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Merus Merus Announces Financial Results for the Second Quarter and Provides Business Update August 5 , 2021 UTRECHT , The Netherlands and CAMBRIDGE , Mass . , Aug. 05 , 2021 ( GLOBE NEWSWIRE ) -- Merus N.V. ( Nasdaq : MRUS ) ( " Merus " , the " Company , " " we " , or " our " ) , a clinical - stage oncology company developing innovative , full - length multispecific antibodies ( Biclonics® and Triclonics® ) , today announced financial results for the second quarter that ended June 30 , 2021 and provided a business update . " We are encouraged by the interim results on Zeno in patients with NRG1 fusion cancers that we reported in the second quarter and remain focused on successful execution of our Zeno program and our other clinical trials , " said Bill Lundberg , M.D. , President , Chief Executive Officer of Merus . " We are planning to provide a clinical update on MCLA - 145 and MCLA - 158 later this year . " Clinical Programs Zenocutuzumab ( Zeno or MCLA - 128 : HER3 x HER2 Biclonics® ) Phase 2 part of the phase 1/2 trial continues : update planned by the first half of 2022 We shared interim clinical data of our zenocutuzumab ( Zeno ) program in patients with NRG1 fusion ( NRG1 + ) cancers at the American Society of Clinical Oncology ( ASCO ) 2021 Annual Meeting . The highlights from the presentation included : • As of the April 13 , 2021 , efficacy data cutoff , 61 patients with NRG1 + cancer were enrolled , including 45 patients evaluable for response . • Encouraging early clinical activity was observed , with confirmed partial responses by investigator review ( RECIST v1.1 ) in 42 % ( 5 of 12 ) patients with pancreatic cancer and in 29 % ( 13 of 45 ) patients across all NRG1 + tumor types treated . • One additional partial response was confirmed after the data cutoff date , which if included in the interim efficacy analysis , would increase the percentage of confirmed partial responses across all NRG1 + tumor types treated to 31 % ( 14 of 45 patients ) . • More than three quarters ( 34 of 45 ) of evaluable patients showed tumor reduction . In addition , 40 % ( 19 of 47 ) of all patients remained on therapy as of the data cutoff date . • Zeno continues to be well tolerated with a favorable safety profile . As of June 4 , 2021 , more than 70 patients had been treated in the eNRGy trial and Early Access Program ( EAP ) . We continue to be encouraged by the ongoing trial , rate of enrollment , observed clinical activity and safety profile , and plan to provide a clinical and regulatory program update by the first half of 2022 . In the second quarter of 2021 , we entered into collaborations with several companies and medical organizations in Israel , Italy and Spain with the goal of raising awareness of the eNRGy trial and providing access to molecular screening opportunities for eligible patients with cancers that may have NRG1 fusions . Merus is now working with more than ten different industry and academic collaborators across Asia , North America and Europe aimed to enhance testing for NRG1 fusions , to raise awareness of and support enrollment into the eNRGy trial . Details of the eNRGy trial can be found at www.ClinicalTrials.gov and Merus ' trial website at www.nrg1.com , or by calling 1-833 - NRG - 1234 . MCLA - 158 ( Lgr5 x EGFR Biclonics® ) : Solid Tumors Phase 1 trial continues with dose expansion cohorts : update planned for Q4'21 The phase 1 , open - label , multicenter clinical trial of MCLA - 158 is ongoing in the dose expansion phase . Enrollment of patients with gastro - esophageal and head - and - neck cancers continues , and preliminary evidence of antitumor activity has been observed . We plan to provide an update at a medical conference in the fourth quarter of 2021 . MCLA - 145 ( CD137 x PD - L1 Biclonics® ) : Solid Tumors Phase 1 trial continues : update planned for Q4'21 The phase 1 , open - label , single - agent clinical trial of MCLA - 145 is ongoing and consists of a dose escalation phase , to be followed by a planned dose expansion phase . MCLA - 145 is the first drug candidate co - developed under Merus ' global collaboration and license agreement with Incyte Corporation ( " Incyte " ) , which permits the development and commercialization of up to 11 bispecific and monospecific antibodies from the BiclonicsⓇ platform . Merus retains full rights to develop and commercialize MCLA - 145 , if approved , in the United States ; and Incyte holds full rights to develop and commercialize MCLA - 145 outside the United States . We plan to provide an update at a medical conference in the fourth quarter of 2021 . We published a report in Nature Communications in July titled " A human CD137xPD - L1 bispecific antibody promotes anti - tumor immunity via context dependent T cell costimulation and checkpoint blockade " demonstrating in preclinical models that MCLA - 145 potently activates T cells , even in the presence of suppressive conditions , as well as enhances T cell priming and promotes long - term T cell immunity . In addition , the antitumor activity of MCLA - 145 in in vivo models was superior to those of the current standard immune checkpoint inhibitor comparators and associated with recruitment and intratumoral expansion of CD8 + T cells .