EXHIBIT 99.1

Contact:
McDavid Stilwell
GTx, Inc.
Manager, Corporate Communications & Financial Analysis
901-523-9700

GTX, INC. INITIATES PHASE II CLINICAL TRIAL OF OSTARINE, A FIRST-IN-CLASS DRUG

MEMPHIS, TENN. - May 15, 2006 -- GTx, Inc. (Nasdaq: GTXI), the Men's Health
Biotech Company, announced today that it has initiated a proof of concept Phase
II clinical trial of ostarine, a first-in-class drug. The clinical trial is
designed to evaluate the ability of ostarine, a selective androgen receptor
modulator (SARM), to build muscle and to promote bone, as well as to assess its
safety in both elderly men and postmenopausal women.

"We are excited about the progress of ostarine in clinical development," said
Mitchell S. Steiner, M.D., Chief Executive Officer of GTx. "Ostarine was
discovered by GTx scientists and is the first SARM to enter Phase II clinical
testing. We are pleased to attain this important milestone."

GTx believes that with unique, tissue selective anabolic activity, ostarine has
the potential to distinguish itself from current osteoporosis drugs which only
treat bone loss. In preclinical studies, ostarine not only strengthened bone by
both building bone and preventing bone loss, but it also increased muscle.
Greater muscle mass and strength help to prevent fall-related skeletal fractures
by providing stronger support for bone and by improving a patient's balance and
gait.

Ostarine had an approximately 24 hour half-life in a single ascending dose Phase
I clinical trial in 96 healthy male volunteers. In a 14 day multiple ascending
dose Phase I clinical trial in 48 healthy male volunteers and 23 elderly men,
ostarine had positive changes on muscle without clinically detectable side
effects on the prostate or the skin.

The proof-of-concept Phase II ostarine clinical trial is a randomized, placebo
controlled, double blind, dose finding study in 60 elderly men and 60
postmenopausal women. Study participants will receive one of 4 doses of ostarine
or placebo orally each day for three months. Endpoints of the trial include
measurements of bone, fat, muscle mass, and performance.



"A positive outcome of this Phase II ostarine clinical trial would distinguish
ostarine from existing therapies for muscle and bone loss," said Steiner. "The
clinical data will determine ostarine's novel anabolic effects and tissue
selectivity. These data will support further development of ostarine for acute
muscle wasting indications such as cancer, end stage renal disease, or burn
injury wasting conditions, and for chronic indications such as osteoporosis and
age related frailty."

GTx has all rights to ostarine. GTx expects to report clinical data in the
second half of 2006.

ABOUT GTX, INC.

GTx, headquartered in Memphis, Tenn., is a biopharmaceutical company dedicated
to the discovery, development and commercialization of therapeutics for cancer
and serious conditions related to men's health. GTx's lead drug discovery and
development programs are focused on small molecules that selectively modulate
the effects of estrogens and androgens, two essential classes of hormones. GTx
is developing ACAPODENE(R) (toremifene citrate), a selective estrogen receptor
modulator, or SERM, in two separate clinical programs in men: first, a pivotal
Phase III clinical trial for the treatment of serious side effects of androgen
deprivation therapy for advanced prostate cancer, and second, a pivotal Phase
III clinical trial for the prevention of prostate cancer in high risk men with
high grade PIN. GTx also is developing ostarine, a selective androgen receptor
modulator, or SARM, for a variety of indications including muscle wasting and
bone loss in frail elderly patients, osteoporosis, muscle wasting in end stage
renal disease patients, and severe burn wounds and associated muscle wasting.
GTx has licensed to Ortho Biotech Products, L.P., a subsidiary of Johnson &
Johnson, another of its SARMs, andarine, under a joint collaboration and license
agreement.

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 will
not be able to commercialize its product candidates if clinical trials do not
demonstrate safety and efficacy in humans; (ii) GTx may not be able to obtain
required regulatory approvals to commercialize its product candidates; (iii)
GTx's clinical trials 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 Quarterly Report on Form 10-Q filed on May 5,
2006 contains 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.