Form 8-K
0001738021 False 0001738021 2022-05-04 2022-05-04 iso4217:USD xbrli:shares iso4217:USD xbrli:shares



Washington, D.C. 20549





Pursuant to Section 13 or 15(d)
of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported):  May 4, 2022


Compass Therapeutics, Inc.

(Exact name of registrant as specified in its charter)


(State or Other Jurisdiction of Incorporation)(Commission File Number)(I.R.S. Employer Identification No.)

80 Guest Street, Suite 601

Boston, Massachusetts 02135

(Address of Principal Executive Offices) (Zip Code)

(617) 500-8099

(Registrant's telephone number, including area code)


(Former name or former address, if changed since last report)


Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s)Name of each exchange on which registered
Common Stock, $0.0001 par value per shareCMPXNASDAQ Capital Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.

Item 7.01. Regulation FD Disclosure.

On May 4, 2022, Compass Therapeutics, Inc. (the “Company”) issued a press release announcing positive interim data for its ongoing Phase 2 clinical trial assessing its clinical program, CTX-009, in combination with paclitaxel in advanced biliary tract cancers. A copy of the press release is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

Also on May 4, 2022, the Company hosted a conference call to discuss the foregoing interim Phase 2 data. A copy of the slide presentation used during the Company’s conference call is attached hereto as Exhibit 99.2 and is incorporated herein by reference.

The information in this Item 7.01 (including Exhibit 99.1 and Exhibit 99.2) shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as expressly set forth by specific reference in such a filing.

Item 9.01. Financial Statements and Exhibits.


Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

 Compass Therapeutics, Inc.
Date: May 4, 2022By: /s/ NEIL LERNER        
  Neil Lerner
  VP of Finance




Compass Therapeutics Reports Positive Interim Phase 2 Data of CTX-009 in Combination with Paclitaxel in Biliary Tract Cancers

CTX-009 Demonstrated a 42% Overall Response Rate (ORR) Based on 10 Partial Responses (PRs) in 24 Enrolled Patients

CTX-009 Continues to be Well Tolerated, Consistent with the Phase 1 Studies

Compass Plans to Initiate Stage 2 of the Phase 2 Study in the U.S. in Q3 2022

Compass to Host Key Opinion Leader Webinar on May 4, 2022 at 8:00 a.m. ET

BOSTON, May 04, 2022 (GLOBE NEWSWIRE) -- Compass Therapeutics, Inc. (Nasdaq: CMPX), a clinical-stage, oncology-focused biopharmaceutical company developing proprietary antibody-based therapeutics to treat multiple human diseases, today reported additional interim results from a Phase 2 study of CTX-009 in combination with paclitaxel in patients with biliary tract cancers (BTC). The data show that:

Thomas Schuetz, M.D., Ph.D., Chief Executive Officer, and Scientific Founder of Compass, said “We are excited by these impressive interim Phase 2 results and believe CTX-009 is a promising investigational drug. In the initial data review of this trial, reported in November 2021, CTX-009 exhibited a 29% ORR and a 100% CBR. We are very encouraged by the performance of CTX-009 across a larger patient population, particularly the maturing of the dataset, with the ORR moving from 29% in 17 evaluable patients to 42% in all 24 patients enrolled.”

Dr. Schuetz continued, “The findings reported today suggest that CTX-009, if approved, may represent a novel therapeutic option for patients with BTC who have limited treatment choices and poor prognoses. We are very pleased to see the strategy of blocking both DLL4 and VEGF-A in a bispecific antibody continue to yield positive data.”

Vered Bisker-Leib, Ph.D., President and Chief Operating Officer of Compass said “CTX-009 demonstrated responses across all of the four BTC subtypes enrolled in the trial and good overall tolerability. These are very encouraging aspects of the Phase 2 results and mark an important step forward in the ongoing development of CTX-009 as a potential new treatment for patients with BTC. We look forward to studying CTX-009 further in Phase 2 trials, which we expect to begin in the U.S. in the third quarter.”

