Last updated on April 21, 2014 at 7:52 EDT

Oncothyreon Initiates Phase 1/2 Trial of PX-866 in Combination with Vemurafenib

May 31, 2012

SEATTLE, May 31, 2012 /PRNewswire/ – Oncothyreon Inc. (Nasdaq: ONTY) today
announced the initiation of a Phase 1/2 trial of PX-866 in combination
with vemurafenib (Zelboraf®).  PX-866 is Oncothyreon’s investigational
small molecule compound designed to inhibit the activity of
phosphatidylinositol-3-kinase (PI-3K), a component of an important cell
survival signaling pathway.  Vemurafenib is a kinase inhibitor
indicated for the treatment of unresectable or metastatic melanoma with
the BRAF(V600E) mutation.

The Phase 1 portion of this trial will evaluate the safety and
tolerability of PX-866 in combination with twice daily oral
administration of vemurafenib in up to 36 patients with any BRAF-mutant
cancer.  The trial will use a dose-escalation design to evaluate up to
three dose levels of PX-866 with up to two dose levels of vemurafenib
to determine the maximally tolerated or recommended dose of both PX-866
and vemurafenib to be used in Phase 2.  The Phase 2 portion of the
trial will compare the anti-tumor activity and safety of PX-866 and
vemurafenib at the doses recommended from Phase 1 with vemurafenib
alone administered at the approved dose.  This randomized Phase 2 trial
is expected to enroll 110 patients with advanced BRAF-mutant melanoma
and has a primary endpoint of progression-free survival.

This Phase 1/2 trial is being conducted in collaboration with the
Melanoma Research Foundation Breakthrough Consortium (MRFBC).  Lynn M.
Schuchter, M.D., Chief of the Hematology Oncology Division and leader
of the melanoma program at the Abramson Cancer Center of the University
of Pennsylvania, a member of the MRFBC, said, “While vemurafenib has
significantly prolonged the lives of patients with BRAF-mutant
melanoma, many patients develop resistance.  Preclinical evidence
suggests that the PI-3 kinase pathway may contribute to this
resistance, and we are therefore excited to begin this study.”

“We are grateful to the MRFBC for proposing and performing this study,”
said Robert L. Kirkman, M.D., President and Chief Executive Officer of
Oncothyreon.  “With the initiation of this trial, Oncothyreon is now
conducting five Phase 2 trials of PX-866 in six different tumor types,
a broad development program reflecting our enthusiasm for this product

About the Melanoma Research Foundation Breakthrough Consortium

The mission of the Melanoma Research Foundation Breakthrough Consortium
(MRFBC) is to accelerate research and development of the most promising
therapeutics in melanoma to deliver curative treatment options to
patients.  The Consortium was created in 2010 and consists of basic
scientists, translational researchers and investigators from 13 centers
of excellence in melanoma, including all of the centers designated by
National Cancer Institute as a Specialized Program of Research
Excellence (SPORE) in skin cancer.  The MRFBC works through
collaborative private, public and nonprofit partnerships to facilitate,
conduct or enhance the development of the most promising combination
therapies – a strategy which has been shown to be the cornerstone of
success in treating diseases such as TB and HIV.  In addition to
support of high-impact clinical trials, key initiatives include
preclinical testing of compounds in combination, development of a
collaborative virtual specimen bank operating under common standards,
and development of a translational research agenda across trials. 
Clinical trials supported by the MRFBC are opening this year.

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 above trial, current trials include a 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) and
a Phase 1/2 trial of PX-866 in combination with the chemotherapeutic
agent docetaxel in patients with locally advanced, recurrent or
metastatic non-small cell lung cancer or SCCHN. In addition, the NCIC
Clinical Trials Group is conducting two Phase 2 trials, one in patients
with recurrent or metastatic castration- resistant prostate cancer and
one in patients with glioblastoma multiforme that has recurred during
or following primary therapy.

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.

SOURCE Oncothyreon Inc.

Source: PR Newswire