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                                                                   EXHIBIT 10.12

                            INDEMNIFICATION AGREEMENT

         THIS AGREEMENT is made and entered into as of the ____ day of
_____________, 2003, by and between GTx, INC., a Delaware corporation (the
"Company"), and the undersigned (the "Indemnitee").

                                    RECITALS

         WHEREAS, it is essential to the Company that it attract and retain as
directors and officers the most capable persons available; and

         WHEREAS, both the Company and Indemnitee recognize the increased risk
of litigation and other claims being asserted against directors and officers of
public companies in the current environment; and

         WHEREAS, the prohibitive cost and limited coverages associated with
insurance and the uncertainties relating to indemnification have increased the
difficulty of attracting and retaining qualified persons to serve as corporate
officers and directors; and

         WHEREAS, the Indemnitee currently is serving as a director or officer
of the Company, and the Company desires that the Indemnitee continue to serve in
such capacity. The Indemnitee is willing to continue to serve in such capacity
if the Indemnitee is adequately protected against the risks associated with such
service; and

         WHEREAS, Section 145 of the General Corporation Law of the State of
Delaware (the "DGCL"), under which law the Company is organized, empowers a
corporation to indemnify a person serving as a director or officer of the
Company and a person who serves at the request of the Company as a director,
officer, employee or agent of another corporation, partnership, joint venture,
trust, or other enterprise, and Section 145 of the DGCL and the Certificate of
Incorporation of the Company specify that the indemnification set forth in
Section 145 and in the Certificate of Incorporation, respectively, shall not be
deemed exclusive of any other rights to which those seeking indemnification may
be entitled under any law (common or statutory), agreement, vote of stockholders
or Disinterested Directors (defined below) or otherwise; and

         WHEREAS, the Company and the Indemnitee have concluded that the
indemnities available under the Company's Certificate of Incorporation, Bylaws
and any insurance now or hereafter in effect need to be supplemented to more
fully protect the Indemnitee against the risks associated with the Indemnitee's
service to the Company; and

         WHEREAS, in recognition of Indemnitee's need for additional protection
against personal liability in order to enhance Indemnitee's continued service to
the Company in an effective manner, and in order to induce Indemnitee to
continue to provide services to the Company as a director or officer thereof,
the Company wishes to provide in this Agreement for the indemnification of
Indemnitee to the fullest extent permitted by law and as set forth in this
Agreement.
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         NOW THEREFORE, in consideration of the foregoing and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the covenants contained herein and Indemnitee's continued service
to the Company, the Company and Indemnitee, intending to be legally bound,
hereby agree as follows:

         Section 1.        Definitions. The following terms, as used herein,
shall have the following respective meanings:

         "Affiliate" of any specified Person means any other Person directly or
indirectly controlling or controlled by or under direct or indirect common
control with such specified Person. For the purposes of this definition,
"control" when used with respect to any specified Person means the power to
direct the management and policies of such Person, directly or indirectly,
whether through the ownership of voting securities, by contract or otherwise;
and the terms "controlling" and "controlled" have meanings relative to the
foregoing.

         "Change in Control" shall be deemed to have taken place if: (i) any
person or entity, including a "group" as defined in Section 13(d)(3) of the
Securities Exchange Act of 1934, as amended (the "Exchange Act") other than the
Company or a wholly-owned subsidiary thereof or any employee benefit plan of the
Company or any of its subsidiaries, becomes the beneficial owner of Company
securities having 50% or more of the combined voting power of the then
outstanding securities of the Company that may be cast for the election of
directors of the Company (other than as a result of an issuance of securities
initiated by the Company in the ordinary course of business); or (ii) as the
result of, or in connection with, any cash tender or exchange offer, merger or
other business combination, sale of substantially all of the assets or contested
election, or any combination of the foregoing transactions, less than a majority
of the combined voting power of the then-outstanding securities of the Company
or any successor corporation or entity entitled to vote generally in the
election of the directors of the Company or such other corporation or entity
after such transaction is held in the aggregate by the holders of the Company
securities entitled to vote generally in the election of directors of the
Company immediately prior to such transaction; or (iii) during any period of two
consecutive years, individuals who at the beginning of any such period
constitute the Board of Directors of the Company cease for any reason to
constitute at least a majority thereof, unless the election, or the nomination
for election by the Company's stockholders, of each director of the Company
first elected during such period was approved by the Nominating Committee,
Corporate Governance Committee or similar committee of the Board of Directors.

