Document and Entity Information	3 Months Ended
Document and Entity Information	Mar. 31, 2015	May 05, 2015
Document and Entity Information
Entity Registrant Name	GTX INC /DE/
Entity Central Index Key	0001260990
Document Type	10-Q
Document Period End Date	Mar. 31, 2015
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		140,374,112
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1

CONDENSED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 14,163	$ 17,880
Short-term investments	30,437	31,415
Prepaid expenses and other current assets	743	856
Total current assets	45,343	50,151
Property and equipment, net	16	29
Intangible and other assets, net	423	471
Total assets	45,782	50,651
Current liabilities:
Accounts payable	438	512
Warrant liability	27,782	30,430
Accrued expenses and other current liabilities	1,647	1,850
Total current liabilities	29,867	32,792
Other long-term liabilities	20	30
Commitments and contingencies
Stockholders' equity:
Common stock, $0.001 par value: 200,000,000 shares authorized at March 31, 2015 and December 31, 2014; 140,374,112 and 140,325,643 shares issued and outstanding at March 31, 2015 and December 31, 2014, respectively	140	140
Additional paid-in capital	512,910	512,460
Accumulated deficit	(497,155)	(494,771)
Total stockholders' equity	15,895	17,829
Total liabilities and stockholders' equity	$ 45,782	$ 50,651

CONDENSED BALANCE SHEETS (Parenthetical) (USD $)	Mar. 31, 2015	Dec. 31, 2014
CONDENSED BALANCE SHEETS
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	140,374,112	140,325,643
Common stock, shares outstanding	140,374,112	140,325,643

CONDENSED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Expenses:
Research and development expenses	$ 2,948	$ 6,360
General and administrative expenses	2,111	2,629
Total expenses	5,059	8,989
Loss from operations	(5,059)	(8,989)
Other income, net	27	2
Gain on change in fair value of warrant liability	2,648
Net loss	$ (2,384)	$ (8,987)
Net loss per share - basic and diluted:
Net loss per share - basic and diluted (in dollars per share)	$ (0.02)	$ (0.14)
Weighted average shares outstanding:
Basic and diluted (in shares)	140,335,875	66,512,069

CONDENSED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Cash flows from operating activities:
Net loss	$ (2,384)	$ (8,987)
Adjustments to reconcile net loss to net cash used in operating activities:
Gain on change in fair value of warrant liability	(2,648)
Depreciation and amortization	17	33
Share-based compensation	419	2,215
Directors' deferred compensation	31	32
Changes in assets and liabilities:
Prepaid expenses and other assets	157	(1,169)
Accounts payable	(74)	(189)
Accrued expenses and other liabilities	(213)	(22)
Net cash used in operating activities	(4,695)	(8,087)
Cash flows from investing activities:
Purchase of property and equipment		(4)
Purchase of short-term investments, held to maturity	(10,202)	(5,145)
Proceeds from maturities of short-term investments, held to maturity	11,180
Net cash provided by (used in) investing activities	978	(5,149)
Cash flows from financing activities:
Net proceeds from the issuance of common stock and warrants		21,141
Payments on capital lease and financed equipment obligations		(2)
Net cash provided by financing activities		21,139
Net (decrease) increase in cash and cash equivalents	(3,717)	7,903
Cash and cash equivalents, beginning of period	17,880	14,529
Cash and cash equivalents, end of period	$ 14,163	$ 22,432

