Aptose Biosciences : Corporate Presentation January 2021

Aptose Corporate Presentation

J A N UA R Y 2 0 2 1

P R E C I S I O N O N C O L O G Y F O R

T H E R A P I E S O F T O M O R R O W

NASDAQ: APTO TSX: APS

Disclosure

This presentation does not, and is not intended to, constitute or form part of, and should not be construed as, an offer or invitation for the sale or purchase of, or a solicitation of an offer to purchase, subscribe for or otherwise acquire, any securities, businesses and/or assets of any entity, nor shall it or any part of it be relied upon in connection with or act as any inducement to enter into any contract or commitment or investment decision whatsoever.

This presentation contains forward-looking statements, which reflect APTOSE Biosciences Inc.'s (the "Company") current expectations, estimates and projections regarding

future events, including statements relating to our business strategy, our clinical development plans, our ability to obtain the substantial capital we require, our plans to secure strategic partnerships and to build our pipeline, our clinical trials and their projected timeline, the efficacy and toxicity of our product candidates, potential new intellectual property, our plans, objectives, expectations and intentions; and other statements including words such as "anticipate", "contemplate", "continue", "believe", "plan", "estimate", "expect", "intend", "will", "should", "may", and other similar expressions. Such statements constitute forward-looking statements within the meaning of securities laws.

Although the Company believes that the views reflected in these forward-looking statements are reasonable, such statements involve significant risks and uncertainties, and undue reliance should not be placed on such statements. Certain material factors or assumptions are applied in making these forward-looking statements, and actual results may differ materially from those statements. Those factors and risks include, but are not limited to, our ability to raise the funds necessary to continue our operations, changing market conditions, the successful and timely completion of our clinical studies including delays, the demonstration of safety and efficacy of our drug candidates, our ability to recruit patients, the establishment and maintenance of corporate alliances, the market potential of our product candidates, the impact of competitive products and pricing, new product development, changes in laws and regulations, uncertainties related to the regulatory approval process and other risks detailed from time to time in the Company's ongoing quarterly filings and annual reports.

Forward-looking statements contained in this document represent views only as of the date hereof and are presented for the purpose of assisting potential investors

in understanding the Company's business, and may not be appropriate for other purposes. The Company does not undertake to update any forward-looking statements, whether written or oral, that may be made from time to time by or on its behalf, except as required under applicable securities legislation. Investors should read

the Company's continuous disclosure documents available at www.sedar.comand EDGAR at www.sec.gov/edgar.shtml, especially the risk factors detailed therein.

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Aptose Highlights

APTOSE

CG-806

Oral FLT3 / BTK

Kinase Inhibitor

FDA Orphan Drug Designation in AML

APTO-253

MYC Inhibitor

FDA Orphan Drug Designation in AML

Serving the Needs

of Patients

Clinical stage biotech company developing 1st-in-class, small molecule, targeted medicines Precision treatment of hematologic malignancies; life-threatening / orphan diseases Multiple assets addressing multiple cancers indications for optionality and value creation

Precision to suppress multiple validated cancer targets, yet spares safety targets Inhibits all forms of BTK → Phase 1a/b trial ongoing with CLL & NHL patients Inhibits all forms of FLT3 → Phase 1a/b trial ongoing with AML patients Potential for the treatment of a broad range of hematologic malignancies

Only clinical stage agent known to directly target G-Quadruplexof notable MYC oncogene Phase 1b trial ongoing for AML & MDS demonstrating safety and MYC inhibition

Seek to demonstrate near-termclinical POC with AML and CLL

Seek to deliver new agents that serve broadly the needs of patients with CLL and AML Seek to deliver agents that avoid the rapid emergence of drug resistance

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CG-806

1 s t- i n - Class Oral Kinase Inhibitor

M u t a t i o n	A g n o s t i c	F LT 3 I n h i b i t o r
M u t a t i o n	A g n o s t i c	r B T K I n h i b i t o r

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