PART I—FINANCIAL INFORMATION

Item 1. Financial Statements

Compass Therapeutics, Inc. and Subsidiaries

Condensed Consolidated Balance Sheets

(In thousands, except par value)

The accompanying notes are an integral part of these unaudited condensed consolidated financial statements.

Compass Therapeutics, Inc. and Subsidiaries

Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited)

(In thousands, except per share data)

The accompanying notes are an integral part of these unaudited condensed consolidated financial statements.

Compass Therapeutics, Inc. and Subsidiaries

Condensed Consolidated Statements of Stockholders’ Equity (Unaudited)

(In thousands)

The accompanying notes are an integral part of these unaudited condensed consolidated financial statements.

Compass Therapeutics, Inc. and Subsidiaries

Condensed Consolidated Statements of Cash Flows (Unaudited)

(In thousands)

The accompanying notes are an integral part of these unaudited condensed consolidated financial statements.

Compass Therapeutics, Inc. and Subsidiaries

Notes to Unaudited Condensed Consolidated Financial Statements

Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

The following discussion of the financial condition and results of operations of Compass Therapeutics, Inc. should be read in conjunction with the financial statements and the notes to those statements included in this Quarterly Report on Form 10-Q for the three and nine month periods ended September 30, 2023. Some of the information contained in this discussion and analysis, including information with respect to our plans and strategy for our business, includes forward-looking statements that involve risk, uncertainties and assumptions. You should read the “Risk Factors” section of this Quarterly Report on Form 10-Q and the “Risk Factors” section included in our Annual Report on Form 10-K for the fiscal year ended December 31, 2022, for a discussion of important factors that could cause actual results to differ materially from the results described in or implied by the forward-looking statements contained in the following discussion and analysis.

Overview

We are a clinical-stage, oncology-focused biopharmaceutical company developing proprietary antibody-based therapeutics to treat multiple human diseases. Our scientific focus is on the relationship between angiogenesis, the immune system, and tumor growth. Our pipeline of novel product candidates is designed to target multiple critical biological pathways required for an effective anti-tumor response. These include modulation of the microvasculature via angiogenesis-targeted agents, induction of a potent immune response via activators on effector cells in the tumor microenvironment, and alleviation of immunosuppressive mechanisms used by tumors to evade immune surveillance. We plan to advance our product candidates through clinical development as both standalone therapies and in combination with proprietary pipeline antibodies based on supportive clinical and nonclinical data.

In January 2023, we redirected our internal research activities from early-stage discovery to translational research and preclinical development support. Our research group is now focused on further and more detailed characterization of our three product candidates, development of additional assays to facilitate regulatory filings, assessment of combinations of our product candidates with other drugs, assessment of additional indications for our product candidates and various pre-clinical studies further expanding our understanding of mechanisms of action, synergistic activities and optimal combinations of the product candidates. We believe that these activities will allow us to focus our resources on our three product candidate programs, unlock the therapeutic potential of these programs and combinations thereof, and subsequently enhance the return on investment for our shareholders.

We currently have two product candidates in the clinical stage of development: CTX-009 and CTX-471. In addition, the IND to our third product candidate, CTX-8371, has been cleared in October, and is expected to enter the clinic in the fourth quarter of 2023. A summary of these product candidates is presented below. For a more detailed description, see our Annual Report on Form 10-K for the fiscal year ended December 31, 2022.

CTX-009(a.k.a. ABL001) - anti-DLL4 x VEGF-A bispecific antibody

CTX-009 is an investigational bispecific antibody that is designed to simultaneously block DLL4 and VEGF-A signaling pathways, which are critical to angiogenesis and tumor vascularization. Preclinical and early clinical data of CTX-009 as a monotherapy and in combination with chemotherapy suggest that blockade of both pathways provides robust anti-tumor activity across several solid tumors, including colorectal, gastric, cholangiocarcinoma, pancreatic and non-small cell lung cancer.

CTX-009 is undergoing clinical development in patients with advanced solid tumors in the United States, South Korea and China. A Phase 1 dose escalation and dose expansion monotherapy trial in patients with solid tumors and a Phase 1b trial of CTX-009 in combination with chemotherapy was completed in South Korea. In addition, a Phase 2 trial of CTX-009 in combination with chemotherapy in patients with advanced biliary tract cancer is ongoing in South Korea. The first part of the Phase 2 trial is complete and data from that study were presented at ASCO GI in January 2023.