         "Claim" means (a) any threatened, pending or completed action, suit,
proceeding or arbitration or other alternative dispute resolution mechanism, or
(b) any inquiry, hearing or investigation, whether conducted by the Company or
any other Person, that Indemnitee in good faith believes might lead to the
institution of any such action, suit, proceeding or arbitration or other
alternative dispute resolution mechanism, in each case whether civil, criminal,
administrative or other (whether or not the claims or allegations therein are
groundless, false or fraudulent) and includes, without limitation, those brought
by or in the name of the Company or any director or officer of the Company.

         "Company" has the meaning set forth in the preface above.

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         "Company Agent" means any director, officer, partner, employee, agent,
trustee or fiduciary of the Company, any Subsidiary or any Other Enterprise.

         "Covered Event" means any event or occurrence on or after the date of
this Agreement related to the fact that Indemnitee is or was a Company Agent or
related to anything done or not done by Indemnitee in any such capacity, and
includes, without limitation, any such event or occurrence (a) arising from
performance of the responsibilities, obligations or duties imposed by ERISA or
any similar applicable provisions of state or common law, or (b) arising from
any merger, consolidation or other business combination involving the Company,
any Subsidiary or any Other Enterprise, including, without limitation, any sale
or other transfer of all or substantially all of the business or assets of the
Company, any Subsidiary or any Other Enterprise; provided, however, that in any
such case, Indemnitee acted in good faith and in a manner which Indemnitee
reasonably believed to be in or not opposed to the best interests of the
Company, and in addition, in the case of a criminal proceeding, had no
reasonable cause to believe that such Indemnitee's conduct was unlawful.

         "DGCL" has the meaning set forth in the recitals above.

         "D&O Insurance" means the directors' and officers' liability insurance
maintained by or for the benefit of the Company, its directors or officers and
any replacement or substitute policies.

         "Determination" means a determination made by (a) a majority vote of
Disinterested Directors even if less than a quorum of the entire Board of
Directors of the Company; (b) Independent Legal Counsel, in a written opinion
addressed to the Company and Indemnitee; (c) the stockholders of the Company; or
(d) a decision by a court of competent jurisdiction not subject to further
appeal.

         "Disinterested Director" shall be a director of the Company who is not
or was not a party to the Claim giving rise to the subject matter of a
Determination.

         "Exchange Act" has the meaning set forth in the definition of Change of
Control.

         "Expenses" includes attorneys' fees and all other costs, travel
expenses, fees of experts, transcript costs, filing fees, witness fees,
telephone charges, postage, copying costs, delivery service fees and other
expenses and obligations of any nature whatsoever paid or incurred in connection
with investigating, prosecuting or defending, being a witness in or
participating in (including on appeal), or preparing to prosecute or defend, be
a witness in or participate in any Claim, for which Indemnitee is or becomes
legally obligated to pay.

         "Indemnitee" has the meaning set forth in the preface above.

         "Independent Legal Counsel" shall mean a law firm or a member of a law
firm that (a) neither is, nor in the past five years has been, retained to
represent in any material matter the Company, any Subsidiary, any Other
Enterprise, Indemnitee or any other party to the Claim, (b)

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under applicable standards of professional conduct then prevailing would not
have a conflict of interest in representing either the Company or Indemnitee in
an action to determine Indemnitee's rights to indemnification under this
Agreement and (c) is reasonably acceptable to the Company and Indemnitee.

         "Loss" means any amount which Indemnitee is legally obligated to pay as
a result of any Claim, including, without limitation, (a) all judgments,
penalties and fines, and amounts paid or to be paid in settlement, (b) all
interest, assessments and other charges paid or payable in connection therewith
and (c) any federal, state, local or foreign taxes imposed (net of the value to
Indemnitee of any tax benefits resulting from tax deductions or otherwise as a
result of the actual or deemed receipt of any payments under this Agreement.

         "Other Enterprise" means any corporation (other than the Company or any
Subsidiary), partnership, joint venture, association, employee benefit plan,
trust or other enterprise or organization to which Indemnitee renders service at
the request of the Company or any Subsidiary.

         "Parent" shall have the meaning set forth in the regulations of the
Securities and Exchange Commission under the Securities Act of 1933, as amended
(the "Securities Act"); provided the term "Parent" shall not include the board
of directors of a corporation in its capacity as a board of directors, and
provided further that if the other party to any transaction referred to in
Section 12.1.2 has no Parent as so defined above, "Parent" shall mean such other
party.

