Washington University School of Medicine

– CHS-114 demonstrates clinical efficacy and proof of mechanism in HNSCC in combination with toripalimab – – Confirmed partial response in heavily pretreated PD-1 refractory patient supports expansion in HNSCC and gastric cancer in combination with toripalimab – – A second-line Phase 1 dose optimization study in HNSCC and gastric cancer is ongoing; results expected in the first half of 2026– – Coherus to host investor and analyst call with study investigator, Dr. Douglas Adkins, Washington University, today at 4:30 p.m. Eastern Time– REDWOOD CITY, CA, USA I April 28, 2025 I Coherus BioSciences, Inc. (“Coherus,” NASDAQ: CHRS), today announced data from its ongoing Phase 1 clinical trial evaluating CHS-114, a selective, cytolytic anti-CCR8 antibody, as monotherapy and in combination with toripalimab in patients with recurrent/metastatic head and neck squamous cell carcinoma (HNSCC) evaluating two pharmacologically active doses of CHS-114 for dose optimization. These data are being presented at the 2025 American Association for Cancer Research (AACR) Annual Meeting, taking place April 25-30, 2025, in Chicago, Illinois. The data showed a confirmed partial response in a heavily pretreated PD-1 refractory patient, a > 50% depletion in CCR8+ Treg, and an increase in CD8+ T cells, consistent with anti-tumor activity and demonstrating proof of mechanism. Importantly, the safety profile was consistent with advanced disease and the known safety profile of toripalimab. These data support continued evaluation of CHS-114 in combination with other therapies, including toripalimab. Results support advancement and ongoing enrolment in Part 3 of the study evaluating CHS-114 with toripalimab in HNSCC (n = 40). CHS-114 is an afucosylated CCR8 monoclonal antibody and is the only known selective molecule designed to exclusively target human CCR8 with no off-target binding and preferentially kills CCR8+ Tregs within the tumor microenvironment while preserving CD8+ effector T cells and Tregs in normal tissue. “The data to date demonstrate a robust depletion of Treg cells in tumors, with a manageable safety profile, and a patient with a meaningful clinical response, which is highly encouraging,” said Rosh Dias, M.D., Coherus’ Chief Medical Officer. “Furthermore, the profound increase in CD8+ T cells, making these tumors immunologically hot, is exciting as it supports CHS-114 being combined with several treatment modalities including T Cell Engagers. Head and neck cancer is an important strategic focus for Coherus, but CHS-114 has the potential, based on its mechanism of action, to treat many solid tumors, including non-small cell lung cancer and other large, underserved immuno-oncology indications, like colorectal cancer. We look forward to sharing further head and neck and gastric cancer data in the first half of next year.” “One of the biggest challenges in oncology has been finding a treatment that depletes Treg cells and relieves immune suppression in the tumor without causing collateral autoimmune disease or affecting antitumor T cells,” said Douglas Adkins, M.D., Professor of Medicine, Director, Section of Head and Neck and Thyroid Medical Oncology, Division of Medical Oncology, Washington University School of Medicine. “These early clinical results are exactly what we’ve been hoping for and demonstrate CHS-114’s ability to remodel the tumor microenvironment in favor of anti-tumor activity. I am looking forward to exploring this treatment combination for solid tumor patients, even beyond head and neck.” Results from Phase 1b dose expansion trial evaluating CHS-114 monotherapy and with toripalimab in HNSCC This open-label Phase 1b clinical trial evaluated CHS-114 as a single-agent and in combination with toripalimab in 21 patients with advanced solid tumors including HNSCC. Patients received either CHS-114 alone or in combination with toripalimab (240 mg) q3w. The primary endpoint of the study was to determine dose limiting toxicities (DLTs) and treatment emergent adverse events (TEAEs), with the goal of identifying two recommended doses for expansion. Key secondary endpoints included objective response rate (ORR) based on investigator review per RECIST v1.1 as well as pharmacokinetics and pharmacodynamics (PK/PD). As of the data cutoff date of January 24, 2025: These results support continued evaluation of CHS-114 in combination with other drugs including toripalimab, with broad potential applications in many solid tumors with a high density of CCR8+ Treg cells. A second-line HNSCC dose optimization study of CHS-114 in combination with toripalimab in HNSCC and gastric cancer patients is ongoing, with