We currently have two open clinical trials in the United States: a Phase 2 trial of CTX-009 in patients with advanced colorectal cancer (“CRC”) and a Phase 2/3 trial of CTX-009 in combination with paclitaxel in patients with advanced biliary tract cancer (“BTC”).

We licensed the exclusive global rights to CTX-009, outside of South Korea, from ABL Bio, Inc. (“ABL Bio”), a South Korea-based clinical-stage company focused on developing antibody therapeutics. South Korean rights are held by Handok Pharmaceuticals, Inc. (“Handok”) and China rights were out-licensed from the Company to Elpiscience Biopharmaceuticals Co., Limited (“Elpiscience”).

Our strategy is to develop CTX-009 in all of the indications in which patients have a need for effective and novel therapeutic agents and data supports the potential therapeutic benefit of CTX-009. We chose BTC and CRC as our lead indications based on a number of factors, including CTX-009 activity observed in the Phase 1, 1b and 2 clinical trials, lack of effective therapies for these patient populations in the targeted lines of therapy and the potential for a straight-forward regulatory route to approval.

We submitted an Investigational New Drug (“IND”) application to the U.S. Food and Drug Administration (the “FDA”) in December 2021 for CTX-009 and the FDA cleared our IND application in January 2022. All of our CTX-009 trials are being conducted in the United States under this IND.

We are conducting a Phase 2 monotherapy clinical trial of CTX-009 in patients with metastatic colorectal cancer who have received two or three prior systemic therapies irrespective of their KRAS mutation status. The trial is designed to assess the safety and efficacy of CTX-009 as a monotherapy in patients with colorectal cancer treated in the third and fourth-line settings and utilizes a Simon Two-Stage adaptive design where the criteria to advance to the second stage of the trial is three partial responses observed in 37 patients enrolled in Part A of the trial. Based on the Simon Two-Stage design, when the criteria for the first stage are met, the trial progresses to the second stage, at which time 47 additional patients will be enrolled. We expect the first interim data readout from the trial in the fourth quarter of 2023. The trial can be found on www.clinicaltrials.gov (identifier NCT 05513742).

In addition, we are conducting a randomized Phase 2/3 trial for CTX-009 in combination with paclitaxel in adult patients with unresectable, advanced, metastatic or recurrent biliary tract cancers (“BTC” or “cholangiocarcinoma”) who have received one prior systemic chemotherapy regimen. The trial is designed to assess the safety and efficacy of the combination of CTX-009 and paclitaxel versus paclitaxel alone in patients treated in the second-line settings. The trial is designed to enroll 150 patients, who will be randomized in a 2:1 ratio to receive CTX-009 plus paclitaxel (n=100) or paclitaxel alone (n=50). The primary endpoint of the trial is overall response rate (“ORR”) and the secondary endpoints include progression free survival (“PFS”), disease control rate (“DCR”), duration of response (“DOR”) and overall survival (“OS”).

In the first nine months of this year, we opened 29 clinical sites and started enrolling patients in this study.  Enrollment in the third quarter increased relative to the first half of the year, in part due to the opening of several clinical sites at large medical centers across the country that have high enrollment rate relative to the smaller medical centers. Top line data from this study is expected in the second half of 2024. The trial can be found on www.clinicaltrials.gov (Identifier NCT 05506943).

We intend to explore the potential of CTX-009 in additional indications, based on data from pre-clinical models, potential biomarkers such as DLL4, and clinical data from CTX-009 trials providing signs of potential activity of CTX-009 in additional indications such as ovarian cancer, liver cancer, gastric cancer, pancreatic cancer, renal cell cancer, neuroendocrine cancer and others.

In addition, we are developing a plan to study the combination of CTX-009 with our novel bispecific checkpoint blocker, CTX-8371, and with other checkpoint blockers, such as pembrolizumab and atezolizumab. Additionally, we are considering the combination of CTX-009 with our novel CD137 agonistic antibody, CTX-471, which is currently in a Phase 1b clinical trial in patients with advanced solid tumors.

CTX-471 - a monoclonal antibody agonist of CD137

CTX-471, our monoclonal antibody product candidate, is a fully human, IgG4 monoclonal antibody that is an agonist of CD137, a key co-stimulatory receptor on immune cells. Binding of CTX-471 to CD137 has been observed to lead to ligand-stimulated activation of T-cells and NK cells. In treated mice, dosing with CTX-471 led to extensive reprogramming of the tumor microenvironment, including increased recruitment of immune cells, reversion of exhausted cytotoxic CD8+ T-cells, reductions in immunosuppressive regulatory T-cells and reductions in immunosuppressive tumor-associated macrophages. Long after the completion of the treatment with CTX-471, a period described as eight half-lives of the antibody, treated mice exhibited immune memory that prevented re-establishment of the same tumor.

