Nexell Therapeutics Obtains Exclusive License to Antibody Portfolio in New Agreement With Diaclone; Nexell Also Receives Right of First Refusal for In Vivo Applications.

Health/Medical Writers

BIOWIRE2K

IRVINE, Calif.--(BW HealthWire)--June 8, 2000

Nexell Therapeutics Inc. (Nasdaq: NEXL), one of the world's leading suppliers of therapeutic and diagnostic products based on stem cell technology, announced today that it has converted its worldwide licensing agreement with Diaclone, SA, to an exclusive license for six monoclonal antibodies for use in ex vivo cell therapy. In January, the companies announced an agreement granting Nexell Therapeutics non-exclusive rights to this portfolio.

The agreement also gives Nexell Therapeutics right of first refusal for potential in vivo applications of these antibodies, such as treatment of graft versus host disease (GVHD) with CD25.

"One of the keys to immunomagnetic cell selection or purging is the antibody. Quite simply, the more antibodies we have access to, the larger the number of different cell types we can select with our instrumentation," said L. William McIntosh, President and COO of Nexell Therapeutics. "Moving to an exclusive license for these antibodies gives us a significant competitive advantage in developing new applications for our selection platform. And for the first time, we've also obtained the right to acquire and pursue promising applications that involve direct therapeutic uses of these proteins in patients."

The agreement grants Nexell Therapeutics exclusive access to both finished product and the master cell lines necessary to produce the six monoclonal antibodies. This portfolio includes CD138, useful for purging myeloma cells; CD25, a T cell activation marker that may facilitate the removal of alloreactive cells (thought to be responsible for GVHD) from a stem cell graft prior to transplant; CD56 and CD16, markers for NK (natural killer) cells; CD14, a monocyte marker; and CD4, the marker for T-helper cells.

Diaclone, SA

Located in Besancon, France, Diaclone SA, directed by Dr. John Wijdenes, is a biotechnology company well known for the development of monoclonal antibodies for therapeutic, diagnostic and research purposes. Founded in 1986 as a laboratory for the Besancon Blood Bank, Diaclone is now a fully-owned subsidiary of the Biotest Group.

Nexell Therapeutics Inc.

Located in Irvine, California, Nexell Therapeutics Inc. (Nasdaq:NEXL) is a cell therapy company whose mission is to put the healing power of the cell into the hands of physicians. Nexell is developing and marketing innovative ex vivo cell therapies and in vitro diagnostics for cancer, autoimmune, metabolic and genetic diseases. Nexell's lead product, the Isolex(R) 300i Magnetic Cell Selection System, is the only FDA approved device commercially available for the selection of hematopoietic stem cells and the removal of tumor cells from autologous peripheral blood as a component of aggressive cancer treatment. In addition, Nexell markets the Cytonex(TM) ICC Staining Kit and an extensive line of cell therapy preparation, storage and expansion products including the Cryocyte(TM), SteriCell(R) and Lifecell(R) brands.

The Private Securities Litigation Reform Act of 1995 provides a "safe harbor" for certain forward-looking statements. The forward-looking statements contained in this release are subject to certain risks and uncertainties. Actual results could differ materially from current expectations. Among the factors which could affect the Company's actual results and could cause results to differ from those contained in the forward-looking statements contained herein are: the timely commencement and success of the Company's clinical trials and other research endeavors, delays in receiving FDA or other regulatory approvals, the development of competing therapies and/or technologies, the terms of any future strategic alliances, the possible need for additional capital, and any additional factors described from time to time in the Company's filings with the SEC.

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