anticipated results in the first half of 2026 The current study design is expected to address the regulatory requirements under Project Optimus 1 and support the recommendation of a phase 2 dose by early 2026. AACR 2025 Presentation Details Title: Phase 1 study of anti-CCR8 antibody CHS-114 with and without anti-PD-1 antibody toripalimab in patients with advanced solid tumors Lead Author: Francis Worden, M.D., University of Michigan Abstract #: CT038 Poster Session: Phase 0 and Phase 1 Clinical Trials Poster Section 49: Poster board 17 Date and Time: Monday, April 28, 2025, 9:00 a.m. – 12:00 p.m. CDT Conference Call Information for Investors and Analysts Coherus Chief Development Officer, Dr. Theresa LaVallee, and Chief Medical Officer, Dr. Rosh Dias, will host a presentation and discussion of new clinical data from the Phase 1 study with CHS-114 with and without anti-PD-1 antibody toripalimab with study investigator, Dr. Douglas Adkins of Washington University. When: Monday, April 28, 2025, starting at 4:30 p.m. Eastern Time Investors and analysts are invited to listen into a live audio webcast of the presentation. To access the conference call, please pre-register through the following link to receive dial-in information and a personal PIN to access the live call: https://register-conf.media-server.com/register/BI5eb6be782f004f9bb4e652903aabafe4 Please dial in 15 minutes early to ensure a timely connection to the call. Webcast: https://edge.media-server.com/mmc/p/yawixgnq An archived webcast will be available on the “Investors” section of the Coherus website at https://investors.coherus.com/events-presentations . About the CHS-114 Phase 1 Study The Phase 1 study (NCT05635643) is a dose escalation, dose optimization, and expansion study evaluating CHS-114 as a monotherapy and in combination with toripalimab, a next-generation PD-1 inhibitor. Arm 1a (first-in-human dose escalation) enrolled 20 patients with advanced solid tumors including 2 patients with HNSCC and evaluated multiple dose levels (5-1200 mg) of CHS-114 monotherapy. Arm 1b evaluated two pharmacologically active doses of CHS-114 monotherapy in 12 HNSCC patients with paired tumor biopsies. Arm 2 evaluated two pharmacologically active doses of CHS-114 with toripalimab in 7 patients. Arm 3 is evaluating two pharmacologically active doses of CHS-114 with toripalimab in 40 patients with second-line HNSCC. Primary objectives are to optimize the CHS-114 dose(s) for expansion and evaluate the safety of CHS-114 with toripalimab. Secondary objectives were to evaluate the safety, PK, and antitumor activity of CHS-114 with and without toripalimab and assess biomarkers, including changes in regulatory T cells (Tregs) and CD8+ T cells in paired tumor biopsies and other immune biomarkers. About CHS-114 CHS-114, an afucosylated, cytolytic CCR8 monoclonal antibody, is designed to selectively target human CCR8 and preferentially kill CCR8+ Tregs within the tumor microenvironment while preserving CD8+ effector T cells and Tregs in normal tissue. In preclinical studies, CHS-114 induced antibody-dependent cellular cytotoxicity (ADCC) and/or antibody-dependent cellular phagocytosis (ADCP) to deplete tumoral CCR8+ Tregs. In addition, treatment with CHS-114 alone reduced tumor growth in murine models, and enhanced antitumor activity was observed in combination with anti-PD-1 treatment. CHS-114 is currently being evaluated in combination with toripalimab in two Phase 1b clinical trials in patients with advanced solid tumors, including head and neck cancer (NCT05635643) and gastric cancer (NCT06657144). About Coherus BioSciences Coherus is a fully integrated commercial-stage innovative oncology company with an approved next-generation PD-1 inhibitor, LOQTORZI ® (toripalimab-tpzi), growing revenues and a promising pipeline that includes two mid-stage clinical candidates targeting liver, lung, head & neck, and other cancers. Our strategy is to grow sales of LOQTORZI in nasopharyngeal carcinoma and advance the development of new indications for LOQTORZI in combination with both our pipeline candidates as well as our partners’, driving sales multiples and synergies from proprietary combinations. Coherus’ immuno-oncology pipeline includes multiple antibody immunotherapy candidates focused on enhancing the innate and adaptive immune responses to enable a robust antitumor response and enhance outcomes for patients with cancer. Casdozokitug is a novel IL-27 antagonistic antibody currently being evaluated in multiple Phase 1/2 and Phase 2 studies in patients with advanced solid tumors including in non-small cell lung cancer and in hepatocellular carcinoma. CHS-114 is a highly selective cytolytic anti-CCR8 antibody currently in Phase 1 studies in patients with advanced solid tumors, including head and neck squamous cell carcinoma and gastric cancer. For more information about LOQTORZI, including the U.S. Prescribing Information and important safety information, please visit www.loqtorzi.com . SOURCE: Coherus BioSciences

