( onders.Patients defined as responders ...)Topline Results of Phase III Study in Acute Ischemic Stroke,(Dias-2) Do Not Demonstrate Difference Between Desmoteplase and,Placebo,Health

Improvement of clinical outcome was found with 47.4% of patients treated with 90 mcg/kg Desmoteplase and 36.4% of patients treated with 125 mcg/kg Desmoteplase, compared to 46.0% in the placebo group with neither dose of Desmoteplase statistically significantly different compared to placebo.

The rate of symptomatic intracranial bleeding within 72 hours after study drug administration was 0% in the placebo group, 3.5% in the 90 mcg/kg dose group and 4.5% in the 125 mcg/kg group. There were four patient deaths reported in the placebo group, three reported in the 90 mcg/kg dose group and 14 reported in the 125 mcg/kg dose group within the 90 day follow-up period. Ten of the 14 deaths in the 125 mcg/kg dose group were considered by the investigators as not related to the drug, 9 of which occurred 14 or more days after stroke and were from non-neurological causes.

These data are surprising and are not consistent with previously observed patterns in the DIAS/DEDAS trials and larger size, placebo-controlled acute stroke trials. The absence of consistency with previous findings is not easy to explain, but in-depth analyses are planned to better understand the data.

Forest will review the complete study database over the coming weeks to determine the appropriate next steps and its role regarding U.S. development of desmoteplase.

The headline results of the DIAS-2 study will be presented on 1 June 2007 at 10:45 a.m. BST within the "Large Clinical Trials II" session at the XVI European Stroke Conference in Glasgow, Scotland, U.K.

PAION will host a conference call on 1 June 2007 to discuss the DIAS-2 headline results starting at 1:00 p.m. BST (02:00 p.m. CEST, 08:00 a.m. EDT). To access the call please dial +44 20 7138 0819 UK, +49 69 9897 2634 Germany, +1 718 354 1361 USA. Title: "PAION DIAS-2 results"