SangStat Medical Corp. and Pasteur Merieux Connaught Announce Filing of Marketing Clearance Application for THYMOGLOBULIN with FDA; SangStat has Exclusive Rights for USA and Canada; Thymoglobulin is Europe's Leading Antibody Treatment for Transplantation.

MENLO PARK, Calif. and LYON, France--(BUSINESS WIRE)--Jan. 6, 1997-- SangStat, The Transplant Company (Nasdaq: SANG) and the IMTIX Division of Pasteur Merieux Connaught (Rhone-Poulenc group) announced today the filing of SangStat's product licence application (PLA) for market clearance of THYMOGLOBULIN with the U.S. Food and Drug Administration (FDA). The application includes the positive results of SangStat's U.S. pivotal Phase III trial showing that successful reversal of acute graft rejection was more frequent, significantly, in the THYMOGLOBULIN than in the control treated adult kidney transplant patients (87.8% Vs. 76.3%). These data, however, have not yet been reviewed by the FDA.

Philippe Pouletty, M.D., SangStat's Chairman and CEO said, "We are very excited to be filing the PLA for THYMOGLOBULIN so soon after we filed the AADA for SangStat's CYCLOSPORINE last November. Subject to approval, these two therapeutic products can help us address the U.S. transplant community's need to effectively prevent and treat graft rejection, a significant cause of graft loss."

THYMOGLOBULIN has been approved in 39 countries, used in more than 30,000 patients worldwide and is a market leader in Europe for the treatment and prevention of acute graft rejection episodes in transplant recipients. SangStat acquired the exclusive rights to develop and market THYMOGLOBULIN in the U.S. and Canada from Pasteur Merieux Connaught in 1993.

"We are very pleased with SangStat's achievements with the success of the Phase III trial and the rapid final preparation of the PLA submission," said Gilles Alberici, Ph.D., Head of IMTIX, the Pasteur Merieux Connaught Transplant Division.

In the U.S. SangStat is seeking marketing approval for use of THYMOGLOBULIN to treat acute graft rejection episodes in kidney transplant recipients. The regulatory approval process for a biological product involves the submission of an Establishment License Application (ELA) for the manufacturing process and facility, while the product characteristics, non-clinical and clinical data, are submitted in a Product License Application (PLA). SangStat expects to be the product license holder for the U.S.

"The results of the U.S. pivotal phase III trial with THYMOGLOBULIN have been critical to finalizing the PLA," said Tim Schroeder, SangStat's Executive V.P. of Clinical Development. "These positive results further expand the extensive clinical safety and efficacy data gathered by IMTIX from European experience and seen more recently in our compassionate IND patients treated with THYMOGLOBULIN in the U.S. and Canada." In the United States, SangStat has provided THYMOGLOBULIN for compassionate use to 46 patients.

A supplement to an approved ELA to provide for the manufacturing process and facility for THYMOGLOBULIN was submitted and accepted for filing by the FDA in August, 1996. Once the agent is approved, Pasteur Merieux Connaught will be the manufacturer of commercial supplies of THYMOGLOBULIN for distribution in the United States. THYMOGLOBULIN is manufactured and marketed outside North America by IMTIX, the Pasteur Merieux Connaught transplantation division.

THYMOGLOBULIN is a pasteurized, rabbit anti-human thymocyte polyclonal antibody preparation which induces immunosuppression as a result of T-cell depletion. Common side effects of anti-human thymocyte polyclonal antibody therapy include, among others, fever, infections, leukopenia and thrombocytopenia. These side effects are often transient. THYMOGLOBULIN is contraindicated in patients with an allergy to rabbit proteins.

Preliminary results of the Phase III trial, including the subgroup analysis, were presented at a symposium on Antibody Therapy in the 90's held at the Annual Scientific Meeting of the National Kidney Foundation in New Orleans in November, 1996. More detailed analysis of the results are expected to be presented at the American Society of Transplant Physicians Annual Meeting in Chicago in May, 1997.

SangStat is a biopharmaceutical company applying a disease management approach to improve the outcome of organ transplantation. The Company has a broad portfolio of monitoring and therapeutic products, product candidates and technologies to address the pre-transplant, acute care and chronic phases of transplantation. SangStat is located in Menlo Park, California, and operates The Transplant Pharmacy, a comprehensive pharmacotherapy management program, and wholly-owned subsidiaries, SangStat Atlantique S.A., SangStat's European base of operations in Nantes, France, SangStat Canada, Ltd. in Mississauga, Ontario, Canada, and XenoStat, Inc., in Menlo Park, California.

IMTIX was established in 1995 as a specific division of Pasteur Merieux Connaught dedicated to biologicals for transplantation and hematology. Its products are distributed in more than 60 countries including most of the EU countries, Canada, Brazil, South Africa and Japan. IMTIX also has an active development program of therapeutics for acute care. IMTIX takes part fully in the mission of Pasteur Merieux Connaught: to contribute as a global leader to the protection and maintenance of human health by creating superior immunological products. Pasteur Merieux Connaught is part of the Rhone-Poulenc group and refers to Pasteur Merieux Serums & Vaccins of Lyon, France and its subsidiaries, including Connaught Laboratories, Ltd., in Toronto, Canada and Connaught Laboratories, Inc. in Swiftwater, Pennsylvania.

This press release contains forward-looking statements that involve risks and uncertainties. Forward-looking statements reflect the Company's current views with respect to future events. Actual results may vary materially and adversely from those anticipated, believed, estimated, or otherwise indicated. Important factors common to the FDA drug review and approval process could cause actual results to differ materially with regard to the approvability of SangStat's CYCLOSPORINE or THYMOGLOBULIN. These factors include, without limitation, (1) that data obtained from clinical trials are subject to varying interpretations, and there can be no assurance that the FDA (or an FDA panel of experts) will agree with the Company's assessment of clinical trial results; (2) that there can be no assurance that the agency will not issue new guidelines, guidance documents, policies, or regulations or otherwise have new, different or previously unknown requirements that may materially affect the approvability of the CYCLOSPORINE AADA, THYMOGLOBULIN ELA or PLA; and (3) that there can be no assurance of FDA acceptance for filing or of FDA approval of the AADA, ELA or PLA. Other factors that could cause actual results to differ materially include, without limitation, uncertainty related to the manufacturing of commercial quantities of CYCLOSPORINE or THYMOGLOBULIN on commercially favorable terms, market acceptance and potential litigation. For a discussion of factors that might result in different outcomes, see the section under the caption "Risk Factors" beginning on page 30 of the 1995 Annual Report to Stockholders.

CONTACT: SangStat Medical Corporation

Maree Wall, 415/328-0300

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IMTIX - France

Pasteur Merieux Connaught

Ariane Mansouri, 33.4.72.73.79.76

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