Apheresis with Cypress Bioscience's PROSORBA Column Offers New Therapeutic Option For Rheumatoid Arthritis Patients Study Published in Arthritis and Rheumatism.

SAN DIEGO--(BW HealthWire)--Oct. 11, 1999--

An article in the October 1999 issue of Arthritis and Rheumatism reports that therapeutic apheresis using the PROSORBA(R) column blood-filtration device from Cypress Bioscience, Inc. (Nasdaq:CYPB) is an efficacious treatment option for rheumatoid arthritis patients with active disease who have failed other treatments.

In March 1999, the U.S. Food and Drug Administration approved the PROSORBA column for use in the therapeutic reduction of the signs and symptoms of moderate to severe rheumatoid arthritis in adult patients with long standing disease who have failed or are intolerant to disease-modifying anti-rheumatic drugs (DMARDs).

The article entitled "The PROSORBA Column for Treatment of Refractory Rheumatoid Arthritis," reported on the randomized, double-blind, sham-controlled pivotal Phase III clinical trial. Originally planned for 268 patients, the Phase III trial was stopped after enrollment of 109 patients by the independent data safety monitoring board (DSMB) due to favorable safety and statistically significant efficacy results.

"Patients with rheumatoid arthritis who failed other conventional treatments have, until recently, had few therapeutic options," said David T. Felson, M.D., M.P.H., Professor of Medicine and Public Health, Boston University Arthritis Center and the lead author of the article, "The PROSORBA column may be particularly useful in treating these patients."

This trial included the most severe rheumatoid arthritis patients studied to date. Patients in the trial had rheumatoid arthritis for an average of 15.5 years and had failed an average of 4.2 different disease modifying anti-rheumatic drugs (DMARD)ts with PROSORBA or sham apheresis, with efficacy evaluated seven to eight weeks after treatment ended. Patients were characterized as responders if they experienced improvement according to the American College of Rheumatology (ACR) definition of improvement at the efficacy time point.

On an intent-to-treat basis where patients were analyzed whether or not they completed the full course of treatment, 47 patients in the PROSORBA arm or 31.9% experienced ACR-defined improvement versus 11.4% of the 44 patients in the sham-treated arm (p value = 0.019 after adjustment for interim analysis). When the results of eight additional patients were added to this analysis, the findings were unchanged. The remaining ten patients who received treatment at the time the trial was halted continued treatment on an unblinded basis and was excluded from the efficacy evaluation.

A subsequent analysis by the company not reported in the article showed that of the 34 PROSORBA column-treated patients who completed the prescribed course of 12 treatments, 44.1% had significant clinical improvement by ACR criteria compared to 16.1% of the 31 patients in the sham-treated arm (p value = 0.015).

The treatment using the PROSORBA column involved a two-hour procedure, similar to dialysis, once a week for twelve weeks. The PROSORBA column is used in conjunction with an apheresis machine, which separates the blood cells from the plasma, the liquid portion of the blood. The plasma then passes through the PROSORBA column, which removes antibodies from the immune system. Thereafter, the plasma is returned, along with the cells, to the patient.

Rheumatoid arthritis affects approximately 2.5 million people in the U.S. alone. Although there are a number of drugs currently available to treat this disease, each has drawbacks and none is effective in all patients. In current medical practice for treating Rheumatoid Arthritis, patients are usually treated first with nonsteroidal anti-inflammatory drugs (NSAID's) which primarily relieve the symptoms, but do not alter the course of the disease. If patients show disease progression, they are then treated with DMARD's, that may have severe side effects. The PROSORBA column offers a unique non-drug alternative for patients who have failed DMARD's, or who are unable to tolerate such drugs.

Arthritis & Rheumatism is the official journal of the American College of Rheumatology and the world's leading rheumatology journal. In addition to Dr. Felson, the article was authored by the PROSORBA column clinical investigators.

About Cypress Bioscience, Inc.

Cypress Bioscience, Inc. develops and markets medical devices and therapeutics for the treatment of certain types of immune disorders and is engaged in the development of novel therapeutic agents for the treatment of blood platelet disorders. In March 1999, the company entered into an agreement that granted Fresenius AG anA in 1987 for use in Idiopathic Thrombocytopenic Purpura (ITP), an immune bleeding disorder. In addition, Cypress is developing Cyplex(TM) (Infusible Platelet Membranes), which is positioned to become an alternative for traditional platelet infusions. For more information about the PROSORBA column and Cypress, please visit the company's Web site at www.cypressbio.com.

Except for historical information contained herein, this news release contains forward-looking statements regarding Cypress Bioscience, Inc. that involve risks and uncertainties, including, but not limited to the Company's and Fresenius' ability to market successfully the PROSORBA column for use as a treatment for rheumatoid arthritis; whether the Company will be successful in collaborating with Fresenius; and the Company's ability to develop and receive regulatory approval for Cyplex(TM) on a timely basis, if at all, as well as other risks detailed from time to time in the Company's SEC reports, including its Annual Report on Form 10-K for the year ended Dec. 31, 1998 and its most recent Quarterly Report on Form 10-Q.