The CD137 antigenic site recognized by CTX-471 does not block the binding of CD137 ligand and is differentiated from the site recognized by CD137 antibodies from competitors. We designed the antibody using different backbones and chose to use a human IgG4 backbone for CTX-471 to enable engagement of Fc receptors FcgRI and FcgRIIb to facilitate CD137 cross-linking while avoiding binding to FcgRIIIa and depletion of immune effector cells through ADCC.

Immune cell depletion experiments showed that the activity of CTX-471 required the presence of CD4+ T-cells, CD8+ T-cells, and NK cells, indicating a coordinated involvement of both innate and adaptive immune cells. Encouragingly, treatment of tumors in mice with CTX-471 led to a marked reprogramming of the immune component of the tumor microenvironment. We also observed that tumors treated with CTX-471 had an approximate two-fold reduction in the number of immunosuppressive tumor-associated macrophages.

In addition, we have observed potent activity in other syngeneic tumor models including tumor eradication in the A20 model of lymphoma, the MC38 model of colon carcinoma and in the EMT6 model of breast cancer.

We believe that the ability of CTX-471 to transform the tumor microenvironment through the combined action of immune cell recruitment, alleviation of T-cell exhaustion, suppression of Tregs, and reduction of tumor suppressing macrophages leads to CTX-471’s antitumor activity in mouse models.

In October 2022, we announced a clinical collaboration with Merck & Co. (“Merck”, known as MSD outside the United States and Canada) to evaluate CTX-471 in combination with KEYTRUDA® (pembrolizumab). Compass is the study sponsor and Merck provides the clinical supply of KEYTRUDA®. Additionally, we formed a joint development committee (“JDC”) with Merck to review the results of this clinical trial.

In November 2022, we announced the first patient was dosed in the combination arm of the Phase 1 trial. This combination arm is enrolling patients with metastatic or locally advanced non-small cell lung cancer, melanoma, small cell lung cancer, mesothelioma and head and neck cancer that have progressed after treatment with a PD-1 or PD-L1 checkpoint inhibitor. Patients enrolled in the trial will be treated with CTX-471 in combination with pembrolizumab with the goal of restoring response.

In the third quarter of 2023, the dose escalation portion of the study was completed with no dose limiting toxicities (“DLTs”) observed. We are currently planning for cohort expansion which we expect to begin in the first quarter of 2024.

CTX-8371 - a bispecific antibody that simultaneously targets both PD-1 and PD-L1

CTX-8371 is a bispecific antibody that binds to both PD-1 and PD-L1, the targets of well-known and widely used checkpoint inhibitor antibodies and in addition acts via differentiated mechanism-of-action that involves cleavage of cell surface PD-1. Preclinical studies demonstrate that CTX-8371 has the ability to outperform PD-1, PD-L1, and combinations of the two to activate T-cells in in vitro assays. In mouse xenografts, treatment with CTX-8371 led to significantly greater tumor growth control and longer survival than treatment with a PD-1 inhibitor alone, a PD-L1 inhibitor alone or the combination of PD-1 and PD-L1 inhibitors.

IND-enabling studies on CTX-8371, including GLP toxicology studies in non-human primates were completed in the first quarter of 2023. An IND was submitted CTX-8371 to the FDA in the third quarter of 2023. This IND was accepted and cleared by the FDA in October 2023 and we plan on initiating a clinical trial in the fourth quarter of 2023.

OPERATING ACTIVITIES

We have funded our operations primarily with proceeds from the sale of our equity securities. Through September 30, 2023, we have received $412 million in gross proceeds from the sale of equity securities. 

We have incurred significant operating losses since inception and have not generated any revenue from the sale of products and we do not expect to generate any revenue from the sale of products in the near future, if at all. Our ability to generate product revenue sufficient to achieve profitability will depend heavily on the successful development and eventual commercialization of our treatments and any future product candidates. Our net losses were $10.0 million and $12.0 million for the three months ended September 30, 2023 and 2022, respectively. Our net losses were $29.1 million and $27.6 million for the nine months ended September 30, 2023 and 2022, respectively. We had an accumulated deficit of $301.9 million on September 30, 2023. We expect to continue to incur significant expenses for at least the next several years as we advance through clinical development, develop additional product candidates and seek regulatory approval of any product candidates that complete clinical development. In addition, if we obtain marketing approval for any product candidates, we expect to incur significant commercialization expenses related to product manufacturing, marketing, sales and distribution. We may also incur expenses in connection with the in-licensing or acquisition of additional product candidates.