         "Person" means any individual, corporation, partnership, joint venture,
association, joint-stock company, trust, unincorporated organization or
government (or any subdivision, department, commission or agency thereof), and
includes without limitation any "person", as such term is used in Sections 13(d)
and 14(d) of the Exchange Act.

         "Potential Change in Control" shall be deemed to have occurred if (a)
the Company enters into an agreement or arrangement the consummation of which
would result in the occurrence of a Change in Control, (b) any Person (including
the Company) publicly announces an intention to take or to consider taking
actions which if consummated would constitute a Change in Control or (c) the
Board of Directors of the Company adopts a resolution to the effect that, for
purposes of this Agreement, a Potential Change in Control has occurred.

         "Securities Act" has the meaning set forth in the definition of Parent.

         "Subsidiary" means any corporation of which more than 50% of the
outstanding stock having ordinary voting power to elect a majority of the board
of directors of such corporation is now or hereafter owned, directly or
indirectly, by the Company.

         "Voting Securities" means any securities of the Company which vote
generally in the election of directors.

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         Section 2.        Indemnification

         2.1.     General Indemnity Obligation.

                  2.1.1.   Subject to the remaining provisions of this
Agreement, the Company hereby indemnifies and holds Indemnitee harmless for any
Losses or Expenses arising from any Claims relating to (or arising in whole or
in part out of) any Covered Event, including, without limitation, any Claim the
basis of which is any actual or alleged breach of duty, neglect, error,
misstatement, misleading statement, omission or other act done or attempted by
Indemnitee in the capacity as a Company Agent, whether or not Indemnitee is
acting or serving in such capacity at the date of this Agreement, at the time
liability is incurred or at the time the Claim is initiated.

                  2.1.2.   The obligations of the Company under this Agreement
shall apply to the fullest extent authorized or permitted by the provisions of
applicable law, as presently in effect or as changed after the date of this
Agreement, whether by statute or judicial decision (but, in the case of any
subsequent change, only to the extent that such change permits the Company to
provide broader indemnification than permitted prior to giving effect thereto).

                  2.1.3.   Indemnitee shall not be entitled to indemnification
pursuant to this Agreement in connection with any Claim initiated by Indemnitee
against the Company or any director or officer of the Company, unless the
Company has joined in or consented to the initiation of such Claim; provided,
the provisions of this Section 2.1.3 shall not apply (i) following a Change in
Control to Claims seeking enforcement of this Agreement, the Certificate of
Incorporation or Bylaws of the Company or any other agreement now or hereafter
in effect relating to indemnification for Covered Events or (ii) absent a Change
in Control, to Claims seeking enforcement of this Agreement, the Certificate of
Incorporation or Bylaws of the Company or any other agreement now or hereafter
in effect relating to indemnification for Covered Events, but only if the
Indemnitee is ultimately determined to be entitled to indemnification.

                  2.1.4.   If Indemnitee is entitled under any provision of this
Agreement to indemnification by the Company for some or a portion of the Losses
or Expenses paid with respect to a Claim but not, however, for the total amount
thereof, the Company shall nevertheless indemnify and hold Indemnitee harmless
against the portion thereof to which Indemnitee is entitled.

                  2.1.5.   Notwithstanding any other provision of this
Agreement, to the extent that Indemnitee has been successful on the merits or
otherwise in defense of any or all Claims relating to (or arising in whole or in
part out of) a Covered Event or in defense of any issue or matter therein,
including dismissal without prejudice, the Company shall indemnify and hold
Indemnitee harmless against all Expenses incurred in connection therewith.

         2.2.     Indemnification for Serving as Witness and Certain Other
Claims. Notwithstanding any other provision of this Agreement, the Company
hereby indemnifies and holds Indemnitee harmless for all Expenses in connection
with (a) the preparation to serve or

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service as a witness in any Claim in which Indemnitee is not a party, if such
actual or proposed service as a witness arose by reason of Indemnitee having
served as a Company Agent on or after the date of this Agreement and (b) any
Claim initiated by Indemnitee on or after the date of this Agreement (i) for
recovery under any D&O Insurance; (ii) following a Change in Control, for
enforcement of the indemnification obligations of the Company under this
Agreement, the Certificate of Incorporation or Bylaws of the Company or any
other agreement now or hereafter in effect relating to indemnification for
Covered Events, regardless of whether Indemnitee ultimately is determined to be
entitled to such insurance recovery or indemnification, as the case may be; or
(iii) absent a Change in Control, for enforcement of this Agreement, the
Certificate of Incorporation or Bylaws of the Company or any other agreement now
or hereafter in effect relating to indemnification for Covered Events, but only
if the Indemnitee is ultimately determined to be entitled to indemnification.

