Welcome to our dedicated page for Aptose Bioscienc SEC filings (Ticker: APTOF), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
The Aptose Biosciences Inc. (APTOF) SEC filings page on Stock Titan provides access to the company’s regulatory disclosures as a Canadian issuer reporting to the U.S. Securities and Exchange Commission. Aptose files current reports on Form 8-K under Commission File Number 001-32001, alongside its Canadian securities filings. These documents are central for investors who want to understand the company’s clinical-stage oncology business, financial condition, and pending corporate transactions.
For Aptose, Form 8-K filings are particularly important. Recent 8-Ks include Regulation FD disclosures that furnish press releases about tuspetinib (TUS) clinical data from the TUSCANY Phase 1/2 trial, including safety, complete remission (CR/CRh) rates, and minimal residual disease (MRD) findings in acute myeloid leukemia (AML). Other 8-Ks report quarterly financial results, detailing research and development expenses by program, general and administrative costs, cash balances, and the company’s reliance on loan facilities from Hanmi Pharmaceutical Co. Ltd. to fund operations.
Another critical category of filings relates to material definitive agreements and corporate transactions. Aptose has filed an 8-K describing its definitive arrangement agreement with Hanmi and HS North America Ltd., under which a Hanmi subsidiary will acquire all Aptose common shares not already owned or controlled by Hanmi or its affiliates, subject to shareholder and court approvals. That filing outlines the transaction structure, consideration for minority shareholders, required approvals, and the expectation that, after completion, Aptose will no longer be subject to certain reporting requirements and its shares will be delisted from stock exchanges including the TSX.
Through Stock Titan, investors can review these filings and use AI-powered summaries to interpret key sections, such as risk factor discussions, forward-looking statements, and the implications of financing and transaction agreements. The platform also tracks new 8-Ks in real time, helping users monitor Aptose’s ongoing clinical disclosures, financial updates, and progress toward the proposed acquisition.
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 another quarter of operating losses and remains under significant financial strain. For the three months ended March 31, 2026, the company generated no revenue and recorded a net loss of $7.6 million, widening from $5.5 million a year earlier, or $2.99 per share.
At March 31, 2026, total assets were $10.7 million against total liabilities of $45.4 million, leaving a shareholders’ deficit of $34.7 million. Cash and restricted cash totaled only $4.1 million, and current liabilities exceeded current assets by about $5.1 million, prompting explicit disclosure of substantial doubt about the company’s ability to continue as a going concern.
Aptose is heavily reliant on related-party financing from Hanmi. A loan payable to Hanmi and related facilities totaled $32.9 million plus $1.3 million of accrued interest, with additional advances received after quarter-end under a second amended facility of up to $11.1 million. In parallel, Aptose has agreed to a plan of arrangement under which a Hanmi subsidiary will acquire all remaining common shares for C$2.41 per share, canceling all incentive securities and warrants. Shareholders approved the transaction on March 31, 2026, and closing is expected in May 2026, subject to customary conditions and Korean regulatory approvals.
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., a clinical-stage oncology biotech focused on hematologic cancers, has agreed to be acquired by Hanmi Pharmaceutical via a Canadian plan of arrangement. Hanmi’s subsidiary will purchase all Aptose common shares it does not already control for C$2.41 in cash per share, with all options, RSUs and warrants cancelled at closing and the shares delisted from the Toronto Stock Exchange.
Shareholders approved the transaction on March 31, 2026, and the outside closing date was extended to June 30, 2026, but completion still depends on regulatory and court approvals and the absence of legal restraints. The company warns that if the deal fails, its business, financial results and share price could be adversely affected and it may need to consider insolvency.
Aptose’s lead asset, tuspetinib, is an oral kinase inhibitor being developed mainly in frontline triple therapy with venetoclax and azacitidine for newly diagnosed acute myeloid leukemia. Across early Phase 1/2 studies, the TUS+VEN+AZA triplet has shown high composite complete remission and minimal residual disease–negative response rates in genetically diverse, often hard‑to‑treat AML patients, with a consistently favorable safety profile.
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.