KEYNOTE-689 marks the first positive trial in more than two decades for patients with resected locally advanced head and neck squamous cell carcinoma (LA-HNSCC) Results to be presented at American Association for Cancer Research (AACR) Annual Meeting 2025 during a Plenary Session and included in official meeting press program RAHWAY, NJ, USA I April 27, 2025 I Merck (NYSE: MRK), known as MSD outside of the United States and Canada, today announced results from the Phase 3 KEYNOTE-689 trial evaluating KEYTRUDA ® (pembrolizumab), Merck’s anti-PD-1 therapy, as a perioperative treatment regimen for patients with stage III or IVA, resected, locally advanced head and neck squamous cell carcinoma (LA-HNSCC). Results at the first interim analysis of the trial showed KEYTRUDA significantly improved event-free survival (EFS) as part of a perioperative treatment regimen with adjuvant standard of care (SOC) radiotherapy with or without cisplatin compared to adjuvant standard of care (SOC) radiotherapy with or without cisplatin alone in patients with resectable LA-HNSCC. These data are being presented for the first time today during a Plenary Session at the American Association for Cancer Research (AACR) Annual Meeting 2025 (Abstract #CT001) and were selected for the AACR press program. After a median follow-up of 38.3 months (range, 9.0-66.5), treatment with KEYTRUDA before surgery (neoadjuvant), then continued in combination with standard of care radiotherapy (with or without cisplatin) after surgery followed by KEYTRUDA alone (adjuvant), reduced the risk of EFS events by 34% (HR=0.66 [95% CI, 0.49-0.88]; p=.0022) in the combined positive score (CPS) ≥10 population, by 30% (HR=0.70 [95% CI, 0.55-0.89; p=.0014) in the CPS ≥1 population and by 27% (HR=0.73 [95% CI 0.58-0.92]; p=.0041) in the intent-to-treat (ITT) population, compared to adjuvant radiotherapy (with or without cisplatin) alone in the ITT population. Among the CPS ≥10 population, median EFS was 59.7 months in the KEYTRUDA plus SOC group (95% CI, 41.1-not reached) versus 26.9 months (95% CI, 18.3-51.5) in the SOC group. Among the CPS ≥1 population, median EFS was 59.7 months (95% CI, 37.9-not reached) in the KEYTRUDA plus SOC group versus 29.6 months (95% CI, 19.5-41.9) in the SOC group. In the ITT population, median EFS was 51.8 months (95% CI, 37.5-not reached) in the KEYTRUDA plus SOC group versus 30.4 months (95% CI, 21.8-50.1) in the SOC group. The safety profile of KEYTRUDA was consistent with that observed in previously reported studies; no new safety signals were identified. “As the first positive trial in over two decades for patients with resectable, locally advanced head and neck squamous cell carcinoma, the presentation of these landmark results marks an important moment for these patients and those who care for them,” said Dr. Ravindra Uppaluri, the study’s co-principal investigator, director of Head and Neck Surgical Oncology, Brigham and Women’s Hospital and Dana-Farber Cancer Institute. “KEYNOTE-689 represents a meaningful development with a potential to provide an option that helps certain patients with LA-HNSCC reduce the risk of recurrence and disease progression earlier in their treatment journey.” “The addition of immunotherapy using KEYTRUDA to standard of care surgery and adjuvant (chemo)radiotherapy resulted in a significant reduction in the risk of event-free survival events by 27%, compared with standard of care therapy alone,” said study co-principal investigator Dr. Douglas Adkins, Professor, Division of Oncology, Washington University School of Medicine in St. Louis. “These results are notable as they mark the first time an anti-PD-1 therapy has demonstrated a statistically significant and clinically meaningful improvement in event-free survival in the neoadjuvant and adjuvant setting in earlier stages of head and neck squamous cell carcinoma.” The study also showed a statistically significant improvement in major pathological response (mPR) rate, a key secondary endpoint, in patients with CPS ≥10 (difference in mPR rates: 13.7% [95% CI, 9.7-18.7]; p<0.00001), CPS ≥1 (9.8% [95% CI, 7.0-13.3]; p<0.00001) and in the ITT population (9.3% [95% CI, 6.7–12.8, P<.00001), compared to adjuvant radiotherapy alone. A trend toward improvement in overall survival (OS), another key secondary endpoint, was observed in