         Section 3.        Limitations on Indemnification.

         3.1.     Coverage Limitations. No indemnification is available pursuant
to the provisions of this Agreement:

                  3.1.1.   If such indemnification is not lawful (and, in this
respect, both the Company and Indemnitee have been advised that the Securities
and Exchange Commission believes that indemnification for liabilities arising
under the federal securities laws is against public policy and is, therefore,
unenforceable and that claims for indemnification should be submitted to
appropriate courts for adjudication);

                  3.1.2.   If Indemnitee's conduct giving rise to the Claim with
respect to which indemnification is requested was knowingly fraudulent, a
knowing violation of law, deliberately dishonest or in bad faith or constituted
willful misconduct;

                  3.1.3.   In respect of any Claim based upon or attributable to
Indemnitee's conduct that is established by a final judgment as constituting a
breach of Indemnitee's duty of loyalty to the Company or resulting in any
personal profit or advantage to which Indemnitee was not legally entitled;

                  3.1.4.   In respect of any Claim based upon or in connection
with a proceeding by or in the right of the Company in which Indemnitee was
adjudged liable to the Company unless and only to the extent that the Court of
Chancery of Delaware shall determine upon application that, despite the
adjudication of such liability but in view of all circumstances of the case, the
Indemnitee is fairly and reasonably entitled to indemnity for such expenses
(including attorney's fees) which the Court of Chancery of Delaware shall deem
proper; or

                  3.1.5.   In respect of any Claim against Indemnitee for an
accounting of profits made from the purchase or sale by Indemnitee of securities
of the Company within the meaning of Section 16(b) of the Exchange Act or
similar provisions of any federal, state or local statutory law.

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                  3.1.6.   No Duplication of Payments. The Company shall not be
liable under this Agreement to make any payment otherwise due and payable to the
extent Indemnitee has otherwise actually received payment (whether under the
Certificate of Incorporation or the Bylaws of the Company, the D&O Insurance or
otherwise) of any amounts otherwise due and payable under this Agreement.

         Section 4.        Payments and Determinations.

         4.1.     Advancement and Reimbursement of Expenses. If requested by
Indemnitee, the Company shall advance to Indemnitee, no later than five business
days following any such request, any and all Expenses for which indemnification
is available under Section 2. In order to obtain such advancement or
reimbursement, the Indemnitee must also furnish to the Company a written
affirmation of his good faith belief that he has conducted himself in good faith
and that he reasonably believed that: (1) in the case of conduct in his official
capacity with the Company, that his conduct was in its best interest; (2) in all
other cases, that his conduct was at least not opposed to its best interests;
and (3) in the case of any criminal proceeding, he had no reasonable cause to
believe his conduct was unlawful. In addition, Indemnitee must furnish to the
Company a written undertaking, executed personally or on his behalf, to repay
the advance if it is ultimately determined that he is not entitled to
indemnification. Upon any Determination that Indemnitee is not permitted to be
indemnified for any Expenses so advanced, Indemnitee hereby agrees to reimburse
the Company for all such amounts previously paid. Such obligation of
reimbursement shall be unsecured and no interest shall be charged thereon.

         4.2.     Determination of Entitlement to Indemnification and Payment
Procedures.

                  4.2.1.   Except as provided in Section 4.1 with respect to
advances of Expenses, to obtain indemnification under this Agreement, Indemnitee
shall submit to the Company a written request, together with such documentation
and information as is reasonably available to Indemnitee and is reasonably
necessary to determine whether and to what extent Indemnitee is entitled to
indemnification. The Secretary of the Company shall, promptly upon receipt of
such a request for indemnification, advise the Board of Directors in writing
that Indemnitee has requested indemnification.

                  4.2.2.   Any such indemnification shall be made promptly, and
in any event within 60 days after receipt by the Company of the written request
of the Indemnitee, unless with respect to requests submitted pursuant to this
Agreement the Company makes a Determination within the 60 day period that the
Indemnitee did not meet the applicable standard of conduct as set forth in this
Agreement. Such Determination shall be made in the specific case (a) if a Change
in Control shall have occurred, as provided in Section 9.1; and (b) if a Change
in Control shall not have occurred, by (i) the Board of Directors by a majority
vote of Disinterested Directors, (ii) Independent Legal Counsel, if either (A)
there are no Disinterested Directors or (B) a majority vote of Disinterested
Directors otherwise so directs or (iii) the stockholders of the Company (if
submitted by the Board of Directors), but shares of stock owned by or voted
under the control of any Indemnitee who is at the time party to the proceeding
may not be voted.

