ProMetic's New MAbsorbent(R) Ligands Achieve Key Milestones

- Validation performed in collaboration with leading antibody manufacturers - New purification products targeted at $16 B monoclonal antibody (MAbs) market - Increased performance for manufacture of MAbs and antibody fragments MONTREAL, QUEBEC AND CAMBRIDGE, ENGLAND--(Marketwire - August 27, 2007) - ProMetic Life Sciences Inc. (TSX: PLI) ("ProMetic") announces that its UK-based subsidiary, ProMetic BioSciences Ltd ("PBL"), has achieved key performance milestones for its new MAbsorbent® ligands targeted at the purification of monoclonal antibodies ("MAbs") and recombinant antibody fragments ("Fabs"). The performance of ProMetic's new ligands against set targets was validated in collaboration with seven leading antibody producer companies in the United States and Europe. According to Dr. Steve Burton, PBL's Chief Executive Officer, "These new ligands are of strategic importance as, for the first time, they enable ProMetic to penetrate the monoclonal antibody purification market and derive revenues from the strong and consistent growth in demand for antibody therapeutics. With ligand development complete, we are now progressing to manufacturing scale-up and preparations for market launch by the end of this year." The market for monoclonal antibodies (MAbs and Fabs), currently estimated at $16 B, continues to demonstrate strong growth (CAGR greater than 20%). There are widespread concerns within the biomanufacturing community that manufacturing outputs and improvements in process yields and efficiencies are unable to keep pace with the ever increasing demand for MAbs required for therapeutic applications. An increasing number of monoclonal antibody products are antibody fragments as opposed to full chain antibodies. Theoretically Fabs are simpler to produce but can be difficult to purify as they lack the Fc region and cannot be purified with protein A, the standard approach for MAbs purification. Consequently Prometic's new ligand for Fabs purification addresses an un-met market need with significant growth potential. More on ProMetic MAbsorbent® ligands ProMetic's MAbsorbent® ligands, derived from PBL's synthetic Mimetic Ligand(TM) technology, are small synthetic molecules which have been engineered to specifically capture and purify antibodies. A feature of MAbsorbent® ligands is their increased robustness and lower cost compared to biological ligands such as Protein A. The existing MAbsorbent® products (A1P and A2P) are used primarily for the capture and purification of polyclonal antibodies from plasma (e.g. IVIG, hyperimmunes). Two new MAbsorbent® ligands have now been developed which are targeted at direct capture and purification of MAbs and Fabs. The first of these new ligands (A3P) binds to the antibody Fc region, provides high antibody recoveries and purities, and is capable of dynamic capacities in excess of 30g/litre. The second new ligand binds to a different region of the antibody molecule (light chain) and is targeted at the capture and purification of Fabs. More on the manufacturing challenges of MAb's Various industry reports point to growing concerns within the biomanufacturing community that manufacturing outputs and improvements in process yields and efficiencies are unable to keep pace with the ever increasing demand for MAbs required for therapeutic applications. In-part, these concerns stem from the inherent difficulties in capturing and purifying recombinant antibodies from bioreactors. Currently, the commonest approach to the purification of MAbs is to use affinity resins based upon immobilized protein A - a recombinant protein which binds selectively to a specific part (Fc region) of the antibody molecule. However, Protein A based resins are expensive to produce, have limited operational lifetimes and continued reliance on such materials is a concern to many MAb producers. ProMetic's new ligands offer a less-expensive and more robust alternative. About ProMetic Life Sciences Inc. ProMetic Life Sciences Inc. ( is a biopharmaceutical company specialized in the research, development, manufacture and marketing of a variety of commercial applications derived from its proprietary Mimetic Ligand(TM) technology. This technology is used in large-scale purification of biologics and the elimination of pathogens. ProMetic is also active in therapeutic drug development with the mission to bring to market effective, innovative, lower cost, less toxic products for the treatment of hematology and cancer. Its drug discovery platform is focused on replacing complex, expensive proteins with synthetic "drug-like" protein mimetics. Headquartered in Montreal (Canada), ProMetic has R&D facilities in the U.K., the U.S. and Canada, manufacturing facilities in the U.K. and business development activities in the U.S., Europe, Asia and in the Middle-East. About ProMetic BioSciences Ltd Using its unique and proprietary Mimetic Ligand(TM) technology, ProMetic BioSciences Ltd ("PBL") specializes in the development and manufacture of robust affinity separation materials which provide very high levels of purification. This is achieved by use of small chemical affinity ligands designed to bind a target biomolecule specifically and reversibly. In view of their use for the production of therapeutics, ProMetic's affinity products are manufactured to strict quality standards at PBL's GMP-compliant manufacturing facility on the Isle of Man, which completed a pounds sterling 1.5 million expansion in 2005. PBL also operates an R&D laboratory located on the Cambridge Science Park, United Kingdom. Forward Looking Statements This press release contains forward-looking statements about ProMetic's objectives, strategies and businesses that involve risks and uncertainties. These statements are "forward-looking" because they are based on our current expectations about the markets we operate in and on various estimates and assumptions. Actual events or results may differ materially from those anticipated in these forward-looking statements if known or unknown risks affect our business, or if our estimates or assumptions turn out to be inaccurate. Such risks and assumptions include, but are not limited to, the Company's ability to develop, manufacture, and successfully commercialize value-added pharmaceutical products, the availability of funds and resources to pursue R&D projects, the successful and timely completion of clinical studies, the ability of the Company to take advantage of business opportunities in the pharmaceutical industry, uncertainties related to the regulatory process and general changes in economic conditions. You will find a more detailed assessment of the risks that could cause actual events or results to materially differ from our current expectations on page 21 of the Company's Annual Information Form for the year ended December 31, 2006, under the heading "Risk Factors". As a result, we cannot guarantee that any forward-looking statement will materialize. We assume no obligation to update any forward-looking statement even if new information becomes available, as a result of future events or for any other reason. Contacts: ProMetic Biosciences Ltd Steve Burton Chief Executive Officer +44 1223 420 300 ProMetic Life Sciences Inc. Pierre Laurin President and CEO +1-514-341-2115 ProMetic Life Sciences Inc. Anne Leduc Manager, Communications +1-514-341-2115 ext.2234