New Data Presented at American Urological Association Shows Trospium to Have Local Effect in The Bladder

Business Wire, May 23, 2005

LEXINGTON, Mass. -- Indevus Pharmaceuticals, Inc. (NASDAQ: IDEV) today announced that new data were presented at the American Urological Association (AUA) annual meeting in San Antonio, on May 22, 2004, from a research study in an animal model of the over-active bladder condition that was recently completed by Michael Chancellor, M.D., at the University of Pittsburgh. The data show that trospium chloride not only assists in controlling symptoms of overactive bladder when taken orally, but also controls symptoms when local contact is made with the bladder wall. Trospium chloride is co-promoted by Indevus Pharmaceuticals, Inc. under the name SANCTURA(R).

"When taken orally, certain classes of drugs can control the muscle contractions that cause conditions like overactive bladder. In this study, we have found one drug, trospium chloride, reacts with the bladder muscle as urine is stored in the bladder," said Michael Chancellor, M.D., professor, department of urology, University of Pittsburgh School of Medicine. "It is exciting to see that this drug could be helping overactive bladder patients in more ways than we had previously thought."

Study design

Animals were given carbacol to induce bladder overactivity. The animals received urine, placed directly into the bladder, from human subjects taking one of the following: trospium, tolterodine LA, oxybutynin XL and urine from a control subject, in order to see whether any drug present in the urine following oral administration could reduce the effect of carbacol.

Study findings

Urine from subjects who had taken trospium (administered directly into the bladder of animals) blocked the effect of carbacol, demonstrating a local effect in the bladder. Conversely, carbacol-induced bladder overactivity was not blocked in animals whose bladders had received urine from humans who had received tolterodine or oxybutynin or from the untreated control demonstrating that there was no local effect seen from these agents.

These findings may be relevant given that 60% of the absorbed dose of trospium chloride is excreted in to the bladder unchanged as trospium.

Background

Trospium chloride belongs to a class of anticholinergic compounds known as muscarinic receptor antagonists. These compounds relax smooth muscle tissue found in the bladder, thus decreasing bladder contractions. Overactive or unstable detrusor muscle function is believed to be the cause of overactive bladder.

About Indevus

Indevus Pharmaceuticals is a biopharmaceutical company engaged in the acquisition, development and commercialization of products targeting certain medical specialty areas, including urology and infectious diseases. The Company currently markets SANCTURA(R) for overactive bladder and has multiple compounds in clinical development, including PRO 2000 for the prevention of infection by HIV and other sexually transmitted pathogens, pagoclone for stuttering, aminocandin for systemic fungal infections, and IP 751 for interstitial cystitis.

SANCTURA(R) is indicated for the treatment of overactive bladder with symptoms of urge urinary incontinence, urgency and urinary frequency. The most commonly reported side effects in Phase III U.S. clinical trials were dry mouth (20.1 percent for SANCTURA vs. 5.8 percent for placebo) and constipation (9.6 percent for SANCTURA vs. 4.6 percent for placebo). Patients who have urinary retention, gastric retention, uncontrolled narrow-angle glaucoma or hypersensitivity to SANCTURA should not use SANCTURA.

Except for the descriptions of historical facts contained herein, this press release contains forward-looking statements that involve risks and uncertainties that could cause the Company's actual results and financial condition to differ materially from those anticipated by the forward-looking statements. These risks and uncertainties are set forth in the Company's filings under the Securities Act of 1933 and the Securities Exchange Act of 1934 under "Risk Factors" and elsewhere, and include, but are not limited to: dependence on the success of SANCTURA(R) and SANCTURA XR(TM); the early stage of products under development; uncertainties relating to clinical trials, regulatory approval and commercialization of our products, particularly SANCTURA and SANCTURA XR; risks associated with contractual agreements, particularly for the manufacture and co-promotion of SANCTURA and SANCTURA XR; dependence on third parties for manufacturing and marketing; competition; need for additional funds and corporate partners, including for the development of our products; failure to acquire and develop additional product candidates; history of operating losses and expectation of future losses; product liability and insurance uncertainties; risks relating to the Redux-related litigation; limited patent and proprietary rights; dependence on market exclusivity; valuation of our Common Stock; risks related to repayment of debts; risks related to increased leverage; and other risks.