Until such time as we can generate significant revenue from product sales, if ever, we expect to finance our operations through equity and debt financings, or other capital sources, which may include collaborations with other companies or other strategic transactions. As of September 30, 2023, we had $164 million in cash, cash equivalents and marketable securities. We expect that such cash resources will enable us to fund our operating expenses and capital expenditure requirements into 2026. 

Because of the numerous risks and uncertainties associated with product development, we are unable to predict the timing or amount of increased expenses or when, or if, we will be able to achieve or maintain profitability. Even if we are able to generate product sales, we may not become profitable. If we fail to become profitable or are unable to sustain profitability on a continuing basis, then we may be unable to continue our operations at planned levels and be forced to reduce or terminate our operations. Our financial statements do not include any adjustments that might result from the outcome of this uncertainty.

Components of Results of Operations

Research and Development

Research and development expenses consist primarily of costs incurred in connection with the development of our product candidates, CTX-471, CTX-8371 and CTX-009. We expense research and development costs as incurred. These expenses include:

Advance payments that we make for goods or services to be received in the future for use in research and development activities are recorded as prepaid expenses. Such amounts are recognized as an expense as the goods are delivered or the related services are performed, or until it is no longer expected that the goods will be delivered or the services rendered.

Product candidates in later stages of clinical development generally have higher development costs than those in earlier stages of clinical development, primarily due to the increased size and duration of later-stage clinical trials. We expect that our research and development expenses will increase substantially in connection with our planned clinical development activities in the future. At this time, we cannot accurately estimate or know the nature, timing and costs of the efforts that will be necessary to complete the clinical development of any future product candidates.

The successful development and commercialization of product candidates is highly uncertain. This is due to the numerous risks and uncertainties associated with product development and commercialization.

General and Administrative Expenses

General and administrative expenses consist primarily of salaries and related costs for personnel in executive, finance, business development and administrative functions. General and administrative expenses also include legal fees relating to patent and corporate matters, professional fees for accounting, auditing, tax, insurance, administrative travel expenses and other operating costs.

We anticipate that our general and administrative expenses will increase in the future as we increase our headcount to support our business operations.

Other Income

Other income consists of interest income on marketable securities.

Results of Operations

Comparison of the Three months ended September 30, 2023 and 2022

The following table summarizes our results of operations for the three months ended September 30, 2023 and 2022 (in thousands):

Research and Development Expenses

Research and development expenses decreased by $1.0 million, or 10%, for the three months ended September 30, 2023 compared to the three months ended September 30, 2022. The decrease primarily came from $1.1 million spent in 2022 for toxicological studies related to CTX-8371, which were not incurred in 2023. We spent $0.3 million more on CTX-009 primarily for manufacturing and clinical costs, and $0.6 million less for the other two programs (CTX-471 and CTX-8371) for the three months ended September 30, 2023 as compared to the same period in 2022.   

We track outsourced development, personnel costs and other research and development costs of specific programs. Research and development expenses are summarized by program in the table below (in thousands):

General and Administrative Expenses

General and administrative expenses increased by $0.3 million or 10% for the three months ended September 30, 2023 as compared to the same period in 2022, which is from additional stock compensation expense.      

Other income

For the three months ended September 30, 2023 and 2022, other income consists primarily of interest income.

Income Tax Expense

During the three months ended September 30, 2023 and 2022, we recognized no income tax expense.   

Comparison of the Nine Months Ended September 30, 2023 and 2022

The following table summarizes our results of operations for the nine months ended September 30, 2023 and 2022 (in thousands):

Research and Development Expenses

Research and development expenses increased by $5.6 million, or 28%, for the nine months ended September 30, 2023 compared to the nine months ended September 30, 2022. The increase primarily came from an increase in clinical costs of $3.8 million and personnel costs of $1.3 million.  We spent $9.6 million more on CTX-009 primarily for manufacturing and clinical costs, and $2.8 million less for the other two programs (CTX-471 and CTX-8371) for the nine months ended September 30, 2023 as compared to the same period in 2022.

