BELLEVUE, WA, June 11 /PRNewswire-FirstCall/ - Oncothyreon Inc. (Nasdaq:ONTY) (TSX: ONY) (the 'Company') today announced that the first patient hasbeen treated in a Phase 1b clinical trial of PX-12 in patients with advancedmetastatic cancer. PX-12 is a proprietary small molecule inhibitor ofthioredoxin, a protein that regulates diverse molecular pathways thatcontribute to the growth, survival and drug resistance of many cancers.

The primary objective of the Phase 1b dose-escalation trial is todetermine the safety and tolerability of a 72-hour continuous infusion ofPX-12 given on the first three days of a 21-day cycle. Other objectives of thetrial include an evaluation of the pharmacokinetics and pharmacodynamics ofthe prolonged infusion, together with identification of any anti-tumoractivity. The trial is expected to enroll up to 28 patients at three centersin the United States.

About PX-12

PX-12 is a small molecule designed to inhibit thioredoxin-1. Increasedlevels of thioredoxin-1 have been noted in many types of cancer cells,including hepatoma, lung cancers, squamous cervical carcinoma, primary gastriccancers and colorectal carcinomas. Increased levels of thioredoxin-1 areassociated with decreased sensitivity to a variety of common chemotherapyagents and may cause or contribute to drug resistance.

An initial Phase 1 trial of PX-12 in 38 patients with advanced metastaticcancer showed that PX-12 was well tolerated and produced a decrease in plasmaconcentrations of thioredoxin that was significantly correlated with increasedpatient survival. Fifteen of the 38 patients achieved stable disease of up to322 days. Oncothyreon is also currently conducting a Phase 2 trial of PX-12given as a 3-hour infusion daily for five days of a 21-day cycle in patientswith advanced pancreatic cancer who have progressed on gemcitabine or agemcitabine-containing regimen.

About Oncothyreon

Oncothyreon is a biotechnology company specializing in the development ofinnovative therapeutic products for the treatment of cancer. Oncothyreon'sgoal is to develop and commercialize novel synthetic vaccines and targetedsmall molecules that have the potential to improve the lives and outcomes ofcancer patients.