Oncothyreon Advances to Phase 2 Portion of Phase 1/2 Trial of PX-866 in Combination with Docetaxel

SEATTLE, WA, Oct. 20, 2011 /PRNewswire/ - Oncothyreon Inc. (Nasdaq: ONTY) today announced it has initiated the Phase 2 portion of  its ongoing Phase 1/2 trial of PX-866 in combination with the chemotherapeutic agent docetaxel (Taxotere^®) following successful completion of the Phase 1 dose escalation portion of the study. PX-866 is a small molecule compound designed to inhibit the activity of phosphatidylinositol-3-kinase (PI-3K), a component of an important cell survival signaling pathway.

The primary objective of the Phase 1 portion of the trial was to determine the maximum tolerated or recommended daily dose of PX-866 to be given in combination with the standard dose of docetaxel administered once every three weeks to patients with advanced cancers for which docetaxel is considered standard of care. The Phase 1 portion enrolled a total of 43 patients treated at 3 different dose levels of PX-866 in combination with the standard dose of docetaxel. Preliminary results indicated that combination treatment was well tolerated and associated with an encouraging disease control rate. The recommended daily dose of PX-866 in combination with docetaxel was determined to be the same as the single agent daily maximum tolerated dose.  Additional results from the Phase 1 portion of the trial will be submitted for presentation at an upcoming scientific meeting.

The Phase 2 portion of the trial is an open-label, randomized evaluation of the antitumor activity and safety of PX-866 administered at the recommended daily dose in combination with docetaxel, versus docetaxel alone, in two groups of patients.  Group 1 will enroll patients with non-small lung cancer receiving second or third line treatment. Group 2 will enroll patients with locally advanced, recurrent or metastatic squamous cell carcinoma of the head and neck after failure of prior therapy. The two groups will be randomized and evaluated independently.

Up to 170 patients may be enrolled in the Phase 2 portion of the study including 88 (44 per arm) in Group 1 and 82 patients (41 per arm) in Group 2. The primary endpoint of the Phase 2 portion is progression free survival. Secondary endpoints include objective response rate and overall survival.  Additional information on the trial is available at clinicaltrials.gov.

About PX-866

PX-866 is a pan inhibitor of the PI-3K/PTEN/AKT pathway, a critical cell signaling pathway that is activated in many types of human cancer. Aberrant activation and regulation of PI-3K is implicated in a large proportion of human cancers, where it leads to increased proliferation and inhibition of apoptosis (programmed cell death).

Oncothyreon is conducting a broad development program of PX-866 as a single agent and in combination with other agents in multiple cancer types. In addition to the randomized Phase 1/2 trial of PX-866 in combination with docetaxel described above, other current trials include a randomized Phase 1/2 trial of PX-866 in combination with cetuximab (Erbitux®) in patients with metastatic colorectal carcinoma or progressive, recurrent or metastatic squamous cell carcinoma of the head and neck (SCCHN). In addition, the NCIC Clinical Trials Group is conducting two Phase 2 trials, glioblastoma multiforme that has recurred during or following primary therapy and one in patients with recurrent or metastatic castration-resistant prostate cancer.

About Oncothyreon

Oncothyreon is a biotechnology company specializing in the development of innovative therapeutic products for the treatment of cancer. Oncothyreon's goal is to develop and commercialize novel synthetic vaccines and targeted small molecules that have the potential to improve the lives and outcomes of cancer patients. For more information, visit www.oncothyreon.com.

Forward Looking Statements

In order to provide Oncothyreon's investors with an understanding of its current intentions and future prospects, this release contains statements that are forward looking, including statements related to future clinical development plans for our product candidates. These forward-looking statements represent Oncothyreon's intentions, plans, expectations and beliefs and are based on its management's experience and assessment of historical and future trends and the application of key assumptions relating to future events and circumstances.

Forward-looking statements involve risks and uncertainties, including risks and uncertainties related to Oncothyreon's business and the general economic environment. Many of these risks and uncertainties are beyond Oncothyreon's control. These risks, uncertainties and other factors could cause our actual results to differ materially from those projected in forward-looking statements. Risks, uncertainties, and assumptions include those predicting the timing, duration and results of clinical trials, the timing and results of regulatory reviews, the safety and efficacy of our product candidates, and the indications for which our product candidates might be developed. There can be no guarantee that the results of preclinical studies or clinical trials will be predictive of either safety or efficacy in future clinical trials. These and other risks and uncertainties are described in the reports and other documents filed by Oncothyreon Inc. with the SEC and/or Canadian regulatory authorities.

Although Oncothyreon believes that any forward-looking statements contained herein are reasonable, it can give no assurance that its expectations are correct. All forward-looking statements are expressly qualified in their entirety by this cautionary statement. For a detailed description of the risks and uncertainties associated with Oncothyreon, you are encouraged to review the official corporate documents filed with the securities regulators in the United States on U.S. EDGAR and in Canada on SEDAR. Oncothyreon is under no obligation to (and expressly disclaims any such obligation to) update or alter its forward-looking statements whether as a result of new information, future events, or otherwise.

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SOURCE Oncothyreon Inc.