Merus NV

UTRECHT, The Netherlands and CAMBRIDGE, MA, USA I September 30, 2024 I 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 that the first patient has been dosed in the Company’s phase 3 trial evaluating the efficacy and safety of petosemtamab, a Biclonics ® targeting EGFR and LGR5, in combination with pembrolizumab, compared to pembrolizumab as first line (1L) therapy for patients with PD-L1+ recurrent/metastatic head and neck squamous cell carcinoma (r/m HNSCC), referred to as the LiGeR-HN1 trial. Merus has confirmed through feedback with the U.S. Food and Drug Administration (FDA) that petosemtamab 1500 mg every two weeks is appropriate for further development in HNSCC as monotherapy, and in combination with pembrolizumab. “Based on our strong phase 2 clinical data reported previously for petosemtamab in HNSCC both as monotherapy and in combination with pembrolizumab, I continue to be confident that petosemtamab has the opportunity to become a new standard of care across r/m HNSCC and potentially beyond,” said Bill Lundberg, M.D., President, Chief Executive Officer of Merus. “Our recently announced alignment with the FDA on phase 3 dose, and excellent execution to date has allowed us to promptly initiate our registration trials in 1L and 2/3L HNSCC.” More details of the trial can be found at clinicaltrials.gov. About LiGeR-HN1 LiGeR-HN1, a phase 3 trial, will evaluate the safety and efficacy of petosemtamab in combination with pembrolizumab, compared to pembrolizumab in 1L PD-L1+ r/m HNSCC patients. The trial is open to adult patients eligible to receive pembrolizumab as 1L monotherapy with tumors expressing PD-L1, CPS ≥1. The primary endpoints are overall response rate as assessed by BICR based on RECIST v1.1 and overall survival. Secondary endpoints are duration of response and progression free survival. Merus plans to enroll approximately 500 patients in the trial. About Petosemtamab Petosemtamab , or MCLA-158, is a Biclonics ® low-fucose human full-length IgG1 antibody targeting the epidermal growth factor receptor (EGFR) and the leucine-rich repeat containing G-protein-coupled receptor 5 (LGR5). Petosemtamab is designed to exhibit three independent mechanisms of action including inhibition of EGFR-dependent signaling, LGR5 binding leading to EGFR internalization and degradation in cancer cells, and enhanced antibody-dependent cell-mediated cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP) activity. About Head and Neck Cancer Head and neck squamous cell carcinoma (HNSCC) describes a group of cancers that develop in the squamous cells that line the mucosal surfaces of the mouth, throat, and larynx. These cancers begin when healthy cells change and grow in an unchecked manner, ultimately forming tumors. HNSCC is generally associated with tobacco consumption, alcohol use and/or HPV infections, depending on where they develop geographically. HNSCC is the sixth most common cancer worldwide and it is estimated that there were more than 930,000 new cases and over 465,000 deaths from HNSCC globally in 2020. 1 The incidence of HNSCC continues to rise and is anticipated to increase by 30% to more than 1 million new cases annually by 2030. 2 HNSCC is a serious and life-threatening disease with poor prognosis despite currently available standard of care therapies. 1 Sung et al. CA Cancer J Clin, 71:209-49, 2021; 2 Johnson, D.E., Burtness, B., Leemans, C.R. et al. Head and neck squamous cell carcinoma. Nat Rev Dis Primers 6, 92 (2020) About Merus N.V. Merus is a clinical-stage oncology company developing innovative full-length human bispecific and trispecific antibody therapeutics, referred to as Multiclonics ® . Multiclonics ® are manufactured using industry standard processes and have been observed in preclinical and clinical studies to have several of the same features of conventional human monoclonal antibodies, such as long half-life and low immunogenicity. For additional information, please visit Merus’ website , X , and LinkedIn . SOURCE: Merus

Petosemtamab in 2L+ HNSCC interim clinical data selected for rapid oral presentationUTRECHT, The Netherlands and CAMBRIDGE, Mass., Sept. 17, 2024 (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 the acceptance of an abstract on petosemtamab, a Biclonics® targeting EGFR and LGR5, in previously treated (2L+) patients with recurrent/metastatic head and neck squamous cell carcinoma (r/m HNSCC) for presentation at the European Society for Medical Oncology (ESMO®) Asia Congress 2024 taking place in Singapore December 6-8, 2024. Rapid oral presentation:Title: Petosemtamab (MCLA-158) monotherapy in previously treated (2L+) recurrent/metastatic (r/m) head and neck squamous cell carcinoma (HNSCC): Phase 2 trialAbstract #: 411MOSession Title: Mini Oral session: Head and Neck cancersSession Date and Time: December 7, 2024; 3:25-3:30 p.m. SGTLocation Hall: 404 The abstract will be available on the ESMO® Asia Congress website on Sunday, Dec. 1, 2024 at 11:05 a.m. ET. The full presentation will be available on the Merus website at the start of each session. Merus provided an interim clinical update on petosemtamab monotherapy in 2L+ HNSCC at the American Association of Cancer Research® (AACR®) Annual Meeting 2023, demonstrating a 37% response rate among 43 evaluable patients. The presentation at ESMO® Asia will include updated efficacy, durability and safety data from that initial 2L+ HNSCC cohort along with interim data from the dose optimization cohort evaluating petosemtamab monotherapy 1500 or 1100 mg dose levels in 2L+ HNSCC. Merus has confirmed through feedback with the U.S. Food and Drug Administration (FDA) that petosemtamab 1500 mg every two weeks is appropriate for further development in HNSCC as monotherapy, and in combination with pembrolizumab. Merus is currently enrolling LiGeR-HN2, a phase 3 trial evaluating the efficacy and safety of petosemtamab compared to investigator’s choice of single agent chemotherapy or cetuximab in previously treated (2/3L) patients with r/m HNSCC and plans to initiate LiGeR-HN1, a phase 3 trial evaluating petosemtamab in combination with pembrolizumab in frontline (1L) HNSCC by year end 2024. About PetosemtamabPetosemtamab, or MCLA-158, is a bispecific Biclonics® low-fucose human full-length IgG1 antibody targeting the epidermal growth factor receptor (EGFR) and the leucine-rich repeat containing G-protein-coupled receptor 5 (LGR5). Petosemtamab is designed to exhibit three independent mechanisms of action including inhibition of EGFR-dependent signaling, LGR5 binding leading to EGFR internalization and degradation in cancer cells, and enhanced antibody-dependent cell-mediated cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP) activity. About LiGeR-HN2LiGeR-HN2, a phase 3 trial, will evaluate the safety and efficacy of petosemtamab compared to investigator’s choice of methotrexate, docetaxel, or cetuximab in 2/3L r/m HNSCC patients. The trial is open to adult patients that have progressed on or after anti-PD-1 therapy and platinum-containing therapy. The primary endpoints are overall response rate as assessed by BICR based on RECIST v1.1 and overall survival. Secondary endpoints are duration of response and progression free survival. Merus plans to enroll approximately 500 patients in the trial. About Merus N.V.Merus is a clinical-stage oncology company developing innovative full-length human bispecific and trispecific antibody therapeutics, referred to as Multiclonics®. Multiclonics® are manufactured using industry standard processes and have been observed in preclinical and clinical studies to have several of the same features of conventional human monoclonal antibodies, such as long half-life and low immunogenicity. For additional information, please visit Merus’ website, X, and LinkedIn. Forward-Looking Statements This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. All statements contained in this press release that do not relate to matters of historical fact should be considered forward-looking statements, including without limitation statements regarding the clinical development of our clinical candidates, including petosemtamab, future clinical trial results or interim data, clinical activity and safety profile, and development plans in the on-going trials and described in forthcoming posters or presentations. These forward-looking statements are based on management’s current expectations. These statements are neither promises nor guarantees, but involve known and unknown risks, uncertainties and other important factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements, including, but not limited to, the following: our need for additional funding, which may not be available and which may require us to restrict our operations or require us to relinquish rights to our technologies or Biclonics®, Triclonics® and multispecific antibody candidates; potential delays in regulatory approval, which would impact our ability to commercialize our product candidates and affect our ability to generate revenue; the lengthy and expensive process of clinical drug development, which has an uncertain outcome; the unpredictable nature of our early stage development efforts for marketable drugs; potential delays in enrollment of patients, which could affect the receipt of necessary regulatory approvals; our reliance on third parties to conduct our clinical trials and the potential for those third parties to not perform satisfactorily; impacts of the market volatility; we may not identify suitable Biclonics® or bispecific antibody candidates under our collaborations or our collaborators may fail to perform adequately under our collaborations; our reliance on third parties to manufacture our product candidates, which may delay, prevent or impair our development and commercialization efforts; protection of our proprietary technology; our patents may be found invalid, unenforceable, circumvented by competitors and our patent applications may be found not to comply with the rules and regulations of patentability; we may fail to prevail in potential lawsuits for infringement of third-party intellectual property; and our registered or unregistered trademarks or trade names may be challenged, infringed, circumvented or declared generic or determined to be infringing on other marks. These and other important factors discussed under the caption “Risk Factors” in our Annual Report on Form 10-Q for the quarter ended June 30, 2024 filed with the Securities and Exchange Commission, or SEC, on August 1, 2024, and our other reports filed with the SEC, could cause actual results to differ materially from those indicated by the forward-looking statements made in this press release. Any such forward-looking statements represent management’s estimates as of the date of this press release. While we may elect to update such forward-looking statements at some point in the future, we disclaim any obligation to do so, even if subsequent events cause our views to change, except as required under applicable law. These forward-looking statements should not be relied upon as representing our views as of any date subsequent to the date of this press release. Biclonics®, Triclonics® and Multiclonics® are registered trademarks of Merus N.V.