CTX-009 Phase 2 Study Overview

The Phase 2 study has a Simon Two-Stage adaptive design where three PRs among the first 21 patients enrolled in the first stage of the study will advance the study to the second stage. In November 2021, Compass reported that there were five PRs observed among the first 17 evaluable patients, and therefore, the criteria to advance the study to its second stage was met. The study is currently being conducted at four leading medical centers in Korea. In the United States, an IND was opened in January of 2022 and first patient dose is projected to take place in early Q3 2022.


All patients enrolled in the study had BTC, classified into four subgroups: intrahepatic cholangiocarcinoma (37.5%), extrahepatic cholangiocarcinoma (12.5%), gallbladder cancer (29.2%) and ampullary cancer (20.8%).

As of the data cut-off date April 14, 2022, 24 patients were enrolled and dosed with at least one cycle of CTX-009 and paclitaxel, and 22 were evaluable for response. All patients enrolled in the study have advanced BTC; 45.8% of the patients received one prior therapy and 54.2% of the patients received at least two prior therapies. Almost all patients (95.8%) received gemcitabine/cisplatin.

Patients had a median age of 61.5 years, an ECOG performance status of 0 (54.2%) or 1 (45.8%).

Preliminary Activity Data

CTX-009 exhibited a 42% ORR based on 10 patients with PRs, including nine confirmed PRs by RECIST 1.1 and one PR pending confirmation.

Two patients were not evaluable for the purpose of efficacy, and 22 of the 24 patients have had stable disease or better observed leading to a CBR of 92%. As of the cutoff date, seven patients were continuing to receive treatment, including five patients who had been on treatment for over nine months.

Preliminary Safety Data

CTX-009, in combination with paclitaxel, continues to be well tolerated, consistent with the Phase 1 studies, with hypertension and neutropenia being the most common events related to CTX-009 and paclitaxel, respectively.

Of the 24 subjects enrolled in the study, all subjects had at least one AE related to CTX-009 and/or paclitaxel. The most common adverse events (all Grades) occurring in at least three patients were anemia (12.5%), asthenia (25.0%), fatigue (16.7%), edema (16.7%), pyrexia (16.7%), neutropenia (54.2%), thrombocytopenia (20.8%), headache (16.7%), proteinuria (20.8%), dysphonia (12.5%), dyspnea (25%), epistaxis (33.3%), pulmonary hypertension (16.7%, all Grade 1) and hypertension (50.0%).

Grade 3 or greater treatment-emergent adverse events (TEAE) occurring in more than one patient include neutropenia (n=12; 50.0%), hypertension (n=4; 16.7%), anemia (n=3; 12.5%) and thrombocytopenia (n=2; 8.3%); all TEAEs were manageable with standard treatment.

About the Trial

The Phase 2 trial was designed as a prospective, multi-center, open-label, Simon Two-Stage adaptive design trial to evaluate the use of CTX-009 in combination with paclitaxel for the treatment of patients with BTC. The study enrolled patients with advanced, unresectable, metastatic or recurrent biliary tract cancer with an ECOG performance status of 0 or 1.

The initial phase of the trial was conducted in Korea and enrolled 24 subjects at four leading medical centers. All subjects received bi-weekly doses of 10 mg/kg of CTX-009, and paclitaxel, dosed at 80 mg/m2 weekly every three out of four weeks.

The primary endpoint for the study is ORR, based on the proportion of subjects whose best overall response is assessed to be Complete Response (CR) or Partial Response (PR) per Independent Radiology review. Secondary outcome measures include assessments of several standard measures of disease progression.

About CTX-009

CTX-009 is a bispecific antibody that simultaneously blocks Delta-like ligand 4/Notch (DLL4) and vascular endothelial growth factor A (VEGF-A) signaling pathways, which are critical to angiogenesis and tumor vascularization. Preclinical and early clinical data of CTX-009 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. Partial responses to CTX-009 as a monotherapy have been observed in heavily pre-treated cancer patients who were resistant to currently approved anti-VEGF therapies. CTX-009 has completed a Phase 1 monotherapy dose escalation and dose expansion study and a Phase 2 combination study is ongoing. Initiation of a Phase 2 trial in the U.S. is planned for Q3 2022.

