MEMPHIS, Tenn--(BUSINESS WIRE)--
GTx, Inc. (NASDAQ: GTXI) today announced topline results of a
Phase II clinical trial evaluating Ostarine(TM) (MK-2866), an
investigational selective androgen receptor modulator (SARM), in
patients with cancer induced muscle loss, also known as cancer
cachexia. In this analysis, the study met its primary endpoint of
absolute change in total lean body mass (muscle) compared to placebo
and the secondary endpoint of muscle function (performance) after 16
weeks of treatment. GTx and Merck & Co., Inc. are collaborating to
develop Ostarine and other SARMs, which are a new class of drugs with
the potential to treat sarcopenia, which is the loss of skeletal
muscle mass resulting in reduced physical strength and ability to
perform activities of daily living, cancer cachexia, and other
musculoskeletal conditions.
GTx plans to present complete study results at an upcoming
scientific meeting in 2009.
"Cachexia continues to represent one of the most devastating
features of cancer," said an investigator in the Phase II clinical
trial, Adrian Dobs, MD, MHS, Professor of Medicine and Oncology and
Vice Chair of the Department of Medicine, Division of Endocrinology
and Metabolism, The Johns Hopkins University School of Medicine. "This
study provided encouraging evidence for using Ostarine to treat
patients with cancer cachexia by increasing lean body mass and
improving functional performance."
The clinical trial enrolled 159 cancer patients (average age of 66
years) with non-small cell lung cancer, colorectal cancer, non-Hodgkin
lymphoma, chronic lymphocytic leukemia, or breast cancer at 35 sites
in the US and Argentina. Participants were randomized to receive
placebo, 1 mg or 3 mg oral capsule of Ostarine once daily for 16
weeks. Average reported weight loss prior to entry among all subjects
was 8.8 percent. Subjects were allowed to have standard chemotherapy
during the trial. The drop out rate during the trial was 33 percent,
lower than the expected 50 percent rate which has been observed in
other cancer supportive care clinical trials.
The primary endpoint of the study was lean body mass measured by
dual energy X-ray absorptiometry (DEXA) scan. A prespecified analysis
was comparison of treatment arms with placebo using the exact Wilcoxon
rank sum test stratified by cancer type in patients with DEXA scans
performed at baseline and at the end of the study. Topline results
show that Ostarine treatment resulted in a statistically significant
increase in lean body mass compared to placebo. Ostarine treatment
resulted in clinically meaningful increases (greater than 1 kg) in
lean body mass compared to baseline in both the Ostarine 1 mg and 3 mg
treatment arms.
Topline results also show that Ostarine treatment improved muscle
function (performance) in a 12 step stair climb test measuring speed
and calculating power, a secondary endpoint of the study. No
improvement in speed or power was observed for the placebo group.
There were no improvements in the endpoints of grip strength and gait
speed.
The incidence of serious adverse events, deaths and tumor
progression were similar among placebo and the treatment arms. The
most common side effects reported among all subjects in the trial were
fatigue, anemia, nausea, and diarrhea. Changes in alanine amino
transferase (ALT), a marker of liver function, greater than twice the
upper limit of normal were observed in two patients in the placebo,
Ostarine 1 mg and Ostarine 3 mg cohorts. No subjects discontinued
treatment as a result of ALT changes.
"We are excited that Ostarine met the primary endpoint of the
Phase II cancer cachexia clinical trial," said Mitchell S. Steiner,
MD, CEO of GTx. "Even with the background of a heterogeneous cancer
population, cancer induced inflammation, and chemotherapy, the changes
compared to placebo in lean body mass and stair climb performance
observed in this study are similar in magnitude to the changes
observed in the earlier Ostarine Phase II proof of concept sarcopenia
clinical trial. We are looking forward to continuing our work with
Merck on the future development of Ostarine and other SARMs."
