551 49 92