Every 8-K that APTOSE BIOSCIENCES INC (APTOF) has filed with the SEC in the last 24 months is listed below, newest first, and each one links through to the document itself with the summary and the scores our analysis gives it.
A 8-K covers material events a company has to report between its quarterly reports, so if you follow APTOF and want that one kind of document rather than the whole filing history, this is the page to keep. The company's other filings, of every form, are on the full APTOF filings page.
Aptose Biosciences Inc. has been acquired by Hanmi Pharmaceutical through a statutory plan of arrangement, and is becoming a wholly owned subsidiary of the Hanmi Purchasers. HS North America Ltd. bought all Aptose common shares not already owned by Hanmi for C$2.41 in cash per share, for approximately 2,043,719 shares.
The aggregate consideration paid to these shareholders was about USD$3,466,470 (C$4,925,362.79). Hanmi previously held 508,710 shares, or 19.93% of the 2,552,429 shares outstanding immediately before closing. The C$2.41 price represents a 28% premium to Aptose’s 30‑day VWAP of C$1.88 on the TSX before signing the arrangement agreement.
Aptose’s shares are expected to be delisted from the TSX on or about July 3, 2026, and the company plans to file Form 15 to terminate or suspend its U.S. reporting obligations, effectively ending its status as a public reporting issuer in Canada and the United States.
Aptose Biosciences Inc. has completed its previously announced plan of arrangement under which HS North America Ltd., a wholly owned subsidiary of Hanmi Pharmaceutical, acquired all Aptose common shares not already owned by Hanmi and its affiliates.
Shareholders other than the Hanmi purchasers and their affiliates will receive C$2.41 in cash per share, a 28% premium to Aptose’s 30-day VWAP of C$1.88 on the TSX before the arrangement agreement. The transaction received shareholder and final court approval on March 31, 2026 and necessary regulatory approvals in Korea. Aptose’s common shares are expected to be delisted from the TSX on or about July 3, 2026, and the company has applied to cease being a reporting issuer in Canada and to terminate its public reporting obligations in both Canada and the United States.
Aptose Biosciences furnished a press release detailing updated clinical data from its Phase 1/2 TUSCANY study of tuspetinib (TUS) in combination with venetoclax and azacitidine (TUS+VEN+AZA) as frontline therapy for newly diagnosed acute myeloid leukemia (AML) patients ineligible for induction chemotherapy.
The triplet was given to 32 patients (29 evaluable), with an overall composite complete response rate of 86.2% and minimal residual disease (MRD) negativity of 86.2% among those achieving CR/CRh. The MRD-negative rate among all patients dosed was 62.5%.
At the 160 mg TUS dose level (13 patients), the composite complete response rate was 76.9%, including complete remissions in all four patients with TP53-mutated complex karyotype. The regimen was reported as well tolerated, with no treatment-related deaths and no treatment-related QTc prolongation, CPK elevation, or differentiation syndrome.
Aptose Biosciences provided an update on its planned acquisition by Hanmi Pharmaceutical. Closing of the previously announced plan of arrangement has been further delayed because certain Korean regulatory approvals are still in progress, although the parties do not anticipate this review will prevent completion and now target closing in June. On financing, Aptose received an additional advance of US$2.0 million under a US$11.9 million loan facility from Hanmi, bringing total advances to US$9.9 million and expects the final US$2.0 million shortly. Upon completion of the arrangement, Hanmi is to acquire all Aptose common shares it does not already own for C$2.41 per share in cash, a 28% premium to the C$1.88 30‑day VWAP previously disclosed. The company notes these funds support uninterrupted conduct of the TUSCANY clinical trial of tuspetinib in newly diagnosed AML.
Aptose Biosciences Inc. reported a first quarter 2026 net loss of $7.6 million, wider than the $5.5 million loss a year earlier, as operating expenses rose to $7.2 million. Cash and restricted cash were $4.1 million, while shareholders’ deficit reached $34.7 million and working capital was negative.
The company states it does not have sufficient cash to fund operations and is relying on advances from Hanmi Pharmaceutical while undertaking cost reductions. Aptose is the target of an expected acquisition by Hanmi, under which shareholders will receive C$2.41 per share, a 28% premium to the 30-day VWAP at signing, with closing delayed pending Korean regulatory approvals.
Clinically, Aptose highlighted progress in its TUSCANY trial of tuspetinib in combination with venetoclax and azacitidine for newly diagnosed AML, including an upcoming oral presentation at EHA 2026, and it returned license rights to luxeptinib (CG-806) to CGI.