Business and Basis of Presentation	3 Months Ended
Business and Basis of Presentation	Mar. 31, 2015
Business and Basis of Presentation
Business and Basis of Presentation	1. Business and Basis of Presentation Business GTx, Inc. (“GTx” or the “Company”), a Delaware corporation incorporated on September 24, 1997 and headquartered in Memphis, Tennessee, is a biopharmaceutical company dedicated to the discovery, development and commercialization of small molecules for the treatment of cancer, including treatments for breast and prostate cancer, and other serious medical conditions. The Company is developing selective androgen receptor modulators (“SARMs”), including its lead product candidate, enobosarm (GTx-024). SARMs are a new class of drugs that the Company believes have the potential to be used as a novel hormonal therapy for the treatment of advanced breast cancer, as well as the potential to treat other serious medical conditions where building lean body mass is important. The Company announced during the second quarter of 2014 positive results from an ongoing Phase 2 proof-of-concept, open-label clinical trial evaluating a 9 mg oral daily dose of enobosarm for the treatment of patients with estrogen receptor (“ER”) positive and androgen receptor (“AR”) positive metastatic breast cancer who have previously responded to hormonal therapy. The Company’s current strategy is focused on further development of enobosarm in two breast cancer indications targeting the androgen receptor. The Company plans to initiate a Phase 2 proof-of-concept clinical trial of enobosarm later in the second quarter of 2015 that is designed to evaluate the efficacy and safety of enobosarm in patients with advanced AR positive triple-negative breast cancer. The Company also plans to initiate a second Phase 2 clinical trial in the third quarter of 2015 evaluating enobosarm in patients with ER positive and AR positive advanced breast cancer. Additionally, the Company is evaluating enobosarm and other compounds in its SARM portfolio for indications outside of oncology where unmet medical needs in muscle related diseases may benefit from building muscle. In March 2015, the Company entered into an exclusive license agreement with the University of Tennessee Research Foundation (“UTRF”) to develop UTRF’s proprietary selective androgen receptor degrader, or SARD, technology which has the potential to provide compounds that can degrade multiple forms of AR for those patients who do not respond or are resistant to current therapies to inhibit tumor growth in patients with progressive castration-resistant prostate cancer (“CRPC”). The Company’s evaluation of the licensed SARD technology is at a very early stage and any future preclinical or clinical development of the SARD technology, beyond identifying potential lead clinical compounds, will require us to obtain additional funding. The Company is also developing GTx-758 (Capesaris®), an oral nonsteroidal selective ER alpha agonist, for the treatment of advanced prostate cancer. The Company is presently conducting a Phase 2 clinical trial evaluating GTx-758 as a secondary hormonal therapy in men with metastatic and high risk non-metastatic CRPC with data from this clinical trial expected in the third quarter of 2015. The Company does not plan to dedicate further resources to this program after the conclusion of this Phase 2 clinical trial and is currently determining third party interest in partnering or acquiring this asset and other preclinical ER alpha agonist compounds in order to fund additional clinical development. The Company estimates that its current cash, cash equivalents and short-term investments, together with interest thereon, will be sufficient to meet its projected operating requirements through the end of 2016 (during which time it expects, at a minimum, to obtain results from the patients enrolled in the first stage of each of our planned open-label Phase 2 clinical trials of enobosarm in patients with AR positive advanced breast cancer). Basis of Presentation The accompanying unaudited condensed financial statements reflect, in the opinion of management, all adjustments (consisting of normal recurring adjustments) necessary for a fair presentation of GTx’s financial position, results of operations and cash flows for each period presented in accordance with accounting principles generally accepted in the United States for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States have been condensed or omitted from the accompanying condensed financial statements. These interim condensed financial statements should be read in conjunction with the audited financial statements and related notes thereto, which are included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014. Operating results for the three months ended March 31, 2015 are not necessarily indicative of the results that may be expected for the entire fiscal year ending December 31, 2015. Use of Estimates The preparation of condensed financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the condensed financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual amounts and results could differ from those estimates. Warrant Liability In November 2014, the Company issued warrants to purchase 64,311,112 shares of its common stock. The Company classifies the warrants as a liability on its balance sheet since the warrants contain certain terms that could require the Company (or its successor) to purchase the warrants for cash in an amount equal to the value (as calculated utilizing a contractually-agreed Black-Scholes-Merton option pricing valuation model (“Black-Scholes Model”)) of the unexercised portion of the warrants in connection with certain change of control transactions occurring on or prior to December 31, 2016, with such cash payment capped at an amount equal to $0.125 per unexercised share underlying each warrant. In addition, each warrant was subject to net cash settlement if, at the time of any exercise, there was then an insufficient number of authorized and reserved shares of common stock to effect a share settlement of the warrant. Under the terms of the warrants, as of May 6, 2015, the net cash settlement feature of the warrants automatically became inoperative; accordingly, the warrants are exercisable only for shares of the Company’s common stock. See Subsequent Events. As a result of the provision of the warrant requiring cash settlement upon certain change of control transactions, the Company is required to account for these warrants as a liability at fair value and the estimated warrant liability is required to be revalued at each balance sheet date until the earlier of the exercise of the warrants or the expiration of the provision on December 31, 2016 that could require cash settlement upon certain change of control transactions. Upon the exercise of the warrants or the expiration of the provision on December 31, 2016 that could require cash settlement upon certain change of control transactions, the fair value of the warrants will be reclassified from a liability to stockholders’ equity on the Company’s