Orexo reports continued strong AbstralTM sales in Europe

Uppsala, May 18, 2010 – Orexo AB (STO: ORX) today confirms that its partner, ProStrakan Group plc (LSE: PSK) has announced that AbstralTM continues to show strong sales development in 2010. AbstralTM was launched across Europe during the course of 2009 and ProStrakan reported sales of £5.8 million in its first year on the market. In the first four months of 2010 AbstralTM has already recorded sales of £5.0 million. The successful establishment in each of the countries in which it has been launched is demonstrated by the following market shares (estimates based on the number of doses recorded in March 2010): France 27%; Germany 20%; Spain 10%; Sweden 69%; and UK 21%. There is also evidence of a significant increase in the size of the market for fentanyl-based products for breakthrough cancer pain across the major EU-countries in which ProStrakan operates (France, Germany, Spain and the UK). This market has grown by 45% (Q1 2010 v Q1 2009) and of that growth, AbstralTM commanded a 61% share. Although invoiced sales to distributors (affected by changes in stock) showed a slight decline in the first quarter 2010 compared to the previous quarter, in-market sales (sales to end-customer) of AbstralTM continued to show a strong underlying growth of above 40% in Q1 2010 compared to Q4 2009 (source: IMS, March 2010). Commenting on today’s announcement, Torbjörn Bjerke, Orexo’s President and CEO, said: “AbstralTM is currently helping thousands of patients in Europe and it is encouraging that the product is leading the market growth within the treatment of breakthrough cancer pain. In our home market Sweden we currently have a market share of around 69% and have enjoyed an increase of approx. 40% in tablet sales in Q1 2010 compared to Q4 2009.” For further information, contact: Torbjörn Bjerke, President and CEO Tel: +46 (0)708-66 19 90 E-mail: torbjorn.bjerke@orexo.com Claes Wenthzel, Executive Vice President and CFO Tel: +46 (0)708-62 01 22 E-mail: claes.wenthzel@orexo.com About AbstralTM AbstralTM, developed by Orexo AB is a new, rapidly disintegrating, sublingual formulation of fentanyl, a long-established opioid used for the management of episodes of breakthrough pain experienced by cancer patients who are already receiving opioid analgesics for their chronic pain. It is based on Orexo’s unique and patented sublingual tablet technology in which a rapidly disintegrating tablet is placed under the tongue and the active substance is absorbed by the mucous membrane. Currently AbstralTM is sold in Sweden, UK, Germany, Spain, Greece, Ireland, Slovenia, Norway and France. An NDA for AbstralTM has been filed in the US and Canada by the partner ProStrakan and in Japan the product is being prepared for registration by the partner Kyowa Hakko Kirin. About Orexo Orexo is a pharmaceutical company focusing on developing treatments for pain and inflammation. The company has four products on the market as well as a broad project portfolio in late stages of development. Sales and product development are mainly carried out through worldwide partnership agreements with larger pharmaceutical companies. Orexo has its head office located in Uppsala, Sweden. More information can be found at www.orexo.com. Note: This is information that Orexo AB (publ) is required to disclose pursuant to the Swedish Financial Instruments Trading Act and/or the Swedish Securities Markets Act. The information was provided for public release on May 18, 2010 at 8:15 CET.