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                  4.2.3.   If no Determination is made within 60 days after
receipt by the Company of a request for indemnification by Indemnitee pursuant
to Section 4.2.1, a Determination shall be deemed to have been made that
Indemnitee is entitled to the requested indemnification (and the Company shall
promptly pay the related Losses and Expenses), except where such indemnification
is not lawful; provided, however, that (a) such 60-day period may be extended
for a reasonable time, not to exceed an additional 30 days, if the Person or
Persons making the Determination in good faith require such additional time for
obtaining or evaluating the documentation and information relating thereto; and
(b) the foregoing provisions of this Section 4.2.3 shall not apply (i) if the
Determination is to be made by the stockholders of the Company and if (A) within
15 days after receipt by the Company of the request by Indemnitee pursuant to
Section 4.2.1 the Board of Directors has resolved to submit such Determination
to the stockholders at an annual meeting of the stockholders to be held within
75 days after such receipt, and such Determination is made at such annual
meeting, or (B) a special meeting of stockholders is called within 15 days after
such receipt for the purpose of making such Determination, such meeting is held
for such purpose within 60 days after having been so called and such
Determination is made at such special meeting, or (ii) if the Determination is
to be made by Independent Legal Counsel.

         Section 5.        D & O Insurance.

         5.1.     Current Policies. The Company hereby represents and warrants
to Indemnitee that Exhibit 1 contains a complete and accurate description of the
D&O Insurance and that such insurance is in full force and effect.

         5.2.     Continued Coverage. The Company shall maintain, to the extent
practicable, the D&O Insurance for so long as this Agreement remains in effect.
The Company shall cause the D&O Insurance to cover Indemnitee, in accordance
with its terms and at all times such insurance is in effect, to the maximum
extent of the coverage provided thereby for any director or officer of the
Company.

         5.3.     Indemnification. In the event of any reduction in, or
cancellation of, the D&O Insurance (whether voluntary or involuntary on behalf
of the Company), the Company shall, and hereby agrees to, indemnify and hold
Indemnitee harmless against any Losses or Expenses which Indemnitee is or
becomes obligated to pay as a result of the Company's failure to maintain the
D&O Insurance in effect in accordance with the provisions of Section 5.2, to the
fullest extent permitted by applicable law, notwithstanding any provision of the
Certificate of Incorporation or the Bylaws of the Company, or any other
agreement now or hereafter in effect relating to indemnification for Covered
Events. The indemnification available under this Section 5.3 is in addition to
all other obligations of indemnification of the Company under this Agreement and
shall be the only remedy of Indemnitee for a breach by the Company of its
obligations set forth in Section 5.2.

         Section 6.        Subrogation. In the event of any payment under this
Agreement to or on behalf of Indemnitee, the Company shall be subrogated to the
extent of such payment to all of the rights of recovery of Indemnitee against
any Person other than the Company or Indemnitee in respect of the Claim giving
rise to such payment. Indemnitee shall execute all papers reasonably

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required and shall do everything reasonably necessary to secure such rights,
including the execution of such documents reasonably necessary to enable the
Company effectively to bring suit to enforce such rights.

         Section 7.        Notification and Defense of Claims.

         7.1.     Notice by Indemnitee. Indemnitee shall give notice in writing
to the Company as soon as practicable after Indemnitee becomes aware of any
Claim with respect to which indemnification will or could be sought under this
Agreement; provided the failure of Indemnitee to give such notice, or any delay
in giving such notice, shall not relieve the Company of its obligations under
this Agreement except to the extent the Company is actually prejudiced by any
such failure or delay.

         7.2.     Insurance. The Company shall give prompt notice of the
commencement of any Claim relating to Covered Events to the insurers on the D&O
Insurance, if any, in accordance with the procedures set forth in the respective
policies in favor of Indemnitee. The Company shall thereafter take all necessary
action to cause such insurers to pay, on behalf of Indemnitee, all amounts
payable as a result of such Claims in accordance with the terms of such
policies.

         7.3.     Defense.

                  7.3.1.   In the event any Claim relating to Covered Events is
by or in the right of the Company, Indemnitee may, at the option of Indemnitee,
either control the defense thereof or accept the defense provided under the D&O
Insurance; provided, however, that Indemnitee may not control the defense if
such decision would jeopardize the coverage provided by the D&O Insurance, if
any, to the Company or the other directors and officers covered thereby, and
also provided that the amounts expended by the Company shall be reimbursed to
the Company by the Indemnitee if the standards and requirements of Section 145
of the DGCL so require.

