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COMPASS THERAPEUTICS Compass Therapeutics Reports Third Quarter 2021 Financial Results and Provides Corporate Update November 12 , 2021 • CTX - 009 ( DLL4 X VEGF - A bispecific ) is ready to advance to the second stage of a Phase 2a study based on 5 partial responses in 17 evaluable patients observed in the first stage of the study • Continued the advancement of CTX - 471 ( CD137 agonist ) in Phase 1b development and reported a second partial response in a patient with metastatic melanoma following the progression of this patient on an anti - PD - 1 ( nivolumab ) treatment • Raised $ 125 million in gross proceeds from recent public offering extending the company's cash runway into the fourth quarter of 2024 BOSTON -- ( BUSINESS WIRE ) -- Compass Therapeutics , Inc. ( Nasdaq : CMPX ) , a clinical - stage biopharmaceutical company developing proprietary antibody - based therapeutics to treat cancer , today reported financial results for the third quarter ended September 30 , 2021 and highlighted recent corporate accomplishments . " We have made major progress on reaching our corporate goals , highlighted by achieving significant advancements for both of our clinical stage programs and raising capital to support our objectives , " said Thomas J. Schuetz , MD , PhD , Co - founder and Chief Executive Officer . " We released promising interim Phase 2a data on our lead program , CTX - 009 , which support our conviction that CTX - 009 is a promising novel bispecific antibody therapy with activity across a broad range of solid tumors . Additionally , CTX - 471 continues to advance well in development , and has demonstrated encouraging activity as a monotherapy in the post anti - PD - 1 / PD - L1 patient population , an area of a particularly high unmet medical need . " " On the financing side , we completed a $ 125 million public offering and concurrently uplisted to Nasdaq , " added Vered Bisker - Leib , PhD , MBA , President and Chief Operating Officer . " We expect this offering will extend our cash runway into the fourth quarter of 2024 , which will support the advancement of our pipeline . These are significant achievements for Compass and position us well to grow and fund key milestones throughout the next several years . " Third Quarter Development Highlights : • CTX - 009 ( DLL4 and VEGF - A bispecific antibody ) : A Phase 2a study was initiated in Q1 2021 testing CTX - 009 in combination with paclitaxel in patients with Biliary Tract Cancers ( cholangiocarcinoma ) . Enrollment in the first part of the study has been completed and the criteria to advance to the second part of the study have been met . Notably , five partial responses ( PRS ) have already been observed among the first 17 patients evaluated leading to a preliminary overall response rate ( ORR ) of 29 % , and all patients evaluated have had stable disease or better with a decline in tumor burden observed in 16 of the 17 patients leading to a Clinical Benefit Rate ( CBR ) of 100 % . The study is being conducted in South Korea by Handok Pharmaceuticals and the clinicaltrials.gov identifier for the study is NCT04492033 . Compass plans to submit an Investigational New Drug ( IND ) application to the Food and Drug Administration ( FDA ) in the fourth quarter of 2021 and subject to the IND clearance with the FDA , to initiate a Phase 2 study in 2022 in the United States . • CTX - 471 ( monoclonal antibody agonist of CD137 , a key co - stimulatory receptor on immune cells ) : We initiated a Phase 1b dose expansion study for CTX - 471 in 2019 and treated 36 patients with 13 different tumor types in the study as of October 21 , 2021. Of the 25 evaluable patients in the dose expansion part of the study , two patients had a PR , one of which has been confirmed by RECIST 1.1 and the other PR has been seen at the first tumor evaluation at Week 9. 11 patients have reached stable disease , leading to a preliminary ORR of 8 % and a CBR of 52 % . The first PR observed in the study was in a patient with advanced small cell lung cancer who had a PR at Week 17 and this response was confirmed at Week 25. This patient has now been treated with CTX - 471 for more than one year with a durable PR . In October 2021 , a second PR was observed in a patient with metastatic melanoma who was previously treated with and progressed on nivolumab . We expect to complete the Phase 1b stage of this study during the first half of 2022 . • CTX - 8371 ( bispecific antibody that simultaneously targets both PD - 1 and PD - L1 ) : We initiated IND - enabling studies and the GMP manufacturing campaign for CTX - 8371 . Due in part to delays at our contract development manufacturing organization , we are currently targeting an IND submission in the second half of 2022 . Third Quarter Corporate Highlights :