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EXCEL - IDEA: XBRL DOCUMENT - Oncternal Therapeutics, Inc.Financial_Report.xls
EX-4.9 - EX-4.9 - Oncternal Therapeutics, Inc.a2223461zex-4_9.htm
EX-10.39 - EX-10.39 - Oncternal Therapeutics, Inc.a2223461zex-10_39.htm
EX-32.2 - EX-32.2 - Oncternal Therapeutics, Inc.a2223461zex-32_2.htm
EX-10.25 - EX-10.25 - Oncternal Therapeutics, Inc.a2223461zex-10_25.htm
EX-23.1 - EX-23.1 - Oncternal Therapeutics, Inc.a2223461zex-23_1.htm
EX-10.35 - EX-10.35 - Oncternal Therapeutics, Inc.a2223461zex-10_35.htm
EX-31.2 - EX-31.2 - Oncternal Therapeutics, Inc.a2223461zex-31_2.htm
EX-31.1 - EX-31.1 - Oncternal Therapeutics, Inc.a2223461zex-31_1.htm
EX-10.29 - EX-10.29 - Oncternal Therapeutics, Inc.a2223461zex-10_29.htm
10-K - 10-K - Oncternal Therapeutics, Inc.a2223461z10-k.htm
EX-10.34 - EX-10.34 - Oncternal Therapeutics, Inc.a2223461zex-10_34.htm

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EXHIBIT 32.1

CERTIFICATION PURSUANT TO
18 U. S. C. SECTION 1350,
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

        In connection with the Annual Report of GTx, Inc. (the "Company") on Form 10-K for the year ended December 31, 2014, as filed with the Securities and Exchange Commission on the date hereof (the "Report"), I, Marc S. Hanover, Chief Executive Officer of the Company certify, pursuant to Rule 13a-14(b) or Rule 15d-14(b) and 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that:

    1.
    The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

    2.
    The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

Date: March 16, 2015    

/s/ Marc S. Hanover

Marc S. Hanover
Chief Executive Officer

 

 

        This certification accompanies the Form 10-K to which it relates, is not deemed filed with the Securities and Exchange Commission and is not to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934 (whether made before or after the date of the Form 10-K), irrespective of any general incorporation language contained in such filing.




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CERTIFICATION PURSUANT TO 18 U. S. C. SECTION 1350, AS ADOPTED PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002