                  7.3.2.   In the event any Claim relating to Covered Events is
other than by or in the right of the Company, Indemnitee may, at the option of
Indemnitee, either control the defense thereof, require the Company to defend or
accept the defense provided under the D&O Insurance; provided, however, that
Indemnitee may not control the defense or require the Company to defend if such
decision would jeopardize the coverage provided by the D&O Insurance to the
Company or the other directors and officers covered thereby. In the event that
Indemnitee requires the Company to so defend, or in the event that Indemnitee
proceeds under the D&O Insurance but Indemnitee determines that such insurers
under the D&O Insurance are unable or unwilling to adequately defend Indemnitee
against any such Claim, the Company shall promptly undertake to defend any such
Claim, at the Company's sole cost and expense, utilizing counsel of Indemnitee's
choice who has been approved by the Company. If appropriate, the Company shall
have the right to participate in the defense of any such Claim.

                  7.3.3.   In the event the Company shall fail, as required by
any election by Indemnitee pursuant to Section 7.3.2, timely to defend
Indemnitee against any such Claim, Indemnitee shall have the right to do so,
including, without limitation, the right (notwithstanding

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Section 7.3.4) to make any settlement thereof, and to recover from the Company,
to the extent otherwise permitted by this Agreement, all Expenses and Losses
paid as a result thereof.

                  7.3.4.   The Company shall have no obligation under this
Agreement with respect to any amounts paid or to be paid in settlement of any
Claim without the express prior written consent of the Company to any related
settlement. In no event shall the Company authorize any settlement imposing any
liability or other obligations on Indemnitee without the express prior written
consent of Indemnitee. Neither the Company nor Indemnitee shall unreasonably
withhold consent to any proposed settlement.

         Section 8.        Determinations and Related Matters.

         8.1.     Presumptions.

                  8.1.1.   If a Change in Control shall have occurred,
Indemnitee shall be entitled to a rebuttable presumption that Indemnitee is
entitled to indemnification under this Agreement and the Company shall have the
burden of proof in rebutting such presumption.

                  8.1.2.   The termination of any Claim by settlement (whether
with or without court approval), or upon a plea of nolo contendere or its
equivalent, shall not, of itself, adversely affect either the right of
Indemnitee to indemnification under this Agreement, except as may be
specifically provided herein, or create a presumption that Indemnitee did not
meet or act in good faith and in a manner that Indemnitee reasonably believed to
be in or not opposed to the best interests of the Company or create a
presumption that (with respect to any criminal action or proceeding) Indemnitee
had reasonable cause to believe that Indemnitee's conduct was unlawful.

         8.2.     Appeals; Enforcement.

                  8.2.1.   In the event that (a) a Determination is made that
Indemnitee shall not be entitled to indemnification under this Agreement, (b)
any Determination to be made by Independent Legal Counsel is not made within 90
days of receipt by the Company of a request for indemnification pursuant to
Section 4.2.1 or (c) the Company fails to otherwise perform any of its
obligations under this Agreement (including, without limitation, its obligation
to make payments to Indemnitee following any Determination made or deemed to
have been made that such payments are appropriate), Indemnitee shall have the
right to commence a Claim in any court of competent jurisdiction, as
appropriate, to seek a Determination by the court, to challenge or appeal any
Determination which has been made, or to otherwise enforce this Agreement. If a
Change of Control shall have occurred, Indemnitee shall have the option to have
any such Claim conducted by a single arbitrator pursuant to the rules of the
American Arbitration Association. Any such judicial proceeding challenging or
appealing any Determination shall be deemed to be conducted de novo and without
prejudice by reason of any prior Determination to the effect that Indemnitee is
not entitled to indemnification under this Agreement. Any such Claim shall be at
the sole expense of Indemnitee except as provided in Section 9.2.

                  8.2.2.   If a Determination shall have been made or deemed to
have been made pursuant to this Agreement that Indemnitee is entitled to
indemnification, the Company shall be

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bound by such Determination in any judicial proceeding or arbitration commenced
pursuant to this Section 8.2, except if such indemnification is unlawful.