Compass holds the global rights to CTX-009 (also known as ABL001) with the exception of rights in Korea, held by Handok, Inc. ( and rights in China, which Compass out-licensed to Elpiscience Biopharma, Ltd. (

About Biliary Tract Cancers

Biliary tract cancers (BTC) are a group of rare and aggressive gastrointestinal (GI) cancers that form in the cells of the bile ducts (cholangiocarcinoma), gallbladder or ampulla of Vater (where the bile duct and pancreatic duct connect to the small intestine).

In the United States approximately 18,300 cases of BTC are diagnosed annually,1 including cholangiocarcinoma, gallbladder and ampullary subtypes. Only 10% of these patients present at an early stage when they would be candidates for surgical resection. The vast majority present with locally advanced or metastatic BTC, for which there are very few therapeutic options.2



About Compass Therapeutics

Compass Therapeutics, Inc. is a clinical-stage oncology-focused biopharmaceutical company developing proprietary antibody-based therapeutics to treat multiple human diseases. Compass’s scientific focus is on the relationship between angiogenesis, the immune system, and tumor growth. The company’s pipeline of novel product candidates was 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. Compass plans to advance its product candidates through clinical development as both standalone therapies and in combination with proprietary pipeline antibodies and selected targeted therapies based on supportive clinical and nonclinical data. The company was founded in 2014 and is headquartered in Boston, Massachusetts. The Company’s website is

Webinar Information

Compass will host a webcast on Wednesday, May 4th at 8:00 a.m. ET

Registration for the webcast or access to a replay of the call is available by clicking here.

Forward-Looking Statements

This press release contains forward-looking statements. Statements in this press release that are not purely historical are forward-looking statements. Such forward-looking statements include, among other things, references to Compass’s product candidate, CTX-009, its development, regulatory plans with respect thereto and therapeutic potential thereof. Actual results could differ from those projected in any forward-looking statements due to numerous factors. Such factors include, among others, Compass’s ability to raise the additional funding it will need to continue to pursue our business and product development plans, the inherent uncertainties associated with developing product candidates and operating as a development stage company, Compass’s ability to identify additional product candidates for development, Compass’s ability to develop, complete clinical trials for, obtain approvals for and commercialize any of its product candidates, competition in the industry in which Compass operates and market conditions. These forward-looking statements are made as of the date of this press release, and Compass assumes no obligation to update the forward-looking statements, or to update the reasons why actual results could differ from those projected in the forward-looking statements, except as required by law. Investors should consult all the information set forth herein and should also refer to the risk factor disclosure set forth in the reports and other documents Compass files with the SEC available at

Media Contact
Anna Gifford, Communications Manager

Investor Relations Contact
Joyce Allaire
LifeSci Advisors 


Exhibit 99.2


DO NOT DISTRIBUTE WITHOUT PERMISSION | © 2022 Compass Therapeutics Presentation May 4, 2022



DISCLAIMER This presentation has been prepared by Compass Therapeutics, Inc. ("we," "us," "our," or the “Company”). Statements contained herein are made as of the date of this presentation unless stated otherwise, and this presentation shall not under any circumstances create an implication that the information contained herein is correct as of any time after such date or that information will be updated or revised to reflect information that subsequently becomes available or changes occurring after the date hereof. This presentation includes forward - looking statements regarding our drug candidates, the timing of the start and conclusion of ongoing or planned clinical trials, including the potential impact of the ongoing COVID - 19 pandemic on our business, the timing and outcome of regulatory decisions, future availability of clinical trial data, our collaborations for our product candidates and the maintenance of those collaborations, business and results from operations, and other matters. Actual results could differ materially from those contained in any forward - looking statements as a result of various factors, including without limitation: that our drug candidates do not advance in development or result in approved products on a timely or cost effective basis or at all; the cost, timing and results of clinical trials; our ability to manage and mitigate the impact of the ongoing COVID - 19 pandemic; that many drug candidates that have completed early - stage trials do not become approved drugs on a timely or cost effective basis or at all; the ability to enroll patients in clinical trials; possible safety and efficacy concerns; regulatory developments; our ability to protect our intellectual property rights, and unexpected costs, charges or expenses that reduce cash runway. Our pipeline programs are in various stages of pre - clinical and clinical development, and the process by which such pre - clinical or clinical therapeutic candidates could potentially lead to an approved therapeutic is long and subject to significant risks and uncertainties. These and other risks and uncertainties that we face are described in our most recent Annual Report on Form 10 - K, and in other filings that we make with the Securities and Exchange Commission from time to time. We undertake no obligation to update forward - looking statements as a result of new information or otherwise. This presentation also contains estimates and other statistical data made by independent parties and by us relating to market size and growth and other data about our industry. This data involves a number of assumptions and limitations, and you are cautioned not to give undue weight to such estimates. In addition, projections, assumptions, and estimates of our future performance and the future performance of the markets in which we operate are necessarily subject to a high degree of uncertainty and risk. This presentation concerns drugs that are under clinical investigation, and which have not yet been approved for marketing by the U . S . Food and Drug Administration (FDA) . It is currently limited by Federal law to investigational use, and no representation is made as to its safety or effectiveness for the purposes for which it is being investigated . 2 DO NOT DISTRIBUTE WITHOUT PERMISSION | © 2022