balance sheets and no further adjustment to the fair value would be made in subsequent periods. See Note 4, Stockholders’ Equity, for further information regarding these warrants and the Company’s valuation of the warrant liability. Fair Value of Financial Instruments and Warrant Liability The carrying amounts of the Company’s financial instruments (which include cash, cash equivalents, short-term investments, and accounts payable) and its warrant liability approximate their fair values. The fair value of the warrant liability is estimated using the Black-Scholes-Merton pricing valuation model. See Note 4, Stockholders’ Equity, for additional disclosure on the valuation methodology and significant assumptions. The Company’s financial assets and liabilities are classified within a three-level fair value hierarchy that prioritizes the inputs used to measure fair value, which is defined as follows: Level 1 — Quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date Level 2 — Inputs other than quoted prices in active markets that are observable for the asset or liability, either directly or indirectly Level 3 — Inputs that are unobservable for the asset or liability Asset and liabilities measured at fair value on a recurring basis as of March 31, 2015 and December 31, 2014 included only the Company’s warrant liability of $27,782 and $30,430, respectively, which were classified within Level 3 of the hierarchy. A gain of $2,648 related to the change in the fair value of the warrant liability was recognized during the three months ended March 31, 2015 as a non-cash gain in the Company’s condensed statement of operations. As the Company has the positive intent and ability to hold its certificates of deposit classified as short-term investments until maturity, these investments have been classified as held to maturity investments and are stated at cost, which approximates fair value. The Company considers these to be Level 2 investments as the fair values of these investments are determined using third-party pricing sources, which generally utilize observable inputs, such as interest rates and maturities of similar assets. Research and Development Expenses Research and development expenses include, but are not limited to, the Company’s expenses for personnel, supplies, and facilities associated with research activities, screening and identification of product candidates, formulation and synthesis activities, manufacturing, preclinical studies, toxicology studies, clinical trials, regulatory and medical affairs activities, quality assurance activities and license fees. The Company expenses these costs in the period in which they are incurred. The Company estimates its liabilities for research and development expenses in order to match the recognition of expenses to the period in which the actual services are received. As such, accrued liabilities related to third party research and development activities are recognized based upon the Company’s estimate of services received and degree of completion of the services in accordance with the specific third party contract. As a result of the October 2013 reduction in its workforce, the Company is no longer conducting in-house drug discovery activities. Cash, Cash Equivalents and Short-term Investments The Company considers highly liquid investments with initial maturities of three months or less to be cash equivalents. At March 31, 2015 and December 31, 2014, short-term investments consisted of Federal Deposit Insurance Corporation insured certificates of deposit with original maturities of greater than three months and less than one year. Income Taxes The Company accounts for deferred taxes by recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements or tax returns. Under this method, deferred tax assets and liabilities are determined based on the difference between the financial statement and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. A valuation allowance is provided when it is more likely than not that some portion or all of the deferred tax assets will not be realized. Accordingly, at March 31, 2015 and December 31, 2014, net of the valuation allowance, the net deferred tax assets were reduced to zero. Income taxes are described more fully in Note 9 to the Company’s financial statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014. Other Income, net Other income, net consists of foreign currency transaction gains and losses associated with conducting clinical trials in foreign countries, interest earned on the Company’s cash, cash equivalents and short-term investments, interest expense, and other non-operating income or expense. Recent Accounting Pronouncements In August 2014, the Financial Accounting Standards Board issued Accounting Standard Update 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern. The new guidance is intended to define management’s responsibility to evaluate whether there is substantial doubt about an organization’s ability to continue as a going concern within one year of the date the financial statements are issued and to provide related footnote disclosure. This new guidance is effective for the first annual period ending after December 15, 2016 and interim periods thereafter. Subsequent Events The Company has evaluated all events or transactions that occurred after March 31, 2015 up through the date the condensed financial statements were issued. Other than as set forth below, there were no material recognizable or nonrecognizable subsequent events during the period evaluated. On May 6, 2015 (the “Authorized Share Increase Date”), the Company filed a Certificate of Amendment to the Company’s Restated Certificate of Incorporation with the Secretary of State of the State of Delaware to increase the number of authorized shares of the Company’s common stock, par value $0.001 per share, from 200,000,000 shares to 400,000,000 shares. The foregoing amendment was approved by the Company’s stockholders at the Company’s 2015 Annual Meeting of Stockholders held on May 6, 2015 (the “Stockholder Approval Date”). On the Stockholder Approval Date, the warrants the Company issued in November 2014 became exercisable and will continue to be exercisable for four years thereafter. Under the terms of these warrants, as of the Authorized Share Increase Date, the net cash settlement feature of the warrants automatically became inoperative; accordingly, the warrants are exercisable only for shares of the Company’s common stock. On April 13, 2015, the Company entered into a new office lease with respect to the Company’s current office space at 175 Toyota Plaza, Memphis, Tennessee (the “Office Lease”). The Office Lease commenced on May 1, 2015 with 26,250 rentable square feet and a three year term ending on April 30, 2018 (the “Initial Term”). The approximate aggregate rent due over the Initial Term is $1.4 million. Additionally, certain taxes and operating expenses may be charged to the Company beginning January 1, 2016 as additional rent based upon increases in these taxes and operating expenses after the base year, as defined in the Office Lease.

