UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

REPORT OF FOREIGN PRIVATE ISSUER
PURSUANT TO RULE 13a-16 OR 15d-16
UNDER THE SECURITIES EXCHANGE ACT OF 1934

Commission File Number: 001-31368

SANOFI-SYNTHÉLABO

174, avenue de France, 75013 Paris, FRANCE
(Address of principal executive offices)

Yes  o                               No  x

     Investor Relations

Alfuzosin 10 mg OD (Xatral® OD) shows beneficial effect in
patients with acute urinary retention
Need for BPH-related surgery reduced

Vienna, March 25, 2004 - The results of the ALFAUR (ALFuzosin in Acute Urinary Retention) study, announced today at the XIXth European Association of Urology (EAU) Congress in Vienna, Austria, indicate that the uroselective alpha₁-blocker alfuzosin 10 mg once daily (OD) may have a beneficial effect in the management of male patients suffering from acute urinary retention (AUR), a sudden inability to pass urine that results in a painful distension of the bladder, requires immediate management with urethral catheterization and could necessitate surgical intervention.

ALFAUR was a double-blind, placebo-controlled trial including 363 patients with a first episode of AUR related to benign prostatic hyperplasia (BPH).

The ALFAUR trial was conducted in two phases.
In the first phase of the study patients were randomised to receive alfuzosin 10 mg OD or placebo for a period of 2 to 3 days from the beginning of catheterization to a trial without catheter (TWOC). In this phase of the trial, alfuzosin 10 mg OD had a higher rate of successful voiding of the bladder after catheter removal compared with placebo (61.9% versus 47.9 percent, p=0.012). Alfuzosin 10 mg OD almost doubled the likelihood of a successful TWOC in these patients and its beneficial effect was particularly marked in patients with a high risk of TWOC failure, i.e. men over 65 years of age and/or with a retention volume of more than 1,000 ml.
 
In the second phase of the ALFAUR study, all patients who were successfully voided in the first phase were re-randomized to receive alfuzosin 10 mg OD or placebo for a further period of six months to evaluate whether alfuzosin was able to reduce the need for BPH-related surgery defined by the recurrence of AUR or symptomatic impairment. The results of this phase of the study showed that:

“The ALFAUR trial demonstrates that alfuzosin, through its action on risk factors and sympathetic overactivity, allows for rapid catheter removal in patients with AUR and also significantly reduces the recurrence of AUR and the need for BPH-related surgery

in comparison with placebo in the medium term. This is clinically meaningful for physicians and offers patients hope for better treatment,” said S. Alan McNeill, MD, Department of Urology, Western General Hospital in Edinburgh, leading investigator of the ALFAUR trial.

Acute urinary retention, the sudden inability to urinate, is most commonly a complication of chronic benign prostatic hyperplasia. Typically the patient complains of severe pain and an inability to satisfactorily empty the bladder. The patient should be catheterised to reduce pain and avoid the risk of causing, or exacerbating, renal failure. Prompt urethral catheterisation is essential.

In elderly men, the risk of having an episode of acute urinary retention is remarkably high. Over 1 in 10 men in their 70s will experience acute urinary retention within the next five years. The risk for men in their 80s is nearly 1 in 3. Men who have moderate to severe symptoms of AUR have three times the risk of men with mild symptoms.

“On the basis of the ALFAUR study results, men with acute urinary retention can now expect a diminished need of having BPH-related surgery in urgency conditions which increase the mortality and morbidity of the intervention. With the on-going ALTESS study, we will see whether this beneficial effect could prevent the occurrence of a first episode of AUR in BPH patients” said Steven A. Kaplan, MD, Given Foundation Professor of Urology and Vice-chairman, College of Physicians and Surgeons at Columbia University, New York.

The ALFAUR trial was made possible by a grant from Sanofi-Synthelabo Research.

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

Forward-Looking Statements

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Investors and security holders may obtain a free copy of the Form 20-F and any other documents filed by Sanofi-Synthélabo with the SEC at www.sec.gov as well as of the Reference Document filed with the French Autorité des Marchés Financiers at www.amf-france.org or directly from Sanofi-Synthélabo on our web site at: www.sanofi-synthelabo.com.

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