On April 10, 2023 Aptose Biosciences Inc. ("Aptose" or the "Company") (NASDAQ: APTO, TSX: APS), a clinical-stage precision oncology company developing highly differentiated oral targeted agents to treat hematologic malignancies, reported financial results for the three months ended June 30, 2023, and provided a corporate update (Press release, Aptose Biosciences, AUG 10, 2023, View Source [SID1234634179]).

Schedule your 30 min Free 1stOncology Demo!
Discover why more than 1,500 members use 1stOncology™ to excel in:

Early/Late Stage Pipeline Development - Target Scouting - Clinical Biomarkers - Indication Selection & Expansion - BD&L Contacts - Conference Reports - Combinatorial Drug Settings - Companion Diagnostics - Drug Repositioning - First-in-class Analysis - Competitive Analysis - Deals & Licensing

                  Schedule Your 30 min Free Demo!

"While still early in our APTIVATE dose expansion trial with tuspetinib in combination with venetoclax (TUS/VEN), we are encouraged by what we’re seeing in very difficult to treat AML populations," said William G. Rice, Ph.D., Chairman, President and Chief Executive Officer. "Of particular importance are the tolerability of the TUS/VEN doublet and the breadth of responses in deep relapsed or refractory (R/R) AML patients who failed prior therapy with venetoclax (4 of 9 evaluable with Prior-VEN), among which responses were achieved in patients with wildtype FLT3 (2 of 3 evaluable with FLT3-WT) and one of whom harbored a TP53 mutation. Given the paucity of treatment options in this subpopulation that failed prior venetoclax therapy, we’re excited to build off of these positive results at future medical meetings later this year and leverage the TUS/VEN doublet data as a springboard to future triplet therapy in the front line setting."

"We are delighted to strengthen our relationship with Hanmi Pharmaceutical, which we believe reflects their recognition of the growing value of tuspetinib as a unique treatment for AML and possibly MDS, of the significant progress that Aptose has made with tuspetinib’s clinical development, and of the experienced and thoughtful nature of our team," said Dr. Rice. "We thank the Hanmi team, and in particular, Ms. Juhyun Lim, President of Hanmi Pharmaceutical, for her leadership and commitment to Aptose."

Key Corporate Highlights

Tuspetinib APTIVATE Expansion Trial – In the APTIVATE Phase 1/2 clinical trial of tuspetinib, a once daily oral agent with a unique kinase targeting pattern being developed for the treatment of patients with R/R AML, the tuspetinib and venetoclax (TUS/VEN) doublet combination treatment arm has demonstrated early responses (composite Complete Response rate (CRc) includes any CR, CRh, CRi and CRp to date) among efficacy evaluable R/R patients who previously failed venetoclax treatment. Among fifteen (15) patients dosed with TUS/VEN as of August 1, 2023, ten (10) patients have reached an efficacy evaluable stage. Among the ten evaluable patients, five (5) patients have achieved responses (50% CRc). Nine (9) of the ten (10) evaluable patients had failed prior venetoclax treatment, with four (4) of the nine (9) achieving responses (44% CRc). Three (3) responses emerged among seven (7) patients with wildtype FLT3 (43% CRc), which accounts for approximately 70% of the AML population, yet there are few treatment options and little in development for the wildtype patient population. The TUS/VEN combination continues to be well tolerated.

Aptose has a growing network of U.S. and international clinical sites recruiting a large spectrum of the R/R AML population, and the APTIVATE trial is focused on the rapid enrollment of patients to the TUS/VEN doublet.

Equity Investments in Aptose – Today, Aptose announced that it has entered into a binding term sheet with Hanmi Pharmaceutical, Inc. ("Hanmi Pharmaceutical") of Seoul, South Korea, for an investment of up to $7 million or 19.99 percent ownership interest in Aptose, in two tranches. The investment will provide additional financing for Aptose’s lead hematology drug, tuspetinib, formerly HM43239, which was licensed from Hanmi Pharmaceutical in November 2021 and is currently in the APTIVATE international phase 1/2 expansion trial in which patients with relapsed or refractory (R/R) acute myeloid leukemia (AML) receive tuspetinib monotherapy or in combination with venetoclax. The Company anticipates that the first tranche for $3 million will close by the end of August, subject to the satisfaction of customary closing conditions. The second tranche for up to $4 million or a maximum of 19.99 percent ownership interest will be triggered upon Aptose achieving certain manufacturing and data milestones related to tuspetinib, to be described in greater detail in definitive documentation and anticipated to be achieved by year-end.

