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EXHIBIT 31.4

PRINCIPAL FINANCIAL OFFICER CERTIFICATION

I, Jason T. Shackelford, certify that:

1.

I have reviewed this Amendment No. 1 to the Annual Report on Form 10-K/A of GTx, Inc.; and

2.

Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report.

Date: April 30, 2019

/s/ Jason T. Shackelford
Jason T. Shackelford
Vice President, Finance and Accounting and
Principal Financial and Accounting Officer

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EXHIBIT 31.4

PRINCIPAL FINANCIAL OFFICER CERTIFICATION