patients with CPS ≥10 (HR=0.72 [95% CI, 0.52-0.98])at the time of this interim analysis for the KEYTRUDA plus standard of care regimen versus standard of care alone. The OS results did not reach statistical significance at the time of this interim analysis. Due to the statistical testing hierarchy, formal testing was not performed in the CPS ≥1 and ITT populations. OS will be evaluated at the next interim analysis. “As the 12 th positive pivotal trial for a KEYTRUDA-based regimen in earlier-stage cancers, the results from KEYNOTE-689 are a testament to our commitment to address an unmet need in this important area of research,” said Dr. Marjorie Green, senior vice president and head of oncology, global clinical development, Merck Research Laboratories. “These compelling results illustrate the potential of this regimen to change the landscape of care for certain patients facing this challenging disease. We are working with the FDA and other global authorities to bring this new option to patients as quickly as possible.” A supplemental Biologics License Application (sBLA) for KEYTRUDA based on data from KEYNOTE-689 is under priority review with the U.S. Food and Drug Administration (FDA), with a Prescription Drug User Fee Act (PDUFA), or target action, date of June 23, 2025. KEYTRUDA is currently approved as monotherapy and in combination regimens for appropriate patients with metastatic or unresectable, recurrent HNSCC in the U.S., Europe, China, Japan and other countries around the world. For more information, please see the “Selected KEYTRUDA ® (pembrolizumab) Indications in the U.S.” section below. Study design and additional data from KEYNOTE-689 KEYNOTE-689 is a randomized, active-controlled, open-label Phase 3 trial (ClinicalTrials.gov, NCT03765918 ) evaluating KEYTRUDA as neoadjuvant treatment and KEYTRUDA in combination with standard of care radiotherapy (with or without cisplatin) as adjuvant treatment in treatment-naïve patients with newly diagnosed, stage III or IVA resectable, locally advanced head and neck squamous cell carcinoma (LA-HNSCC). Efficacy outcomes are classified by programmed cell death ligand 1 (PD-L1) combined positive score (CPS) status. The primary endpoint is EFS, which is defined as the time from randomization to the first occurrence of radiographic disease progression; local or distant progression or recurrence; or death due to any cause. The secondary endpoints include OS, mPR, pathological complete response and safety. The study enrolled 714 patients who were randomized 1:1 to receive: The safety profile of KEYTRUDA was consistent with that observed in previously reported studies. Grade ≥3 treatment-related adverse events (TRAEs) occurred in 44.6% of patients receiving KEYTRUDA plus standard of care radiotherapy versus 42.9% of patients receiving standard of care radiotherapy alone. TRAEs led to death in 1.1% of patients receiving the KEYTRUDA regimen (n=4) and 0.3% of patients receiving standard of care radiotherapy (n=1). No new safety concerns were identified. Immune-mediated adverse events (AEs) of any grade occurred in 43.2% of patients receiving the KEYTRUDA regimen, most commonly hypothyroidism (24.7%). About head and neck cancer Head and neck cancer describes a number of different tumors that develop in or around the throat, larynx, nose, sinuses and mouth. Most head and neck cancers are squamous cell carcinomas that begin in the flat, squamous cells that make up the thin surface layer of the structures in the head and neck. Locally advanced head and neck squamous cell carcinoma (LA-HNSCC) is cancer that has grown outside the original location, but has not yet spread to distant parts of the body. There are several factors that greatly increase the risk of developing head and neck cancer, including tobacco and alcohol use and human papillomavirus (HPV). It is estimated there were more than 947,200 new cases of head and neck cancer diagnosed and over 482,400 deaths from the disease in 2022 globally. In the U.S., it is estimated there will be approximately 72,680 new cases of head and neck cancer diagnosed and more than 16,680 deaths from the disease in 2025. About Merck’s early-stage cancer clinical program Finding cancer at an earlier stage may give patients a greater chance of long-term survival. Many cancers are considered most treatable and potentially curable in their earliest stage of disease. Building on the strong understanding of the role of KEYTRUDA in later-stage cancers, Merck is evaluating our portfolio of medicines and pipeline candidates in earlier disease states, with more than 30 ongoing registrational studies across multiple types of cancer. About KEYTRUDA ® (pembrolizumab) injection, 100 mg KEYTRUDA is an anti-programmed death receptor-1 (PD-1) therapy that works by increasing the ability of the body’s immune system to help detect and fight tumor cells. KEYTRUDA is a humanized monoclonal antibody that blocks the interaction between PD-1 and its ligands, PD- L1 and PD-L2, thereby activating T lymphocytes which may affect both tumor cells and healthy cells. Merck has the industry’s largest immuno-oncology clinical research program. There are currently more than 1,600 trials studying KEYTRUDA across a wide variety of cancers and treatment settings. The KEYTRUDA clinical program seeks to understand the role of KEYTRUDA across cancers and the factors that may predict a patient’s likelihood of benefitting from treatment with KEYTRUDA, including exploring several different biomarkers. Selected KEYTRUDA ® (pembrolizumab) Indications in the U.S. Head and Neck Squamous Cell Cancer KEYTRUDA, in combination with platinum and fluorouracil (FU), is indicated for the first-line treatment of patients with metastatic or with unresectable, recurrent head and neck squamous cell carcinoma (HNSCC). KEYTRUDA, as a single agent, is indicated for the first-line treatment of patients with metastatic or with unresectable, recurrent HNSCC whose tumors express PD-L1 [Combined Positive Score (CPS) ≥1] as determined by an FDA-approved test. KEYTRUDA, as a single agent, is indicated for the treatment of patients with recurrent or metastatic HNSCC with disease progression on or after platinum-containing chemotherapy. Melanoma KEYTRUDA is indicated for the treatment of patients with unresectable or metastatic melanoma. KEYTRUDA is indicated for the adjuvant treatment of adult and pediatric (12 years and older) patients with Stage IIB, IIC, or III melanoma following complete resection. Non-Small Cell Lung Cancer KEYTRUDA, in combination with pemetrexed and platinum chemotherapy, is indicated for the first-line treatment of patients with metastatic nonsquamous non-small cell lung cancer (NSCLC), with no EGFR or ALK genomic tumor aberrations. KEYTRUDA, in combination with carboplatin and either paclitaxel or paclitaxel protein-bound, is indicated for the first-line treatment of patients with metastatic squamous NSCLC. KEYTRUDA, as a single agent, is indicated for the first-line treatment of patients with NSCLC expressing PD-L1 [Tumor Proportion Score (TPS) ≥1%] as determined by an FDA-approved test, with no EGFR or ALK genomic tumor aberrations, and is: KEYTRUDA, as a single agent, is indicated for the treatment of patients with metastatic NSCLC whose tumors express PD-L1 (TPS ≥1%) as determined by an FDA-approved test, with disease progression on or after platinum-containing chemotherapy. Patients with EGFR or ALK genomic tumor aberrations should have disease progression on FDA-approved therapy for these aberrations prior to receiving KEYTRUDA. KEYTRUDA is indicated for the treatment of patients with resectable (tumors ≥4 cm or node positive) NSCLC in combination with platinum-containing chemotherapy as neoadjuvant treatment, and then continued as a single agent as adjuvant treatment after surgery. KEYTRUDA, as a single agent, is indicated as adjuvant treatment following resection and platinum-based chemotherapy for adult patients with Stage IB (T2a ≥4 cm), II, or IIIA NSCLC. Malignant Pleural Mesothelioma KEYTRUDA, in combination with pemetrexed and platinum chemotherapy, is indicated for the first-line treatment of adult patients with unresectable advanced or metastatic malignant pleural mesothelioma (MPM). Classical Hodgkin Lymphoma KEYTRUDA is indicated for the treatment of adult patients with relapsed or refractory classical Hodgkin lymphoma (cHL). KEYTRUDA is indicated for the treatment of pediatric patients with refractory cHL, or cHL that has relapsed after 2 or more lines of therapy. Primary Mediastinal Large B-Cell Lymphoma KEYTRUDA is indicated for the treatment of adult and pediatric patients with refractory primary mediastinal large B-cell lymphoma (PMBCL), or who have relapsed after 2 or more prior lines of therapy. KEYTRUDA is not recommended for treatment of patients with PMBCL who require urgent cytoreductive therapy. Urothelial Cancer KEYTRUDA, in combination with enfortumab vedotin, is indicated for the treatment of adult patients with locally advanced or metastatic urothelial cancer. KEYTRUDA, as a single agent, is indicated for the treatment of patients with locally advanced or metastatic urothelial carcinoma: KEYTRUDA, as a single agent, is indicated for the treatment of patients with Bacillus Calmette-Guerin (BCG)-unresponsive, high-risk, non-muscle invasive bladder cancer (NMIBC) with