Advanced Biliary Track Cancers (BTC) Richard M. Goldberg MD Professor and Director Emeritus The West Virginia University Cancer Institute



Subtypes of BTC • Gallbladder cancer (GBCA), • Cholangiocarcinoma – intrahepatic [IHCC], – Perihilar [PCCA], – Extrahepatic [ECC] • Ampulla of Vater cancer (AVC)



BTC Epidemiology, 2021 US Worldwide Cases 18,300 210,887 Deaths 11,310 (62%) 173,974 (84%) • Lifetime risk: Highest in Chile and Asian countries • 76% Increase in incidence over last 2 decades • Risk factors: Inherited, liver flukes, chronic liver or biliary inflammation, obesity, tobacco use



Presentation • Jaundice, yellow eyes, itching, dark urine, light colored stool • Loss of appetite and weight loss • Abdominal pain • Night sweats • Found incidentally at the time of gall bladder surgery





Original Article Cisplatin plus Gemcitabine versus Gemcitabine for Biliary Tract Cancer Juan Valle, M.D., Harpreet Wasan, M.D., Daniel H. Palmer, M.D., Ph.D., David Cunningham, M.D., Alan Anthoney, M.D., Anthony Maraveyas, M.D., Ph.D., Srinivasan Madhusudan, M.D., Ph.D., Tim Iveson, M.D., Sharon Hughes, B.Sc., Stephen P. Pereira, M.D., Ph.D., Michael Roughton, M.Sc., John Bridgewater, M.D., Ph.D., for the ABC - 02 Trial Investigators N Engl J Med Volume 362(14):1273 - 1281 April 8, 2010



Patient Enrollment, Randomization, and Treatment Valle J et al. N Engl J Med 2010;362:1273 - 1281 • The ABC - 02 Study • Published 2010 • Determined the current standard of care for first line treatment of advanced CCA



ABC - 02 Outcomes Valle J et al. N Engl J Med 2010;362:1273 - 1281 Median Overall Survival Gem + Cis: Gem: 11.7 mos 8.1 mos Median Progression Free Survival Gem + Cis: Gem: 8.0 mos 5.0 mos



A Phase 3 randomized, double - blind, placebo - controlled study of durvalumab in combination with gemcitabine plus cisplatin in patients with advanced biliary tract cancer: TOPAZ - 1



TOPAZ - 1 study design



Primary endpoint: OS



Secondary endpoint: PFS



Secondary endpoint: Tumor response



Survival after 1 st Line Therapy • In ABC - 02 and Topaz - 1 median survival post progression was about 3 months



Unmet Need for Second Line Therapies for Cholangiocarcinoma ڻ Historical data of outcomes in 2L chemo - based therapies after gemcitabine/plat - based combo therapy failure result in dismal outcomes with limited progression free survival: Author Treatment Phase No. of patients PFS (mo) OS (mo) ORR (%) He et al. FOLFOX - 4 II 37 3.1 6.9 21.6 Paule et al. Gem/oxa + cetuximab II 9 4.0 7.0 11.0 Sasaki et al. Irinotecan II 13 1.8 6.7 7.7 Suzuki et al. S - 1 II 40 2.5 6.8 7.5 Fornaro et al. Gem combination Retrospective 174 3.0 6.6 3.4 Source: Ahn and Bekaii - Saab 2017* *OS (mo) reported from He et al. , and ORR (%) reported from Paule et al. and Fornaro et al. are corrected. 15



