GTC BIOTHERAPEUTICS ENTERS AGREEMENT FOR FURTHER CLINICAL PRODUCTION OF MM-093 FOR MERRIMACK PHARMACEUTICALS

GTC Biotherapeutics, Inc. ("GTC", Nasdaq: GTCB) announced today that it has entered into an agreement for further production of MM-093 for Merrimack Pharmaceuticals, Inc. MM-093, Merrimack's lead clinical product, is a recombinant version of human alpha-fetoprotein. Merrimack is conducting a Phase II study of MM-093 in patients with rheumatoid arthritis and is planning additional clinical studies. "We are pleased to continue to support Merrimack's supply needs for their clinical studies of MM-093," stated Gregory Liposky, GTC's Senior Vice President of Operations.

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