Aptose Biosciences Inc. announced that closing of its previously disclosed plan of arrangement with Hanmi Pharmaceutical has been delayed because certain Korean regulatory approvals are still in progress. The parties state they do not anticipate the review will prevent closing.
Aptose and Hanmi now target completing the arrangement in May. Upon completion, Hanmi will acquire all Aptose common shares not already owned or controlled by Hanmi and its affiliates, and remaining Aptose shareholders are expected to receive C$2.41 in cash per share, a 28% premium to the 30‑day VWAP of C$1.88.
Aptose Biosciences Inc. reported that shareholders approved a plan of arrangement under which a Hanmi Pharmaceutical subsidiary will acquire all Aptose common shares not already owned by Hanmi for C$2.41 in cash per share, a 28% premium to the 30‑day VWAP of C$1.88. The company also received a final court order from the Court of King’s Bench of Alberta approving the transaction, with closing expected by the end of April 2026, subject to remaining conditions.
Clinically, the TUSCANY study of the TUS+VEN+AZA triplet in newly diagnosed AML showed high-quality responses, with CR/CRh rates of 90% across 40–120 mg TUS doses, 100% at 80 mg and 120 mg, and 78% MRD‑negative remissions among responders, alongside a favorable safety profile.
Financially, for 2025 Aptose recorded a net loss of $25.5 million, similar to 2024, on reduced research and development expenses of $11.3 million versus $15.1 million a year earlier. Year-end 2025 cash and equivalents were $4.1 million, with working capital of $(2.9) million and shareholders’ deficit of $(27.2) million, and operations have been funded by more than US$41 million of Hanmi debt facilities.
Aptose Biosciences Inc. reported the results of a special shareholder meeting held on March 31, 2026. Shareholders approved a continuance of the corporation from the Canada Business Corporations Act to the Business Corporations Act (Alberta), and also approved a plan of arrangement with Hanmi-related entities.
Under the approved arrangement, HS North America Ltd., a wholly owned subsidiary of Hanmi Pharmaceutical Co. Ltd., will acquire all Aptose common shares not already owned or controlled by the Hanmi entities or their affiliates. The continuance resolution received roughly 92.42% of votes cast in favor, while the arrangement resolution received about 84.87% support, indicating strong shareholder backing for both the corporate law change and the proposed acquisition structure.
Aptose Biosciences Inc. reported an amendment to the employment agreement of its Chairman, President and Chief Executive Officer, Dr. William Rice. The First Amendment to the Second Amended and Restated Employment Agreement, effective March 12, 2026, clarifies that no deferred compensation plan was ever created, no deferred compensation was earned, and no deferred compensation benefits are owed to Dr. Rice. It also confirms that Dr. Rice is solely responsible for any potential individual taxes, penalties and interest on all benefits paid or payable under his current and prior agreements. The full text of the First Amendment is included as an exhibit.
Aptose Biosciences Inc. reported that proxy advisor Glass Lewis has recommended shareholders vote “FOR” its proposed plan of arrangement with Hanmi Pharmaceutical. Under this arrangement, Hanmi and its subsidiary would acquire all Aptose common shares not already owned by them. Shareholders are being asked to approve both the Arrangement and a continuance of Aptose from the CBCA to the ABCA at a reconvened virtual special meeting on March 31, 2026. The proxy voting deadline is 11:00 a.m. (Eastern time) on March 27, 2026. Aptose’s Special Transaction Committee and Board unanimously recommend voting FOR the Continuance and the Arrangement, which remain subject to customary conditions, including Court approval and TSX approval.
Aptose Biosciences Inc. announced that proxy advisory firm ISS has recommended shareholders vote “FOR” a special resolution approving the previously disclosed plan of arrangement under which Hanmi Pharmaceutical and its subsidiary will acquire all Aptose common shares they do not already own.
Under the proposed transaction, Aptose shareholders other than the Hanmi buyers and their affiliates would receive C$2.41 in cash per share, described as a 28% premium to Aptose’s 30-day VWAP of C$1.88 on the TSX. ISS also recommended approval of a corporate continuance from the CBCA to the ABCA, which it viewed as having largely similar shareholder rights.
A special meeting to vote on the arrangement and continuance has been reconvened for March 31, 2026, with a proxy voting deadline of 11:00 a.m. Eastern time on March 27, 2026. Completion of the transaction remains subject to shareholder approval, court approval, TSX approval and other customary closing conditions.