BOSTON--( BUSINESS WIRE )-- Foundation Medicine, Inc. today announced a collaboration to develop Foundation Medicine’s RNA platform as a companion diagnostic for Merus N.V.’s (Nasdaq: MRUS) bispecific antibody zenocutuzumab (Zeno) to treat patients with neuregulin 1 fusion (NRG1+) cancer. Zeno is a Biclonics® that utilizes the Merus Dock & Block® mechanism to inhibit the neuregulin/HER3 tumor-signaling pathway in solid tumors with NRG1 fusions (NRG1+ cancer). Through its unique mechanism of binding to HER2 and potently blocking the interaction of HER3 with its ligand NRG1, Zeno has the potential to be particularly effective against NRG1+ cancer. In preclinical studies, Zeno potently inhibits HER2/HER3 heterodimer formation thereby inhibiting oncogenic signaling pathways, leading to inhibition of tumor cell proliferation and blocking tumor cell survival. In May the U.S. Food and Drug Administration (FDA) accepted under priority review a Biologics License Application for Zeno in patients with NRG1+ non-small cell lung (NSCLC) and NRG1+ pancreatic (PDAC) cancer. The FDA has also granted Breakthrough Therapy Designation (BTD) to Zeno for the treatment of patients with advanced unresectable or metastatic NRG1+ pancreatic cancer following progression with prior systemic therapy or who have no satisfactory alternative treatment options. Additionally, the FDA has granted BTD to Zeno for the treatment of patients with advanced unresectable or metastatic NRG1+ NSCLC, following progression with prior systemic therapy. NRG1 gene fusions are rare and have been identified in patients with different types of solid tumors, including NSCLC, pancreatic cancer, gallbladder cancer, renal cell carcinoma, bladder cancer, ovarian cancer, breast cancer, neuroendocrine tumor, sarcoma, and colorectal cancer. 1 NRG1 fusions are unique cancer drivers that create oncogenic chimeric ligands rather than the more widely described chimeric receptors (NTRK, RET, ROS1, ALK, and FGFR fusions). 2 While DNA sequencing with optimized targeting can detect fusions, Foundation Medicine’s RNA platform can provide another layer of sophisticated fusion detection in 318 genes through RNA sequencing. It also has expanded capabilities for research use to offer gene expression reporting of over 1,500 genes to support biomarker discovery. Foundation Medicine is the only company with FDA-approved CDx indications for fusion biomarkers using CGP tests, including approved claims using tissue or liquid biopsy for ALK, ROS1, RET, NTRK1/2/3, and FGFR2. 3 “We are excited to partner with Merus on this RNA companion diagnostic opportunity to provide fusion detection through next-generation sequencing,” says Troy Schurr, Chief Biopharma Business Officer at Foundation Medicine. “We anticipate this innovative molecular information will help detect more NRG1 fusions and provide healthcare providers with important information to inform their care decisions for patients.” About Foundation Medicine: Your Essential Partner in Cancer Care Foundation Medicine is a pioneer in molecular profiling for cancer, working to shape the future of clinical care and research. We collaborate with a broad range of partners across the cancer community and strive to set the standard for quality, scientific excellence, and regulatory leadership. Our deep understanding of cancer biology helps physicians make informed treatment decisions for their patients and empowers researchers to develop new medicines. Every day, we are driven to help our partners find answers and take action, enabling more people around the world to benefit from precision cancer care. For more information, please visit us on www.FoundationMedicine.com and follow us on LinkedIn and X . 1 Jonna S, Feldman RA, Swensen J, et al. Detection of NRG1 gene fusions in solid tumors. Clin Cancer Res . 2019;25(16):4966-4972. doi: 10.1158/1078-0432.CCR-19-0160 . 2 Suda K, Mitsudomi T. Emerging oncogenic fusions other than ALK , ROS1 , RET , and NTRK in NSCLC and the role of fusions as resistance mechanisms to targeted therapy. Transl Lung Cancer Res . 2020;9(6):2618-2628. doi:10.21037/tlcr-20-186 3 Data on file, Foundation Medicine, Inc. as of 2024.