The investment is conditional upon the Company receiving the conditional approval of the Toronto Stock Exchange (the "TSX") to list the Common Shares on the TSX. Listing will be subject to satisfying all of the requirements of the TSX. The investment is also subject to the requirements of the Nasdaq Capital Market.

During the quarter, Aptose also entered into a $25 million committed equity facility with Keystone Capital that provides Aptose the right to issue and sell up to $25 million of its common shares over the course of 24 months to the investor, subject to certain conditions being met, and subject to certain limitations and conditions imposed by Nasdaq, SEC and other regulators.

Completed Successful Type B EOP1 Meeting with US FDA – In June, Aptose held an End of Phase 1 (EOP1) Meeting with the FDA, where all tuspetinib data was reviewed. A monotherapy recommended Phase 2 dose of 80 mg daily was selected and all tuspetinib development paths remain open, including the single arm accelerated path.
Expected Milestones

European School of Haematology (ESH) Meeting – Plan to present expanded tuspetinib clinical data set (October 2023)

65th American Society of Hematology (ASH) (Free ASH Whitepaper) Annual Meeting & Exposition – Plan to present more mature clinical data set with tuspetinib (December 2023)

Plan to discuss strategies for potential future monotherapy accelerated development, doublet phase 2 development, and triplet pilot development (4Q 2023)

Research and development expenses increased by $3.2 million to $10.6 million for the three-month period ended June 30, 2023, as compared to $7.3 million for the comparative period in 2022. Changes to the components of our research and development expenses presented in the table above are primarily as a result of the following events:

Program costs for tuspetinib were $8.1 million for the three-month period ended June 30, 2023. The higher program costs for Tuspetinib in the current period represent the enrollment of patients in our APTIVATE clinical trial, our healthy volunteer trial, manufacturing activities to support clinical development, and related expenses.
Program costs for luxeptinib decreased by approximately $1.7 million, primarily due to lower clinical trial costs and lower manufacturing costs as a result of the current formulation requiring less API than the prior formulation.
Program costs for APTO-253 decreased by approximately $169 thousand, due to the Company’s decision on December 20, 2021 to discontinue further clinical development of APTO-253.
Personnel-related expenses decreased by $354 thousand, related to fewer employees in the current three-month period, partially offset by salary increases.
Stock-based compensation decreased by approximately $266 thousand in the three months ended June 30, 2023, compared to the three months ended June 30, 2022, primarily due to stock options granted with lower grant date fair values, in the current period.
Research and development expenses increased by $4.7 million to $19.4 million for the six-month period ended June 30, 2023, as compared to $14.7 million for the comparative period in 2022. Changes to the components of our research and development expenses presented in the table above are primarily as a result of the following events:

Program costs for tuspetinib were $12.8 million for the six-month period ended June 30, 2023, an increase of $9.3 million compared with $3.5 million in the corresponding period in 2022. The higher program costs for Tuspetinib in the current period represent the enrollment of patients in our APTIVATE clinical trial, our healthy volunteer trial, clinical study supplies, and related expenses.
Program costs for luxeptinib decreased by approximately $3.2 million from $5.2 million in the six months ended June 30, 2022 to $2.0 million in the current period, primarily due to lower clinical trial costs and lower manufacturing costs as a result of the current formulation requiring less API than the prior formulation.
Program costs for APTO-253 decreased by approximately $253 thousand, due to the Company’s decision on December 20, 2021 to discontinue further clinical development of APTO-253.
Personnel-related expenses decreased by $610 thousand, related to fewer employees in the current six-month period and partially offset by salary increases.
Stock-based compensation decreased by approximately $559 thousand in the six months ended June 30, 2023, compared to the three months ended June 30, 2022, primarily due to stock options granted with lower grant date fair values, in the current period.

Conference Call & Webcast:

Date: Thursday, August 10, 2023
Time:
5:00 PM ET
Audio Webcast Only: link
Q&A Participant Registration Link*: link (https://register.vevent.com/register/BI29f5f8f4655b45cf8b92fd8f79f69f8f)

*Analysts interested in participating in the question-and-answer session will pre-register for the event from the participant registration link above to receive the dial-in numbers and a unique PIN, which are required to access the conference call. They also will have the option to take advantage of a Call Me button and the system will automatically dial out to connect to the Q&A session.

The audio webcast also can be accessed through a link on the Investor Relations section of Aptose’s website here. A replay of the webcast will be available on the Company’s website for 30 days.

The press release, the financial statements and the management’s discussion and analysis for the quarter ended June 30, 2023 will be available on SEDAR+ at www.sedarplus.ca and EDGAR at www.sec.gov/edgar.shtml.