Aptose Biosciences Inc. detailed changes to its planned acquisition by a subsidiary of Hanmi Pharmaceutical and an expanded funding arrangement to support its lead drug Tuspetinib. An amended and restated arrangement agreement keeps in place the plan for Hanmi’s HS North America Ltd. to acquire all Aptose common shares it does not already own by way of a statutory plan of arrangement under Alberta law, and reconvenes the special shareholder meeting for March 31, 2026. Aptose’s board unanimously recommends that shareholders vote in favor of the continuance and the Arrangement.
The company also entered into a US$11.1 million second amended and restated facility agreement with Hanmi, providing multiple interest-bearing advances at 6% per annum to fund business and clinical expenses tied to Tuspetinib in acute myeloid leukemia. Prior Hanmi facilities were treated as related-party transactions under Canadian rules, with Aptose’s board unanimously concluding, under a financial hardship exemption, that these financings improve the company’s financial position and are reasonable in the circumstances.
Aptose Biosciences Inc. filed a current report on Form 8-K to furnish information under Regulation FD. On December 19, 2025, the company issued a press release, which is attached as Exhibit 99.1 and incorporated by reference. The company specifies that, under General Instruction B.2, the press release is being furnished rather than filed, meaning it is not subject to certain liability provisions of the Exchange Act or automatically incorporated into other securities filings unless specifically referenced.
Aptose Biosciences Inc. filed a current report to furnish information under Regulation FD. The company states that on December 6, 2025, it issued a press release, which is attached as Exhibit 99.1 to this report and incorporated by reference.
The press release is being provided under Item 7.01 (Regulation FD Disclosure) and, consistent with the stated instructions, is treated as “furnished” rather than “filed” for purposes of the Exchange Act and the Securities Act, unless later specifically incorporated by reference.
Aptose Biosciences Inc. agreed to be acquired by Hanmi Pharmaceuticals through a court-approved plan of arrangement. Hanmi’s subsidiary will purchase all Aptose common shares it does not already own for C$2.41 in cash per share, a 28% premium to Aptose’s 30‑day VWAP of C$1.88 on the TSX. The deal requires Aptose to first continue under the Business Corporations Act (Alberta), then complete the arrangement.
Closing is subject to court approval and shareholder approvals, including at least two‑thirds of votes cast and a separate majority of minority shareholders under MI 61‑101. Aptose’s board, following a special committee’s unanimous recommendation and external advice, unanimously determined the transaction is in the company’s best interests. Directors and officers signed voting support agreements. After completion, Aptose expects its shares to be delisted from all exchanges and it will cease to be a reporting issuer. An expense fee of C$300,000 is payable to Hanmi’s subsidiary if the agreement is terminated in certain circumstances.
Aptose Biosciences Inc. filed a current report to furnish a company press release under Regulation FD. The filing states that a press release dated November 19, 2025 is attached as Exhibit 99.1 and is incorporated by reference, but is treated as “furnished” rather than “filed” for liability purposes.
Aptose Biosciences Inc. filed a Form 8-K to furnish a press release covering its results of operations and financial condition. The press release, dated November 13, 2025, is attached as Exhibit 99.1 and is incorporated by reference for informational purposes.
The company states that the Exhibit 99.1 information is being furnished under the Exchange Act and will not be deemed filed under Section 18, nor automatically incorporated into Securities Act or Exchange Act filings unless specifically referenced.
Aptose Biosciences Inc. furnished a press release under Item 7.01 (Regulation FD) via a Form 8-K. The release is attached as Exhibit 99.1 and incorporated by reference in this report.
Consistent with General Instruction B.2, the Item 7.01 information is deemed furnished, not filed, and is not incorporated by reference into Securities Act or Exchange Act filings unless expressly stated by specific reference.
Aptose Biosciences Inc. filed a current report to furnish a press release issued on October 16, 2025. The company is using this filing to make the press release publicly available under Regulation FD, which is intended to provide fair disclosure of information to all investors at the same time. The press release itself is attached as Exhibit 99.1 and is incorporated by reference only as specifically indicated in future filings.
Aptose Biosciences Inc. filed a current report to furnish information under Regulation FD. On September 22, 2025, the company issued a press release, which is attached to the report as Exhibit 99.1 and incorporated by reference. The company notes that this press release is being furnished under Item 7.01 of the Exchange Act and is not deemed “filed” for liability purposes under Section 18 or automatically incorporated into other securities law filings.