Share-Based Compensation

3 Months Ended

Mar. 31, 2015

Share-Based Compensation

Share-Based Compensation

2. Share-Based Compensation

Share-based payments include stock option grants and restricted stock units (“RSUs”) under the Company’s stock option and equity incentive plans and deferred compensation arrangements for the Company’s non-employee directors. The Company recognizes compensation expense for its share-based payments based on the fair value of the awards over the period during which an employee or non-employee director is required to provide service in exchange for the award. The Company’s share-based compensation plans are described more fully in Note 3 to the Company’s financial statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014.

The following table summarizes share-based compensation expense included within the condensed statements of operations for the three months ended March 31, 2015 and 2014:

	Three Months Ended March 31,
	2015		2014
Research and development expenses	$	189	$	1,380
General and administrative expenses	261		867
Total share-based compensation	$	450	$	2,247

Share-based compensation expense recorded as general and administrative expense for the three months ended March 31, 2015 and 2014 included share-based compensation expense related to deferred compensation arrangements for the Company’s non-employee directors of $31 and $32, respectively.

The Company uses the Black-Scholes Model to value stock options. The expected life of options is determined by calculating the average of the vesting term and the contractual term of the options. The expected price volatility is based on the Company’s historical stock price volatility. The risk-free interest rate is determined using U.S. Treasury rates where the term is consistent with the expected life of the stock options. Expected dividend yield is not considered as the Company has not made any dividend payments and has no plans of doing so in the foreseeable future. The amount of share-based compensation expense recognized is reduced ratably over the vesting period by an estimate of the percentage of options granted that are expected to be forfeited or canceled before becoming fully vested.

The fair value of options granted was estimated using the following assumptions for the periods presented:

	Three Months Ended March 31,
	2015		2014
Expected price volatility	88.5	%	87.9	%
Risk-free interest rate	2.0	%	2.3	%
Weighted average expected life in years	7 years		6.5 years

The following is a summary of stock option transactions for all of the Company’s stock option and equity incentive plans since the Company’s most recent fiscal year end:

	Number of Shares		Weighted Average Exercise Price Per Share
Options outstanding at December 31, 2014	8,104,434		$	4.24
Options granted	35,000		0.76
Options expired	(123,100	)	5.27
Options exercised	—		—
Options outstanding at March 31, 2015	8,016,334		4.21

During the three months ended March 31, 2015, the Company granted 7,700,000 RSUs to employees of which a portion of each award vests annually over a three year period from the date of grant. The Company estimates the fair value of RSUs using the closing price of its stock on the grant date. The fair value of RSUs is amortized on a straight-line basis over the requisite service period of the awards. The non-vested RSUs had a weighted average grant date fair value per share of $0.67.

- Definition

The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details.

+ References+ Details

Basic and Diluted Net Loss Per Share	3 Months Ended
Basic and Diluted Net Loss Per Share	Mar. 31, 2015
Basic and Diluted Net Loss Per Share
Basic and Diluted Net Loss Per Share	3.Basic and Diluted Net Loss Per Share Basic and diluted net loss per share attributable to common stockholders is calculated based on the weighted average number of common shares outstanding during the period. Diluted net loss per share gives effect to the dilutive potential of common stock consisting of stock options, unvested RSUs and common stock warrants. Weighted average potential shares of common stock of 83,097,046 and 10,382,571 for the three months ended March 31, 2015 and 2014, respectively, were excluded from the calculations of diluted loss per share as inclusion of the potential shares would have had an anti-dilutive effect on the net loss per share for the periods. The increase in the weighted average potential shares of common stock excluded from the calculation of diluted net loss per share increased from the prior year due to the issuance of warrants under the two financing transactions that occurred during the year ended December 31, 2014.

- Definition

The entire disclosure for earnings per share.