                  8.2.3.   The Company shall be precluded from asserting in any
judicial proceeding or arbitration commenced pursuant to this Section 8.2 that
the procedures and presumptions of this Agreement are not valid, binding and
enforceable and shall stipulate in any such court or before any such arbitrator
that the Company is bound by all the provisions of this Agreement. The Company
hereby consents to service of process and to appear in any judicial or
arbitration proceedings and shall not oppose Indemnitee's right to commence any
such proceedings.

         8.3.     Procedures. Indemnitee shall cooperate with the Company and
with any Person making any Determination with respect to any Claim for which a
claim for indemnification under this Agreement has been made, as the Company may
reasonably require. Indemnitee shall provide to the Company or the Person making
any Determination, upon reasonable advance request, any documentation or
information reasonably available to Indemnitee and necessary to (a) the Company
with respect to any such Claim or (b) the Person making any Determination with
respect thereto.

         Section 9.        Change in Control Procedures.

         9.1.     Determinations. If there is a Change in Control, any
Determination to be made under Section 4 shall be made by Independent Legal
Counsel selected by Indemnitee and approved by the Company (which approval shall
not be unreasonably withheld). The Company shall pay the reasonable fees of the
Independent Legal Counsel and indemnify fully such Independent Legal Counsel
against any and all expenses (including attorneys' fees), claims, liabilities
and damages arising out of or relating to this Agreement or the engagement of
Independent Legal Counsel pursuant hereto.





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<PAGE>


         9.2.     Expenses. Following any Change in Control, the Company shall
be liable for, and shall pay the Expenses paid or incurred by Indemnitee in
connection with the making of any Determination (irrespective of the
determination as to Indemnitee's entitlement to indemnification) or the
prosecution of any Claim pursuant to Section 8.2, and the Company hereby agrees
to indemnify and hold Indemnitee harmless therefrom. If requested by counsel for
Indemnitee, the Company shall promptly give such counsel an appropriate written
agreement with respect to the payment of its fees and expenses and such other
matters as may be reasonably requested by such counsel.

         Section 10.       Period of Limitations. No legal action shall be
brought and no cause of action shall be asserted by or in the right of the
Company, any Subsidiary, any Other Enterprise or any Affiliate of the Company
against Indemnitee or Indemnitee's spouse, heirs, executors, administrators or
personal or legal representatives after the expiration of two years from the
date of accrual of such cause of action, and any claim or cause of action of the
Company, any Subsidiary, any Other Enterprise or any Affiliate of the Company
shall be extinguished and deemed released unless asserted by the timely filing
of a legal action within such two-year period; provided, however, that if any
shorter period of limitations, whether established by statute or judicial
decision, is otherwise applicable to any such cause of action such shorter
period shall govern.

         Section 11.       Contribution. If the indemnification provisions of
this Agreement should be unenforceable under applicable law in whole or in part
or insufficient to hold Indemnitee harmless in respect of any Losses and
Expenses incurred by Indemnitee, then for purposes of this Section 11, the
Company shall be treated as if it were, or was threatened to be made, a party
defendant to the subject Claim and the Company shall contribute to the amounts
paid or payable by Indemnitee as a result of such Losses and Expenses incurred
by Indemnitee in such proportion as is appropriate to reflect the relative
benefits accruing to the Company on the one hand and Indemnitee on the other and
the relative fault of the Company on the one hand and Indemnitee on the other in
connection with such Claim, as well as any other relevant equitable
considerations. For purposes of this Section 11 the relative benefit of the
Company shall be deemed to be the benefits accruing to it and to all of its
directors, officers, employees and agents (other than Indemnitee) on the one
hand, as a group and treated as one entity, and the relative benefit of
Indemnitee shall be deemed to be an amount not greater than the Indemnitee's
yearly base salary or Indemnitee's compensation from the Company during the
first year in which the Covered Event forming the basis for the subject Claim
was alleged to have occurred. The relative fault shall be determined by
reference to, among other things, the fault of the Company and all of its
directors, officers, employees and agents (other than Indemnitee) on the one
hand, as a group and treated as one entity, and Indemnitee's and such group's
relative intent, knowledge, access to information and opportunity to have
altered or prevented the Covered Event forming the basis for the subject Claim.

                                       12
<PAGE>

         Section 12.       Miscellaneous Provisions.

         12.1.    Successors and Assigns, Etc.

                  12.1.1.  This Agreement shall be binding upon and inure to the
benefit of (a) the Company, its successors and assigns (including any direct or
indirect successor by merger, consolidation or operation of law or by transfer
of all or substantially all of its assets) and (b) Indemnitee and the heirs,
personal and legal representatives, executors, administrators or assigns of
Indemnitee.

