Active Biotech (NASDAQ OMX Nordic: ACTI) has today published data regarding a molecular target for the quinoline (Q) compounds in the scientific journal PLoS Biology, Volume 7, Issue 4, April 2009 (which is an open access journal and the full article is available at http://biology.plosjournals.org). Three of Active Biotech's projects (laquinimod, 57-57 and TASQ) belong to this chemical class of compounds. The details about the molecules and mechanisms underlying the development of autoimmune diseases, such as multiple sclerosis and systemic lupus erythematosus, are largely unknown. In this study it is shown that Q compounds bind to a molecule called S100A9 which is expressed in some white blood cells involved in the regulation of immune responses. Furthermore, it is shown that S100A9 interacts with two known pro-inflammatory receptors (Toll like receptor 4 (TLR4) and receptor of advanced glycation end products (RAGE)) and that this interaction is inhibited by Q compounds. The published data describe a new mechanism where S100A9 can promote pro-inflammation at early stages of immune activation. These findings may lead to an increased understanding of the early steps in the development of autoimmune disease. Lund, April 28, 2009 Active Biotech AB (Publ) Tomas Leanderson President & CEO Link to the journal: http://biology.plosjournals.org About Active Biotech Active Biotech AB (NASDAQ OMX NORDIC: ACTI), headquartered in Sweden, is a biotechnology company with R&D focus on autoimmune/inflammatory diseases and cancer. Projects in pivotal phase are laquinimod, an orally administered small molecule with unique immunomodulatory properties for the treatment of multiple sclerosis, as well as ANYARA for use in cancer targeted therapy, primarily renal cancer. Further key projects in clinical development comprise the three orally administered compounds TASQ for prostate cancer, 57-57 for SLE and RhuDex(TM) for RA. Please visit www.activebiotech.com for more information. Active Biotech is required under the Securities Markets Act to make the information in this press release public. The information was submitted for publication at 08:30 am CET on April 28, 2009. Active Biotech AB (org. no. 556223-9227) P.O. Box 724, SE-220 07 Lund, Sweden Tel +46 46-19 20 00 Fax +46 46-19 11 00