+ References+ Details

Stockholders' Equity	3 Months Ended
Stockholders' Equity	Mar. 31, 2015
Stockholders' Equity
Stockholders' Equity	4.Stockholders’ Equity Common Stock and Associated Warrant Liability On November 14, 2014, the Company completed a private placement of units consisting of an aggregate of 64,311,112 shares of common stock and warrants to purchase an aggregate of 64,311,112 shares of its common stock for net proceeds of $42,814, after deducting offering expenses. The purchasers in the private placement included certain existing GTx stockholders and certain members of the GTx management team and board of directors. The net proceeds from the private placement were allocated to the common stock and warrants based upon the fair value method. Similarly, the offering expenses were allocated between the common stock and warrants with the portion allocated to common stock offset against the proceeds allocated to stockholders’ equity, whereas the portion allocated to the warrants was expensed immediately. The warrants have a per share exercise price of $0.85, became exercisable on May 6, 2015 and will continue to be exercisable for four years thereafter. Prior to the Authorized Share Increase Date, each warrant was subject to net cash settlement if, at the time of any exercise, there was then an insufficient number of authorized and reserved shares of common stock to effect a share settlement of the warrant. Under the terms of the warrants, as of the Authorized Share Increase Date, the net cash settlement feature of the warrants automatically became inoperative; accordingly, the warrants are exercisable only for shares of the Company’s common stock. The warrants, however, contain certain terms that could require the Company (or its successor) to purchase the warrants for cash in an amount equal to the value (as calculated utilizing a contractually-agreed Black-Scholes-Merton pricing valuation model) of the unexercised portion of the warrants in connection with certain change of control transactions occurring on or prior to December 31, 2016, with the cash payment capped at an amount equal to $0.125 per unexercised share underlying each warrant. Due to the provision of the warrants that could require cash settlement upon certain change of control transactions, the Company is required to account for these warrants as a liability at fair value using the Black-Scholes Model and the estimated warrant liability is required to be revalued at each balance sheet date until the earlier of the exercise of the warrants or the expiration of the provision on December 31, 2016 that could require cash settlement upon certain change of control transactions. The fair value of the warrants at March 31, 2015 of $27,782 was estimated using the Black-Scholes-Merton pricing valuation model with the following assumptions: expected volatility of 95%, risk-free interest rate of 1.1%, expected life of approximately 4.1 years and no dividends. The fair value of the warrants at December 31, 2014 of $30,430 was estimated using the Black-Scholes Model with the following assumptions: expected volatility of 91%, risk-free interest rate of 1.5%, expected life of approximately 4.5 years and no dividends. The decrease in fair value from December 31, 2014 of $2,648 was recorded as a non-cash gain on the change in fair value of warrant liability in the Company’s condensed statement of operations. Significant changes to the Company’s market price for its common stock will impact the implied and/or historical volatility used to fair value the warrants. Any significant increases in the Company’s stock price will likely create an increase to the fair value of the warrant liability. Similarly, any significant decreases in the Company’s stock price will likely create a decrease to the fair value of the warrant liability. On March 6, 2014, the Company completed a private placement of units consisting of an aggregate of 11,976,048 shares of common stock and warrants to purchase an aggregate of 10,179,642 shares of its common stock for net proceeds of $21,135, after deducting offering expenses. The net proceeds from the private placement were allocated to the common stock and warrants based upon their relative fair values. The warrants, which had a one year term, expired unexercised on March 6, 2015.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29-31)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30, 31

-Article 5

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 4.E)

-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74512-122707

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 4

-Subparagraph (SAB TOPIC 4.C)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Article 4

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 4

-Section C

Reference 8: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 4

-Section E

Reference 9: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(d),(e))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 10: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Preferred Stock

-URI http://asc.fasb.org/extlink&oid=6521494

Reference 11: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 12: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 13: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 14: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

Reference 15: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 11

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21564-112644

Reference 16: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21488-112644

Reference 17: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21484-112644

Reference 18: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph d

-Article 4

Reference 19: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6405834&loc=d3e23285-112656

+ Details

University of Tennessee Research Foundation License Agreements	3 Months Ended
	Mar. 31, 2015
University of Tennessee Research Foundation License Agreements
University of Tennessee Research Foundation License Agreements	5.University of Tennessee Research Foundation License Agreements The Company and the University of Tennessee Research Foundation (“UTRF”) are parties to a consolidated, amended and restated license agreement (the “SARM License Agreement”) pursuant to which the Company was granted exclusive worldwide rights in all existing SARM technologies owned or controlled by UTRF, including all improvements thereto, and exclusive rights to future SARM technology that may be developed by certain scientists at the University of Tennessee or subsequently licensed to UTRF under certain existing inter-institutional agreements with The Ohio State University. Under the SARM License Agreement, the Company is obligated to pay UTRF annual license maintenance fees, low single-digit royalties on net sales of products and mid-single-digit royalties on sublicense revenues. The Company and UTRF also entered into a license agreement (the “SARD License Agreement”) in March 2015 pursuant to which the Company was granted exclusive worldwide rights in all existing SARD technologies owned or controlled by UTRF, including all improvements thereto. Under the SARD License Agreement, the Company is obligated to employ active, diligent efforts to conduct preclinical research and development activities for the SARD program to advance one or more lead compounds into clinical development. The Company is also obligated to pay UTRF annual license maintenance fees, low single-digit royalties on net sales of products and additional royalties on sublicense revenues, depending on the state of development of a clinical product candidate at the time it is sublicensed.