1L treatment Source: Adapted from NCCN guidelines Doublet chemo of gemcitabine + cisplatin (based on ABC - 02) Treatment Paradigm for BTC 1L treatment 2L treatment FOLFOX Pemigatinib (for pts with FGFR2 mutation) Ivosidenib (for pts with IDH1 mutation) PD - 1 Inhibitor (for pts with MSI - H tumors Participation in clinical trial



Targeted Therapy in BTC • IDH - 1 • Microsatellite Instability (MSI - H) • NTRK fusion • FGFR fusion 9.3% 4.3% 0.75% <0.50% Eligible for current targeted therapies ~14% Presented by:



Second - line FOLFOX chemotherapy versus active symptom control for advanced biliary tract cancer (ABC - 06): a phase 3, open - label, randomised, controlled trial Angela Lamarca, PhD, Prof Daniel H Palmer, PhD, Harpreet Singh Wasan, MD, Paul J Ross, PhD, Yuk Ting Ma, PhD, Arvind Arora, MD, Stephen Falk, MD, Roopinder Gillmore, PhD, Prof Jonathan Wadsley, MA, Kinnari Patel, PhD, Alan Anthoney, MD, Prof Anthony Maraveyas, PhD, Prof Tim Iveson, MD, Justin S Waters, PhD, Claire Hobbs, MSc, Safia Barber, BSc, W David Ryder, Grad.IS, Prof John Ramage, MD, Prof Linda M Davies, MSc, Prof John A Bridgewater, PhD, Prof Juan W Valle, MD The Lancet Oncology Volume 22 Issue 5 Pages 690 - 701 (May 2021) DOI: 10.1016/S1470 - 2045(21)00027 - 9 Copyright © 2021 ished by Elsevier Ltd. This is an Open Access article under the CC B 4. i se. Terms and Conditions



Figure 1 The Lancet Oncology 2021 2690 - 7 1DOI: (10.1016/S1470 - 2045(21)00027 - 9) Copyright © 2021 ished by Elsevier Ltd. This is an Open Access article under the CC B 4. i se. Terms and Conditions ABC - 06 Trial Schema



Median Survival The Lancet Oncology 2021 2690 - 7 1DOI: (10.1016/S1470 - 2045(21)00027 - 9) Copyright © 2021 ished by Elsevier Ltd. This is an Open Access article under the CC B 4. i se. Terms and Conditions Median Overall Survival ASC + FOLFOX: 6.2 mos ASC: 5.3 mos Patient selection explains The longer OS



Chemotherapy in BTC • NCCN Guidelines – First Line: Gem/Cis doublet • 26.1% ORR • 3.6 month increase in median OS vs. Gem alone (HR=0.64) • Valle, et al. (2010) – Second - line: FOLFOX • 5% ORR • 0.9 month increase in median OS vs. supportive care (HR=0.69) • Lamarca, et al. (2021) • Taxanes – Neither paclitaxel nor docetaxel are recommended by NCCN – Paclitaxel : No responses in a 15 patient first - line study [Jones, et al . ( 1996 )] – Docetaxel: No responses in a 17 patient first - and second - line study [Pazdur, et al. (1999)] – Nab - Paclitaxel is under investigation, but preferred first line regimen is Gem/Cis per NCCN Guidelines 21 DO NOT DISTRIBUTE WITHOUT PERMISSION | © 2022



There clearly are unmet needs in managing BTC Presented by:



CTX - 009 Update: Executive Summary ڻ Phase 1: 8 PRs in patients with advanced cancers both as a monotherapy and in combination with chemotherapy with an acceptable safety profile ڻ Phase 2 (Stage 1): CTX - 009 in combination with paclitaxel in patients with BTC is ongoing ڻ Interim update (data as of April 14, 2022) ڻ 24 patients with BTC have been enrolled and dosed ڻ As of 4/14; 10 PRs for a 42% ORR (10/24) ڻ Responses observed across all 4 BTC subtypes ڻ Median time on study is  6 months ڻ Adverse event profile similar to Phase 1 studies ڻ Phase 2 (Stage 2): Plan to initiate Stage 2 in the US in early Q3 DO NOT DISTRIBUTE WITHOUT PERMISSION | 2022 3



Phase 1b Combination Study with Chemo (N=17) ڻ 4 arms: ڻ 10.0 and 12.5 mg/kg CTX - 009 ڻ Irinotecan or paclitaxel ڻ Activity: ڻ 4 PRs, 3 confirmed, including a confirmed PR in pancreatic cancer ڻ 9 Stable Disease (SD) ڻ Overall Response Rate (ORR): 24% ڻ Clinical Benefit Rate (CBR): 77% (PR + SD) 4 DO NOT DISTRIBUTE WITHOUT PERMISSION | © 2022



36.8% 22.7% 16.3% 7.4% 0.0% - 0.7% - 10.4% - 12.7% - 17.0% - 18.3% - 19.7% - 20.6% - 28.0% - 31.4% - 34.9% - 41.4% - 61.6% - 30.0% - 40.0% - 50.0% - 60.0% - 70.0% - 80.0% - 10.0% - 20.0% 10.0% 0.0% 30.0% 20.0% 50.0% 40.0% 70.0% 60.0% 80.0% Tumor Growth (%) Patient Phase 1b Data (17 Patients) CTX - 009 + paclitaxel or CTX - 009 + irinotecan Phase 1b Combination Stud y Waterfall Plot 5 Waterfall of CTX - 009 (ABL001) Combination study as of November 30, 2021 (All Phase 1b Patients, 10mg/kg or 12.5 mg/kg) Gastric CRC Cholangio Pancreatic Other DO NOT DISTRIBUTE WITHOUT PERMISSION | © 2022



Drug - related adverse events observed in > 1 patient Total (n) Total (%) Grade 3 (n) Grade 3 (%) Hypertension* 5 29% 4 24% Pulmonary hypertension (all grade 1) 5 29% 0 0% Neutropenia** Anemia** Thrombocytopenia** 4 3 2 24% 18% 12% 3 3 2 18% 18% 12% Proteinuria 3 18% 0 0% Dyspnea 3 18% 0 0% Fatigue 3 18% 0 0% Anorexia 3 18% 0 0% Gingival edema (mucositis) 2 12% 0 0% Nausea 2 12% 1 6% Anal hemorrhage 2 12% 0 0% Phase 1b Combination Safety Data 6 *In clinical trials of bevacizumab, incidence of Grade 3 - 4 hypertension ranged between 5% - 18% (Avastin label). It is typically managed by anti - hypertensive drugs. **Labeled Grade 3/4 cytopenia events for concomitant chemotherapy agent: Irinotecan: 31.4% neutropenia, 4.5% anemia, 1.7% thrombocytopenia Paclitaxel: 52% neutropenia, 16% anemia, 7% thrombocytopenia DO NOT DISTRIBUTE WITHOUT PERMISSION | © 2022



Phase 2 Combination Study: CTX - 009 Plus Paclitaxel Phase 2 Study Design: ڻ Patients with biliary tract cancers after one or two prior therapies ڻ CTX - 009 at 10 mg/kg biweekly plus paclitaxel 80 mg/m 2 weekly 3 of 4 weeks ڻ Simon 2 Stage adaptive design: ڻ Stage 1: 21 patients  ORR ڻ Stage 2: if 3 or more PRs  Stage 2: 45 additional patients DO NOT DISTRIBUTE WITHOUT PERMISSION | © 2022 7



Phase 2 Combination Study Status ڻ November 1, 2021 (previously reported interim data) ڻ 24 patients had been enrolled; 17 patients evaluable for response ڻ Efficacy data: 5 PRs; 29% ORR ڻ April 14, 2022 (interim data) ڻ 24 patients enrolled; 22 patients evaluable for response ڻ Efficacy data: 10 PRs; 42% ORR ڻ Plan to proceed to Stage 2 in the US and Korea DO NOT DISTRIBUTE WITHOUT PERMISSION | © 2022 8