                  12.1.2.  The Company shall not consummate any consolidation,
merger or other business combination, nor will it transfer 50% or more of its
assets (in one or a series of related transactions), unless the ultimate Parent
of the successor to the business or assets of the Company shall have first
executed an agreement, in form and substance satisfactory to Indemnitee, to
expressly assume all obligations of the Company under this Agreement and agree
to perform this Agreement in accordance with its terms, in the same manner and
to the same extent that the Company would be required to perform this Agreement
if no such transaction had taken place; provided that, if the Parent is not the
Company, the legality of payment of indemnity by the Parent shall be determined
by reference to the fact that such indemnity is to be paid by the Parent rather
than the Company.

         12.2.    Severability. The provisions of this Agreement are severable.
If any provision of this Agreement shall be held by any court of competent
jurisdiction to be invalid, void or unenforceable, such provision shall be
deemed to be modified to the minimum extent necessary to avoid a violation of
law and, as so modified, such provision and the remaining provisions shall
remain valid and enforceable in accordance with their terms to the fullest
extent permitted by law.

         12.3.    Rights Not Exclusive; Continuation of Right of
Indemnification. Nothing in this Agreement shall be deemed to diminish or
otherwise restrict Indemnitee's right to indemnification pursuant to any
provision of the Certificate of Incorporation or Bylaws of the Company, any
agreement, vote of stockholders or Disinterested Directors, applicable law or
otherwise. This Agreement shall be effective as of the date first above written
and continue in effect until no Claims relating to any Covered Event may be
asserted against Indemnitee and until any Claims commenced prior thereto are
finally terminated and resolved, regardless of whether Indemnitee continues to
serve as a director of the Company, any Subsidiary or any Other Enterprise.

         12.4.    No Employment Agreement. Nothing contained in this Agreement
shall be construed as giving Indemnitee any right to be retained in the employ
of the Company, any Subsidiary or any Other Enterprise.

         12.5.    Subsequent Amendment. No amendment, termination or repeal of
any provision of the Certificate of Incorporation or Bylaws of the Company, or
any respective successors thereto, or of any relevant provision of any
applicable law, shall affect or diminish in any way the rights of Indemnitee to
indemnification, or the obligations of the Company, arising under this

                                       13
<PAGE>

Agreement, whether the alleged actions or conduct of Indemnitee giving rise to
the necessity of such indemnification arose before or after any such amendment,
termination or repeal.

         12.6.    Notices. Notices required under this Agreement shall be given
in writing and shall be deemed given when delivered in person or sent by
certified or registered mail, return receipt requested, postage prepaid. Notices
shall be directed to the Company at GTx, Inc., 3 North Dunlap Street, Third
Floor, Van Vleet Building, Memphis, Tennessee 38163, Attention: Chief Executive
Officer, and to Indemnitee at the address set forth on the signature page hereto
(or such other address as either party may designate in writing to the other).

         12.7.    Governing Law. This Agreement shall be governed by and
construed and enforced in accordance with the laws of the State of Delaware
applicable to contracts made and performed in such state without giving effect
to the principles of conflict of laws.

         12.8.    Headings. The headings of the Sections of this Agreement are
inserted for convenience only and shall not be deemed to discriminate part of
this Agreement or to affect the construction thereof.

         12.9.    Counterparts. This Agreement may be executed in any number of
counterparts all of which taken together shall constitute one instrument.

         12.10.   Modification and Waiver. No supplement, modification or
amendment of this Agreement shall be binding unless executed in writing by both
of the parties hereto. No waiver of any of the provisions of this Agreement
shall constitute, or be deemed to constitute, a waiver of any other provisions
hereof (whether or not similar) nor shall any such waiver constitute a
continuing waiver.

                            [Signature page follows.]

                                       14
<PAGE>

         The parties hereto have caused this Agreement to be duly executed as of
the day and year first above written.

                                                  GTx, INC.

                                                  By:___________________________
                                                  Title:________________________

                                                  INDEMNITEE

                                                  ______________________________
                                                  Name:

                                                  Address: _____________________

                                                           _____________________

                                                           _____________________


[The Company is a party to an Indemnification Agreement in the form of this
Exhibit 10.12 with each of J.R. Hyde, III, Mitchell S. Steiner, Marc S.
Hanover, Mark E. Mosteller, Henry P. Doggrell, John H. Pontius and Rosemary
Mazanet.]


                                       15
<PAGE>

                                    Exhibit 1

                          Description of D&O Insurance

                                       A-1