Business and Basis of Presentation (Policies)	3 Months Ended
Business and Basis of Presentation (Policies)	Mar. 31, 2015
Business and Basis of Presentation
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed financial statements reflect, in the opinion of management, all adjustments (consisting of normal recurring adjustments) necessary for a fair presentation of GTx’s financial position, results of operations and cash flows for each period presented in accordance with accounting principles generally accepted in the United States for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States have been condensed or omitted from the accompanying condensed financial statements. These interim condensed financial statements should be read in conjunction with the audited financial statements and related notes thereto, which are included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014. Operating results for the three months ended March 31, 2015 are not necessarily indicative of the results that may be expected for the entire fiscal year ending December 31, 2015.
Use of Estimates	Use of Estimates The preparation of condensed financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the condensed financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual amounts and results could differ from those estimates.
Warrant Liability	Warrant Liability In November 2014, the Company issued warrants to purchase 64,311,112 shares of its common stock. The Company classifies the warrants as a liability on its balance sheet since the warrants contain certain terms that could require the Company (or its successor) to purchase the warrants for cash in an amount equal to the value (as calculated utilizing a contractually-agreed Black-Scholes-Merton option pricing valuation model (“Black-Scholes Model”)) of the unexercised portion of the warrants in connection with certain change of control transactions occurring on or prior to December 31, 2016, with such cash payment capped at an amount equal to $0.125 per unexercised share underlying each warrant. In addition, each warrant was subject to net cash settlement if, at the time of any exercise, there was then an insufficient number of authorized and reserved shares of common stock to effect a share settlement of the warrant. Under the terms of the warrants, as of May 6, 2015, the net cash settlement feature of the warrants automatically became inoperative; accordingly, the warrants are exercisable only for shares of the Company’s common stock. See Subsequent Events. As a result of the provision of the warrant requiring cash settlement upon certain change of control transactions, the Company is required to account for these warrants as a liability at fair value and the estimated warrant liability is required to be revalued at each balance sheet date until the earlier of the exercise of the warrants or the expiration of the provision on December 31, 2016 that could require cash settlement upon certain change of control transactions. Upon the exercise of the warrants or the expiration of the provision on December 31, 2016 that could require cash settlement upon certain change of control transactions, the fair value of the warrants will be reclassified from a liability to stockholders’ equity on the Company’s balance sheets and no further adjustment to the fair value would be made in subsequent periods. See Note 4, Stockholders’ Equity, for further information regarding these warrants and the Company’s valuation of the warrant liability.
Fair Value of Financial Instruments and Warrant Liability	Fair Value of Financial Instruments and Warrant Liability The carrying amounts of the Company’s financial instruments (which include cash, cash equivalents, short-term investments, and accounts payable) and its warrant liability approximate their fair values. The fair value of the warrant liability is estimated using the Black-Scholes-Merton pricing valuation model. See Note 4, Stockholders’ Equity, for additional disclosure on the valuation methodology and significant assumptions. The Company’s financial assets and liabilities are classified within a three-level fair value hierarchy that prioritizes the inputs used to measure fair value, which is defined as follows: Level 1 — Quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date Level 2 — Inputs other than quoted prices in active markets that are observable for the asset or liability, either directly or indirectly Level 3 — Inputs that are unobservable for the asset or liability Asset and liabilities measured at fair value on a recurring basis as of March 31, 2015 and December 31, 2014 included only the Company’s warrant liability of $27,782 and $30,430, respectively, which were classified within Level 3 of the hierarchy. A gain of $2,648 related to the change in the fair value of the warrant liability was recognized during the three months ended March 31, 2015 as a non-cash gain in the Company’s condensed statement of operations. As the Company has the positive intent and ability to hold its certificates of deposit classified as short-term investments until maturity, these investments have been classified as held to maturity investments and are stated at cost, which approximates fair value. The Company considers these to be Level 2 investments as the fair values of these investments are determined using third-party pricing sources, which generally utilize observable inputs, such as interest rates and maturities of similar assets.