We track outsourced development, personnel costs and other research and development costs of specific programs. Research and development expenses are summarized by program in the table below (in thousands):

General and Administrative Expenses

General and administrative expenses increased by $0.6 million, or 7%, to $9.3 million for the nine months ended September 30, 2023, as compared to the same period in 2022, which is from additional stock compensation expense.    

Other income

For the nine months ended September 30, 2023 and 2022, other income consists primarily of interest income.

Income Tax Expense

During the nine months ended September 30, 2023 and 2022, we recognized no income tax expense.

Liquidity and Capital Resources

Since our inception, we have devoted substantially all of our efforts to organizing and staffing our Company, business planning, raising capital, research and development activities, building our intellectual property portfolio and providing general and administrative support for these operations. We have funded our operations primarily with proceeds from the sale of our equity securities. Through September 30, 2023, we have received $412 million in gross proceeds from the sale of equity securities. As of September 30, 2023, we had cash, cash equivalents and marketable securities of $164 million. 

Through September 30, 2023, we sold through our at-the-market (“ATM”) agreement with Jefferies LLC, 951,873 shares of common stock at an average price of $3.28 for total proceeds of $3.1 million and net proceeds of $3.0 million.

Funding Requirements

Our primary use of cash is to fund operating expenses, primarily research and development expenditures. Cash used to fund operating expenses is impacted by the timing of when we pay these expenses, as reflected in the change in our outstanding accounts payable, accrued expenses and prepaid expenses. Because of the numerous risks and uncertainties associated with research, development and commercialization of pharmaceutical products, we are unable to estimate the exact amount of our operating capital requirements. Our future funding requirements will depend on many factors, including, but not limited to:

Until such time, if ever, as we can generate substantial product revenue, we expect to finance our operations through a combination of equity offerings, debt financings, collaborations, strategic alliances and marketing, distribution or licensing arrangements. To the extent that we raise additional capital through the sale of equity or convertible debt securities, current stockholders’ interest will be diluted, and the terms of these securities may include liquidation or other preferences that adversely affect rights of common stockholders. Debt financing and preferred equity financing, if available, may involve agreements that include covenants limiting or restricting our ability to take specific actions, such as incurring additional debt, making acquisitions or capital expenditures or declaring dividends. If we raise additional funds through collaborations, strategic alliances or marketing, distribution or licensing arrangements with third parties, we may have to relinquish valuable rights to our technologies, future revenue streams, research programs or product candidates, or grant licenses on terms that may not be favorable to us. If we are unable to raise additional funds through equity or debt financings or other arrangements when needed, we may be required to delay, limit, reduce or terminate our research, product development or future commercialization efforts, or grant rights to develop and market product candidates that we would otherwise prefer to develop and market ourselves.

Cash Flows

The following table shows a summary of our cash flows for the periods indicated (in thousands):

Operating Activities

During the nine months ended September 30, 2023, we used $28.3 million of cash in operating activities, resulting from our net loss of $29.1 million plus the change in operating assets and liabilities of $2.7 million, partially offset by non-cash charges of $3.5 million.

During the nine months ended September 30, 2022, we used $23.5 million of cash in operating activities, resulting from our net loss of $27.6 million plus the change in operating assets and liabilities of $1.3 million, partially offset by non-cash charges of $5.4 million.

Investing Activities

During the nine months ended September 30, 2023, $20.7 million of cash was provided by investing activities, primarily related to the net sale of marketable securities. During the nine months ended September 30, 2022, we used $104.6 million of cash in investing activities which primarily related to the net purchase of marketable securities.

Financing Activities

During the nine months ended September 30, 2023, $3.1 million of cash was provided by financing activities. This primarily included $3.0 million of net cash from sale of common stock under an ATM Agreement, after issuance costs. We had $5 thousand of financing activities during the nine months ended September 30, 2022 resulting from the exercise of stock options.

Future Funding Requirements

We expect our expenses to increase substantially in connection with our ongoing activities. The timing and amount of our operating expenditures will depend largely on:

We believe that our existing cash, cash equivalents and marketable securities as of filing of the Form 10-Q will enable us to fund our operating expenses and capital expenditure requirements into 2026 based on our current plans, which may change based on clinical or pre-clinical results. These plans include: A Phase 2/3 and two Phase 2 clinical trials of CTX-009, a Phase 1b combination trial for CTX-471 and a Phase 1 trial of CTX-8371.  We expect that we will require additional funding to complete the clinical development of these three programs, commercialize our product candidates, if we receive regulatory approval, and pursue in-licenses or acquisitions of other product candidates. If we receive regulatory approval for CTX-009, CTX-471 or CTX-8371 or other product candidates, we expect to incur significant commercialization expenses related to product manufacturing, sales, marketing and distribution, depending on where we choose to commercialize these product candidates ourselves.