carcinoma in situ (CIS) with or without papillary tumors who are ineligible for or have elected not to undergo cystectomy. Microsatellite Instability-High or Mismatch Repair Deficient Cancer KEYTRUDA is indicated for the treatment of adult and pediatric patients with unresectable or metastatic microsatellite instability-high (MSI-H) or mismatch repair deficient (dMMR) solid tumors, as determined by an FDA-approved test, that have progressed following prior treatment and who have no satisfactory alternative treatment options. Microsatellite Instability-High or Mismatch Repair Deficient Colorectal Cancer KEYTRUDA is indicated for the treatment of patients with unresectable or metastatic MSI-H or dMMR colorectal cancer (CRC) as determined by an FDA-approved test. Gastric Cancer KEYTRUDA, in combination with trastuzumab, fluoropyrimidine- and platinum-containing chemotherapy, is indicated for the first-line treatment of adults with locally advanced unresectable or metastatic HER2-positive gastric or gastroesophageal junction (GEJ) adenocarcinoma whose tumors express PD-L1 (CPS ≥1) as determined by an FDA-approved test. This indication is approved under accelerated approval based on tumor response rate and durability of response. Continued approval of this indication may be contingent upon verification and description of clinical benefit in the confirmatory trials. KEYTRUDA, in combination with fluoropyrimidine- and platinum-containing chemotherapy, is indicated for the first-line treatment of adults with locally advanced unresectable or metastatic HER2-negative gastric or gastroesophageal junction (GEJ) adenocarcinoma. Esophageal Cancer KEYTRUDA is indicated for the treatment of patients with locally advanced or metastatic esophageal or gastroesophageal junction (GEJ) (tumors with epicenter 1 to 5 centimeters above the GEJ) carcinoma that is not amenable to surgical resection or definitive chemoradiation either: Cervical Cancer KEYTRUDA, in combination with chemoradiotherapy (CRT), is indicated for the treatment of patients with FIGO 2014 Stage III-IVA cervical cancer. KEYTRUDA, in combination with chemotherapy, with or without bevacizumab, is indicated for the treatment of patients with persistent, recurrent, or metastatic cervical cancer whose tumors express PD-L1 (CPS ≥1) as determined by an FDA-approved test. KEYTRUDA, as a single agent, is indicated for the treatment of patients with recurrent or metastatic cervical cancer with disease progression on or after chemotherapy whose tumors express PD-L1 (CPS ≥1) as determined by an FDA-approved test. Hepatocellular Carcinoma KEYTRUDA is indicated for the treatment of patients with hepatocellular carcinoma (HCC) secondary to hepatitis B who have received prior systemic therapy other than a PD-1/PD-L1-containing regimen. Biliary Tract Cancer KEYTRUDA, in combination with gemcitabine and cisplatin, is indicated for the treatment of patients with locally advanced unresectable or metastatic biliary tract cancer (BTC). Merkel Cell Carcinoma KEYTRUDA is indicated for the treatment of adult and pediatric patients with recurrent locally advanced or metastatic Merkel cell carcinoma (MCC). Renal Cell Carcinoma KEYTRUDA, in combination with axitinib, is indicated for the first-line treatment of adult patients with advanced renal cell carcinoma (RCC). KEYTRUDA is indicated for the adjuvant treatment of patients with RCC at intermediate-high or high risk of recurrence following nephrectomy, or following nephrectomy and resection of metastatic lesions. Endometrial Carcinoma KEYTRUDA, in combination with carboplatin and paclitaxel, followed by KEYTRUDA as a single agent, is indicated for the treatment of adult patients with primary advanced or recurrent endometrial carcinoma. KEYTRUDA, as a single agent, is indicated for the treatment of adult patients with advanced endometrial carcinoma that is MSI-H or dMMR, as determined by an FDA-approved test, who have disease progression following prior systemic therapy in any setting and are not candidates for curative surgery or radiation. Tumor Mutational Burden-High Cancer KEYTRUDA is indicated for the treatment of adult and pediatric patients with unresectable or metastatic tumor mutational burden-high (TMB-H) [≥10 mutations/megabase (mut/Mb)] solid tumors, as determined by an FDA-approved test, that have progressed following prior treatment and who have no satisfactory alternative treatment options. This indication is approved under accelerated approval based on tumor response rate and durability of response. Continued approval for this indication may be contingent upon verification and description of clinical benefit in the confirmatory trials. The