Research and Development Expenses	Research and Development Expenses Research and development expenses include, but are not limited to, the Company’s expenses for personnel, supplies, and facilities associated with research activities, screening and identification of product candidates, formulation and synthesis activities, manufacturing, preclinical studies, toxicology studies, clinical trials, regulatory and medical affairs activities, quality assurance activities and license fees. The Company expenses these costs in the period in which they are incurred. The Company estimates its liabilities for research and development expenses in order to match the recognition of expenses to the period in which the actual services are received. As such, accrued liabilities related to third party research and development activities are recognized based upon the Company’s estimate of services received and degree of completion of the services in accordance with the specific third party contract. As a result of the October 2013 reduction in its workforce, the Company is no longer conducting in-house drug discovery activities.
Cash, Cash Equivalents and Short-term Investments	Cash, Cash Equivalents and Short-term Investments The Company considers highly liquid investments with initial maturities of three months or less to be cash equivalents. At March 31, 2015 and December 31, 2014, short-term investments consisted of Federal Deposit Insurance Corporation insured certificates of deposit with original maturities of greater than three months and less than one year.
Income Taxes	Income Taxes The Company accounts for deferred taxes by recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements or tax returns. Under this method, deferred tax assets and liabilities are determined based on the difference between the financial statement and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. A valuation allowance is provided when it is more likely than not that some portion or all of the deferred tax assets will not be realized. Accordingly, at March 31, 2015 and December 31, 2014, net of the valuation allowance, the net deferred tax assets were reduced to zero. Income taxes are described more fully in Note 9 to the Company’s financial statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014.
Other Income, net	Other Income, net Other income, net consists of foreign currency transaction gains and losses associated with conducting clinical trials in foreign countries, interest earned on the Company’s cash, cash equivalents and short-term investments, interest expense, and other non-operating income or expense.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In August 2014, the Financial Accounting Standards Board issued Accounting Standard Update 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern. The new guidance is intended to define management’s responsibility to evaluate whether there is substantial doubt about an organization’s ability to continue as a going concern within one year of the date the financial statements are issued and to provide related footnote disclosure. This new guidance is effective for the first annual period ending after December 15, 2016 and interim periods thereafter.
Subsequent Events	Subsequent Events The Company has evaluated all events or transactions that occurred after March 31, 2015 up through the date the condensed financial statements were issued. Other than as set forth below, there were no material recognizable or nonrecognizable subsequent events during the period evaluated. On May 6, 2015 (the “Authorized Share Increase Date”), the Company filed a Certificate of Amendment to the Company’s Restated Certificate of Incorporation with the Secretary of State of the State of Delaware to increase the number of authorized shares of the Company’s common stock, par value $0.001 per share, from 200,000,000 shares to 400,000,000 shares. The foregoing amendment was approved by the Company’s stockholders at the Company’s 2015 Annual Meeting of Stockholders held on May 6, 2015 (the “Stockholder Approval Date”). On the Stockholder Approval Date, the warrants the Company issued in November 2014 became exercisable and will continue to be exercisable for four years thereafter. Under the terms of these warrants, as of the Authorized Share Increase Date, the net cash settlement feature of the warrants automatically became inoperative; accordingly, the warrants are exercisable only for shares of the Company’s common stock. On April 13, 2015, the Company entered into a new office lease with respect to the Company’s current office space at 175 Toyota Plaza, Memphis, Tennessee (the “Office Lease”). The Office Lease commenced on May 1, 2015 with 26,250 rentable square feet and a three year term ending on April 30, 2018 (the “Initial Term”). The approximate aggregate rent due over the Initial Term is $1.4 million. Additionally, certain taxes and operating expenses may be charged to the Company beginning January 1, 2016 as additional rent based upon increases in these taxes and operating expenses after the base year, as defined in the Office Lease.