Phase 2: Patient Baseline and Demographics 24 Total Patients Age Median (years) 61.5 Gender, n(%) Male 14 (58%) Female 10 (42%) ECOG performance status, n(%) 0 13 (54%) 1 11 (46%) 24 Total Patients Prior systemic therapies, n(%) 1 11 (46%) 2 13 (54%) Prior Gem/Cis regimen 23 (96%) BTC subtype, n (%) Intrahepatic cholangiocarcinoma 9 (38%) Extrahepatic cholangiocarcinoma 3 (13%) Gallbladder cancer 7 (29%) Ampullary cancer 5 (21%) DO NOT DISTRIBUTE WITHOUT PERMISSION | 2022 9



Phase 2 Waterfall: ORR = 42%; CBR = 92% DO NOT DISTRIBUTE WITHOUT PERMISSION | 2022 10 - 1 - 7 - 7 - 9 - 12 - 12 - 17 - 17 - 19 - 20 - 23 - 33 - 33 - 37 - 38 - 41 - 43 - 44 - 44 - 52 - 57 - 60 - 50 - 40 - 30 - 20 - 10 0 1 2 3 4 5 6 7 8 9 10 13 14 15 16 17 18 19 20 21 22 Intrahepatic cholangiocarcinoma Extrahepatic cholangiocarcinoma Gallbladder cancer Ampullary cancer 0 Partial Responses: 9 confirmed 1 pending confirmation 2 patients were not evaluable (one missing post baseline scan; one had a scan outside of protocol window) Patient ID 11 12 Percent tumor decline



Swimmer Plot: Median Time on Study ~ 6 Months DO NOT DISTRIBUTE WITHOUT PERMISSION | 2022 11 Days on Treatment



Safety Data: Treatment - Related ≥ Grade 3 Adverse Events Event 24 total Patients N (%) Neutropenia 12 (50.0%) Hypertension 4 (16.7%) Anemia 3 (12.5%) Thrombocytopenia 2 (8.3%) Additional events observed in 1 patient: Intestinal perforation, Asthenia, Catheter site hemorrhage, Fatigue, Cholangitis, Abdominal infection, Bacterial gastritis, Pneumonia (fatal), Post - procedure hemorrhage, Decreased appetite, Cerebral hemorrhage, Proteinuria, Embolism Event Avastin (label) Paclitaxel (label) Neutropenia 52% Hypertension 5 - 18% Anemia 16% Thrombocytopenia 7% Additional events: Additional events: GI perforation, Hypersensitivity wound healing reactions, complications, infections, bleeding, Proteinuria, neuropathy hemorrhage DO NOT DISTRIBUTE WITHOUT PERMISSION | 2022 12 Phase 2 BTC study of CTX - 009 plus paclitaxel Avastin and paclitaxel label information



CTX - 009 Next Steps ڻ Initiate Stage 2 of the Phase 2 BTC study in the US in early Q3 ڻ Initiate Phase 2/3 study in patients with colorectal cancer in the third line setting in the US in Q4 2022 ڻ Initiate Phase 2 study in patients with advanced ovarian cancer in the US in Q1 2023 ڻ Continue to evaluate additional indications for CTX - 009 both as a monotherapy and in combination with chemotherapy DO NOT DISTRIBUTE WITHOUT PERMISSION | 2022 13



CTX - 009 Interim Phase 2 Stu dy Summary ڻ 24 patients with BTC have been enrolled and dosed ڻ 10 partial responses (PRs) for a 42% ORR in patients treated in the second - and third - line settings (54% of patient were treated in the 3 rd line setting) ڻ Other regimens in BTC: ڻ FOLFOX (NCCN guidelines): 5% ORR in the second - line setting ڻ TOPAZ - 1 (Phase 3 development): 26.7% ORR for Gem/Cis/Durvalumab (anti - PD - L1) in the first - line setting ڻ Median time on study approximately 6 months, with 7 patients ongoing ڻ Adverse event profile similar to Phase 1 DO NOT DISTRIBUTE WITHOUT PERMISSION | 2022 14