"We are committed to moving forward with our program on SARMs and
look forward to continuing our work with GTx," said Alan B. Ezekowitz,
MBChB, D.Phil., senior vice president and franchise head, Bone,
Respiratory, Immunology, and Endocrine, Merck Research Laboratories.
About cancer cachexia
Cancer induced muscle loss occurs in about 50 percent of cancer
patients and may lead to loss of protein stores, severe weakness and
fatigue, immobility, loss of independence, and an inability to
tolerate and respond to cancer treatments. Cancer induced muscle
wasting is responsible for at least 20 percent of cancer deaths. There
are no drugs currently approved for the treatment of cancer wasting.
About GTx
GTx, Inc., headquartered in Memphis, Tenn., is a biopharmaceutical
company dedicated to the discovery, development, and commercialization
of small molecules that selectively target hormone pathways to treat
cancer, osteoporosis and bone loss, muscle wasting and other serious
medical conditions. GTx is developing toremifene citrate, a selective
estrogen receptor modulator, or SERM, in two separate clinical
programs in men: first, a completed pivotal Phase III clinical trial
evaluating toremifene 80 mg for the treatment of estrogen deficiency
side effects of androgen deprivation therapy for advanced prostate
cancer, and second, an ongoing pivotal Phase III clinical trial
evaluating toremifene 20 mg for the prevention of prostate cancer in
high risk men with high grade prostatic intraepithelial neoplasia, or
PIN.
In 2006, GTx and Ipsen Group entered into a development and
collaboration agreement for toremifene citrate in all indications
except breast cancer for Europe and the Commonwealth of Independent
States (CIS). GTx will file for marketing approval and, if approved,
plans to commercialize toremifene 80 mg in the United States.
In December 2007, GTx and Merck & Co., Inc. formed a collaboration
to discover and develop selective androgen receptor modulators
(SARMs), a new class of drugs with the potential to treat sarcopenia,
which is the loss of skeletal muscle mass resulting in reduced
physical strength and ability to perform activities of daily living,
cancer cachexia (muscle wasting), as well as other musculoskeletal
conditions. Merck and GTx are conducting several Phase I and Phase II
clinical trials evaluating multiple SARM product candidates including
Ostarine(TM) (also designated as MK-2866) for sarcopenia. Merck and
GTx are evaluating additional muscle loss indications for potential
SARM clinical development.
GTx also is developing its preclinical compounds, GTx-758, an oral
LH inhibitor for advanced prostate cancer, and GTx-878, an estrogen
receptor beta agonist for the treatment of benign prostatic
hyperplasia and chronic prostatitis.
Forward-Looking Information is Subject to Risk and Uncertainty
This press release contains forward-looking statements based upon
GTx's current expectations. Forward-looking statements involve risks
and uncertainties. GTx's actual results and the timing of events could
differ materially from those anticipated in such forward-looking
statements as a result of these risks and uncertainties, which
include, without limitation, the risks that (i) GTx and its
collaboration partners will not be able to commercialize their product
candidates if clinical trials do not demonstrate safety and efficacy
in humans; (ii) GTx may not able to obtain required regulatory
approvals to commercialize product candidates; (iii) clinical trials
being conducted by GTx and its collaboration partners may not be
completed on schedule, or at all, or may otherwise be suspended or
terminated; and (iv) GTx could utilize its available cash resources
sooner than it currently expects and may be unable to raise capital
when needed, which would force GTx to delay, reduce or eliminate its
product development programs or commercialization efforts. You should
not place undue reliance on these forward-looking statements, which
apply only as of the date of this press release. GTx's annual report
on Form 10-K filed March 11, 2008, and its most recent Form 10-Q filed
August 5, 2008, contain under the heading, "Risk Factors," a more
comprehensive description of these and other risks to which GTx is
subject. GTx expressly disclaims any obligation or undertaking to
release publicly any updates or revisions to any forward-looking
statements contained herein to reflect any change in its expectations
with regard thereto or any change in events, conditions or
circumstances on which any such statements are based.
Source: GTx, Inc.