Share-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2015

Share-Based Compensation

Summary of share-based compensation expense

	Three Months Ended March 31,
	2015		2014
Research and development expenses	$	189	$	1,380
General and administrative expenses	261		867
Total share-based compensation	$	450	$	2,247

Schedule of assumptions used to estimate fair value of options

	Three Months Ended March 31,
	2015		2014
Expected price volatility	88.5	%	87.9	%
Risk-free interest rate	2.0	%	2.3	%
Weighted average expected life in years	7 years		6.5 years

Summary of stock option transactions

	Number of Shares		Weighted Average Exercise Price Per Share
Options outstanding at December 31, 2014	8,104,434		$	4.24
Options granted	35,000		0.76
Options expired	(123,100	)	5.27
Options exercised	—		—
Options outstanding at March 31, 2015	8,016,334		4.21

Business and Basis of Presentation (Details) (USD $)	3 Months Ended			3 Months Ended		0 Months Ended			0 Months Ended
Business and Basis of Presentation (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Nov. 14, 2014	Mar. 31, 2015 Fair Value Measurements, Recurring Level 3	Dec. 31, 2014 Fair Value Measurements, Recurring Level 3	May 06, 2015 Subsequent Events	May 06, 2015 Subsequent Events	May 05, 2015 Subsequent Events	Apr. 13, 2015 Subsequent Events Office Lease	Apr. 13, 2015 Subsequent Events Office Lease sqft
Warrant Liability
Warrants issued to purchase shares under private placement			64,311,112
Maximum contingent per share cash settlement price (in dollars per share)			$ 0.125
Warrant liability	$ 27,782,000	$ 30,430,000		$ 27,782,000	$ 30,430,000
Gain on change in fair value of warrant liability	2,648,000			2,648,000
Income Taxes
Net deferred tax assets	0	0
Common Stock
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001					$ 0.001
Common stock, shares authorized	200,000,000	200,000,000					400,000,000	200,000,000
Warrant term						4 years
Office lease
Rentable space on lease										26,250
Initial term of lease arrangement									3 years
Aggregate rent due over initial term										$ 1,400,000

Share-Based Compensation (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Share-based compensation expense
Total share-based compensation	$ 450	$ 2,247
Share-based compensation expense related to deferred compensation arrangements for non-employee directors	31	32
Research and development expenses
Share-based compensation expense
Total share-based compensation	189	1,380
General and administrative expenses
Share-based compensation expense
Total share-based compensation	261	867
Director \| General and administrative expenses
Share-based compensation expense
Share-based compensation expense related to deferred compensation arrangements for non-employee directors	$ 31	$ 32

Share-Based Compensation (Details 2) (USD $)	3 Months Ended
Share-Based Compensation (Details 2) (USD $)	Mar. 31, 2015	Mar. 31, 2014
Fair value of options granted
Expected price volatility (as a percent)	88.50%	87.90%
Risk-free interest rate (as a percent)	2.00%	2.30%
Weighted average expected life in years	7 years	6 years 6 months
Number of Shares
Options outstanding at the beginning of the period (in shares)	8,104,434
Options granted (in shares)	35,000
Options expired (in shares)	(123,100)
Options outstanding at the end of the period (in shares)	8,016,334
Weighted Average Exercise Price Per Share
Options outstanding at the beginning of the period (in dollars per share)	$ 4.24
Options granted (in dollars per share)	$ 0.76
Options expired (in dollars per share)	$ 5.27
Options outstanding at the end of the period (in dollars per share)	$ 4.21

Share-Based Compensation (Details 3) (Restricted Stock Units (RSUs), USD $)	3 Months Ended
	Mar. 31, 2015
Restricted Stock Units (RSUs)
Number of Shares
Restricted stock units granted (in shares)	7,700,000
Restricted stock units vesting period	3 years
Weighted Average Grant Date Fair Value Per Share
Weighted average grant date fair value per share (in dollars per share)	$ 0.67

Basic and Diluted Net Loss Per Share (Details)-10Q	3 Months Ended
Basic and Diluted Net Loss Per Share (Details)-10Q	Mar. 31, 2015	Mar. 31, 2014
Basic and Diluted Net Loss Per Share
Weighted average potential shares of common stock excluded from calculation of diluted net loss per share	83,097,046	10,382,571

- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References+ Details

Stockholders' Equity (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended			0 Months Ended	3 Months Ended	12 Months Ended		0 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Nov. 14, 2014	Nov. 14, 2014 Private Placement, November 2014	Mar. 31, 2015 Private Placement, November 2014	Dec. 31, 2014 Private Placement, November 2014	Nov. 14, 2014 Private Placement, November 2014	Mar. 06, 2014 Private Placement, March 2014	Mar. 06, 2014 Private Placement, March 2014
Common Stock and Associated Warrant Liability
Shares issued				64,311,112				11,976,048
Warrants issued to purchase shares under private placement			64,311,112				64,311,112		10,179,642
Net cash proceeds from public offering after deducting underwriting discounts and commissions and other offering expenses				$ 42,814				$ 21,135
Exercise price (in dollars per share)							$ 0.85
Warrant term				4 years				1 year
Maximum contingent per share cash settlement price (in dollars per share)			$ 0.125				$ 0.125
Fair value of warrant liability	27,782	30,430			27,782	30,430
Expected volatility of warrants (as a percent)					95.00%	91.00%
Risk free interest rate of warrants (as a percent)					1.10%	1.50%
Expected life of warrants					4 years 1 month 6 days	4 years 6 months
Expected dividends on warrants					$ 0	$ 0
Gain on change in fair value of warrant liability	$ 2,648				$ 2,648