Ms. Susan Pietropaolo reports

APTOSE ANNOUNCES PRICING OF $8.4 MILLION PUBLIC OFFERING AND A CONCURRENT $4 MILLION PRIVATE PLACEMENT WITH HANMI PHARMACEUTICAL

Aptose Biosciences Inc. has priced an underwritten public offering of 4,912,280 common shares of the company at a public offering price of $1.71 (U.S.) per share. Each common share will also include a warrant to purchase a common share at a price of $1.71 per warrant share. Gross proceeds from the public offering, before deducting underwriting discounts and commissions and offering expenses payable by Aptose, are expected to be approximately $8.4-million (U.S.). The underwriters have been granted a 30-day option to purchase up to an additional 736,842 common shares and/or 736,842 warrants in the public offering, under the same terms and conditions.

Aptose also announced the pricing of a concurrent $4-million private placement of common shares with Hanmi Pharmaceutical Inc., Seoul, South Korea, representing ownership of 19.97 per cent of the outstanding common shares of the company following the private placement. Under the terms of the strategic investment, Hanmi will purchase each common share at a price of $1.90, representing an 11-per-cent premium over the price of the common shares issued in the public offering. The company will also issue Hanmi warrants to purchase common shares at a price of $1.71 per warrant share. Upon the closing of the private placement, Hanmi will have satisfied its remaining investment obligations under the existing subscription agreement and investor rights agreement (announced Sept. 6, 2023) between Aptose and Hanmi.

The public offering is expected to close on or about Jan. 30, 2024, subject to satisfaction of customary closing conditions. The private placement is expected to close on or about Jan. 31, 2024, subject to satisfaction of customary closing conditions.

Aptose intends to use the net proceeds of the public offering and private placement to (i) support clinical trials for tuspetinib; (ii) support manufacture of tuspetinib clinical supplies; and (iii) for working capital and general corporate purposes.

Newbridge Securities Corp. is acting as the sole bookrunning manager for the public offering and as placement agent for the private placement.

No common shares, prefinanced warrants or warrants will be offered or sold in Canada as part of the public offering or private placement. The public offering and private placement are subject to the approval of the Toronto Stock Exchange and Nasdaq. For the purposes of TSX approval, the company is relying on the exemption set forth in Section 602.1 of the TSX company manual, which provides that the TSX will not apply its standards to certain transactions involving eligible interlisted issuers on a recognized exchange, such as Nasdaq.

The securities to be sold in the public offering are being offered by Aptose pursuant to a registration statement on Form S-1 (file No. 333-275870), including a base prospectus, that was previously filed by Aptose with the Securities and Exchange Commission (SEC) and was declared effective on Jan. 25, 2024. The public offering is being made only by means of a written prospectus and prospectus supplement that form a part of the registration statement. Before you invest, you should read the prospectus supplement and the accompanying prospectus and other documents the company has filed with the SEC for more complete information about the company and the public offering. You may get these documents for free by visiting EDGAR on the SEC website. Alternatively, copies of the final prospectus supplement may be obtained, once available, by contacting Newbridge Securities Corp.

About Aptose Biosciences Inc.

Aptose Biosciences is a clinical-stage biotechnology company developing precision medicines addressing unmet medical needs in oncology, with an initial focus on hematology. The company's small molecule cancer therapeutics pipeline includes products designed to provide single agent efficacy and to enhance the efficacy of other anti-cancer therapies and regimens without overlapping toxicities.

We seek Safe Harbor.