Until such time, if ever, as we can generate substantial product revenue, we expect to finance our cash needs through a combination of equity and debt financings, collaborations, strategic alliances, and marketing, distribution or licensing arrangements with third parties. To the extent that we raise additional capital through the sale of equity or convertible debt securities, ownership interest may be materially diluted, and the terms of such securities could include liquidation or other preferences that adversely affect your rights as a common stockholder. Debt financing and preferred equity financing, if available, may involve agreements that include restrictive covenants that limit our ability to take specified actions, such as incurring additional debt, making capital expenditures or declaring dividends. If we raise funds through collaborations, strategic alliances or marketing, distribution or licensing arrangements with third parties, we may have to relinquish valuable rights to our technologies, future revenue streams, research programs or product candidates or grant licenses on terms that may not be favorable to us. If we are unable to raise additional funds through equity or debt financings or other arrangements when needed, we may be required to delay, reduce or eliminate our product development or future commercialization efforts, or grant rights to develop and market product candidates that we would otherwise prefer to develop and market ourselves.

Item 3. Quantitative and Qualitative Disclosures About Market Risk.

Not applicable since we are a smaller reporting company.

Item 4. Controls and Procedures.

Management’s Evaluation of Our Disclosure Controls and Procedures

Our management, with the participation of our Chief Executive Officer and Chief Operating Officer (Principal Financial Officer), evaluated the effectiveness of our disclosure controls and procedures, as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, as amended, or the Exchange Act, as of September 30, 2023. Management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving their objectives and management necessarily applies its judgment in evaluating the cost-benefit relationship of possible controls and procedures. Based on the evaluation of our disclosure controls and procedures as of September 30, 2023, our Chief Executive Officer and Chief Operating Officer (Principal Financial Officer) concluded that, as of such date, our disclosure controls and procedures were effective.

Changes in Internal Control over Financial Reporting

There was no change in our internal control over financial reporting, as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act, that occurred during the quarter ended September 30, 2023 that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting.

PART II—OTHER INFORMATION

Item 1. Legal Proceedings.

As of the date of this Quarterly Report on Form 10-Q, we are not involved in any material legal proceedings. However, from time to time, we could be subject to various legal proceedings and claims that arise in the ordinary course of our business activities. Regardless of the outcome, legal proceedings can have an adverse impact on us because of defense and settlement costs, diversion of management resources and other factors.

Item 1A. Risk Factors

In addition to the other information set forth in this report, you should carefully consider the risk factors discussed in Part I, Item 1A “Risk Factors” in our Annual Report on Form 10-K for the fiscal year ended December 31, 2022, which could materially affect our business, financial condition, or results of operations.

Item 2. Unregistered Sales of Equity Securities and Use of Proceeds.

None. 

Item 3. Defaults Upon Senior Securities.

None.

Item 4. Mine Safety Disclosures.

Not applicable.

Item 5. Other Information.

The following disclosure is provided pursuant to Item 5.02 (Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers) of Form 8-K:

On November 08, 2023, the board of directors of Compass Therapeutics, Inc. (the “Company”) approved a plan of succession with respect to Thomas J. Schuetz, M.D., Ph.D., the Company’s current Chief Executive Officer, and Vered Bisker-Leib, Ph.D., M.B.A., the Company’s President and Chief Operating Officer. Under this succession plan, effective as of January 9, 2024, Dr. Bisker-Leib has agreed to succeed Dr. Schuetz as Chief Executive Officer, while Dr. Schuetz has agreed to transition to the role of President of Research and Development. In connection with this succession plan, the Company has entered transition agreements with each individual, pursuant to which, among other things, Dr. Schuetz has also agreed to be appointed as Vice Chair of the Company’s board of directors, and Dr. Bisker-Leib has agreed to join the Company’s board of directors, in each case effective as of January 9, 2024. In addition, the Company intends to negotiate new or amended employment agreements for each individual, to take effect from and after January 9, 2024, in such individual’s new role. Information required by Items 401(b), (d), (e) and Item 404(a) of Regulation S-K with respect to Dr. Bisker-Leib and Dr. Schuetz is included in the Company’s Annual Report on Form 10-K filed on March 15, 2023, and incorporated herein by reference, as applicable.

Item 6. Exhibits.