SEATTLE, WA, Oct. 7, 2013 /PRNewswire/ - Oncothyreon Inc. (NASDAQ: ONTY) today
announced the presentation of final results from the first Phase 1
trial of ONT-380 at the American Association for Cancer Research
Special Conference on Advances in Breast Cancer Research in San Diego.
The results were presented by Virginia F. Borges, M.D., Associate
Professor in the Division of Medical Oncology, University of Colorado
School of Medicine. ONT-380 (also known as ARRY-380) is an orally
active, reversible and selective small-molecule HER2 inhibitor being
developed by Oncothyreon in collaboration with Array BioPharma Inc.
(Nasdaq: ARRY), Boulder, Colorado.
The first-in-human Phase 1 trial, with both dose-escalation and
expansion components, enrolled a total of 50 patients, 43 of whom had
HER2+ metastatic breast cancer. In this study, ONT-380 demonstrated an
acceptable safety profile; treatment-related adverse events were
primarily Grade 1. Because ONT-380 is selective for HER2 and does not
inhibit EGFR, there was a low incidence and severity of
treatment-related diarrhea, rash and fatigue, side effects which have
been associated with EGFR inhibition. A single patient experienced
Grade 2 treatment-related diarrhea and no patient developed
treatment-related Grade 3 diarrhea; one patient had a Grade 3 rash.
Additionally, there were no treatment-related cardiac events or Grade 4
treatment-related adverse events reported. The maximum tolerated dose
of ONT-380 established in this Phase 1 trial was 600 mg twice daily.
The dose-limiting toxicity was reversible elevation in liver enzymes.
In this trial, 22 HER2+ breast cancer patients with measurable disease
were treated with ONT-380 at doses greater than or equal to 600 mg BID.
In this heavily pretreated patient population, there was a clinical
benefit rate (partial response [n = 3] plus stable disease for at least
6 months [n = 3]) of 27%. Notably, two of the patients with partial
responses during treatment with ONT-380 had confirmed progressions
while on prior lapatinib- and trastuzumab-containing regimens.
"We believe that ONT-380's selectivity for HER2, without also targeting
EGFR, positions ONT-380 as a potential best-in-class small molecule
HER2 inhibitor," said Robert L. Kirkman, M.D., President and Chief
Executive Officer of Oncothyreon. "Results from this first-in-human
trial provide preliminary evidence of activity against HER2+ breast
cancer with a low incidence of EGFR-related side effects. We are
looking forward to the initiation of Oncothyreon's planned Phase 1b
trials of ONT-380, which we currently expect to begin before year end."
ONT-380 is an orally active, reversible and selective HER2 inhibitor. In
multiple preclinical tumor models, ONT-380 was well tolerated and
demonstrated significant dose-related tumor growth inhibition that was
superior to Herceptin® (trastuzumab) and Tykerb® (lapatinib).
Additionally, in these models, ONT-380 demonstrated synergistic or
additive tumor growth inhibition when dosed in combination with the
standard-of-care therapeutics Herceptin or Taxotere® (docetaxel).
ONT-380 has also demonstrated superior activity, based on overall
survival, compared to lapatinib and to the investigational drug,
neratinib, in an intracranial HER2+ breast cancer xenograft model.
Under the collaboration agreement with Array, Oncothyreon will conduct
the clinical development of ONT-380 through a defined set of
combination proof-of-concept trials in patients with metastatic breast
cancer, including patients with brain metastases. Oncothyreon
currently expects to initiate its clinical development of ONT-380 in
the fourth quarter of 2013. In addition, an investigator-sponsored
trial of ONT-380 in combination with trastuzumab in patients with brain
metastases from HER2+ breast cancer is underway. The trial is being
conducted under the sponsorship of the Dana-Farber Cancer Institute,
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.
In order to provide Oncothyreon's investors with an understanding of its
current results and future prospects, this release contains statements
that are forward-looking. Any statements contained in this press
release that are not statements of historical fact may be deemed to be
forward-looking statements. Words such as "believes," "anticipates,"
"plans," "expects," "will," "intends," "potential," "possible" and
similar expressions are intended to identify forward-looking
statements. These forward-looking statements include Oncothyreon's
expectations regarding clinical development activities.
Forward-looking statements involve risks and uncertainties related to
Oncothyreon's business and the general economic environment, many of
which are beyond its control. These risks, uncertainties and other
factors could cause Oncothyreon's actual results to differ materially
from those projected in forward-looking statements, including 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. Although
Oncothyreon believes that the 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 Oncothyreon's risks and uncertainties, you are encouraged to review
the documents filed with the securities regulators in the United States
on EDGAR and in Canada on SEDAR. Oncothyreon does not undertake any
obligation to publicly update its forward-looking statements based on
events or circumstances after the date hereof.
Additional information relating to Oncothyreon can be found on EDGAR at www.sec.gov and on SEDAR at www.sedar.com.
SOURCE Oncothyreon Inc.