safety and effectiveness of KEYTRUDA in pediatric patients with TMB-H central nervous system cancers have not been established. Cutaneous Squamous Cell Carcinoma KEYTRUDA is indicated for the treatment of patients with recurrent or metastatic cutaneous squamous cell carcinoma (cSCC) or locally advanced cSCC that is not curable by surgery or radiation. Triple-Negative Breast Cancer KEYTRUDA is indicated for the treatment of patients with high-risk early-stage triple-negative breast cancer (TNBC) in combination with chemotherapy as neoadjuvant treatment, and then continued as a single agent as adjuvant treatment after surgery. KEYTRUDA, in combination with chemotherapy, is indicated for the treatment of patients with locally recurrent unresectable or metastatic TNBC whose tumors express PD-L1 (CPS ≥10) as determined by an FDA-approved test. Merck’s focus on cancer Every day, we follow the science as we work to discover innovations that can help patients, no matter what stage of cancer they have. As a leading oncology company, we are pursuing research where scientific opportunity and medical need converge, underpinned by our diverse pipeline of more than 25 novel mechanisms. With one of the largest clinical development programs across more than 30 tumor types, we strive to advance breakthrough science that will shape the future of oncology. By addressing barriers to clinical trial participation, screening and treatment, we work with urgency to reduce disparities and help ensure patients have access to high-quality cancer care. Our unwavering commitment is what will bring us closer to our goal of bringing life to more patients with cancer. For more information, visit http://www.merck.com/research/oncology . About Merck At Merck, known as MSD outside of the United States and Canada, we are unified around our purpose: We use the power of leading-edge science to save and improve lives around the world. For more than 130 years, we have brought hope to humanity through the development of important medicines and vaccines. We aspire to be the premier research-intensive biopharmaceutical company in the world – and today, we are at the forefront of research to deliver innovative health solutions that advance the prevention and treatment of diseases in people and animals. We foster a diverse and inclusive global workforce and operate responsibly every day to enable a safe, sustainable and healthy future for all people and communities. For more information, visit www.merck.com and connect with us on X (formerly Twitter) , Facebook , Instagram , YouTube and LinkedIn . SOURCE: Merck

An immunotherapy treatment helps patients live years longer without their cancer getting worse or coming back, a major phase III trial has found. Pembrolizumab kept cancer at bay for some patients for an average of 60 months (five years) compared to 30 months when added to standard-of-care, according to the international trial, presented at the American Association for Cancer Research (AACR) annual meeting. The Keynote-689 trial involved 192 sites in 24 countries around the world, including a team led by Professor Kevin Harrington at The Institute of Cancer Research, London and Royal Marsden NHS Foundation Trust. The trial, which was funded by MSD and led by researchers at Washington University School of Medicine, USA, tested the drug on newly-diagnosed locally-advanced head and neck cancers. Hundreds of thousands of patients are diagnosed with these cancers around the world each year. Of the 714 patients on the trial, 363 patients received pembrolizumab followed by standard-of-care and 351 received only the current standard-of-care – surgery to remove the tumour, followed by radiotherapy with or without chemotherapy. Standard-of-care has not changed for these patients in over 20 years, and more than half of patients are unlikely to survive to five years. The immunotherapy treatment worked particularly well for those with high levels of the immune marker, PD-L1, but it ‘dramatically’ increased the chance of remaining well without the disease progressing or coming back for all tumour types. After three years, 58 per cent of patients given pembrolizumab were alive and free of disease, compared with 46 per cent given standard treatment. Pembrolizumab works by taking the brakes off the immune system’s ability to attack cancer cells, and is already approved for use on its own or in combination with chemotherapy in head and neck cancer that has come back or spread around the body. Previous trials of the drug given in patients who have received chemoradiotherapy without surgery for locally-advanced disease have not been as successful. The researchers believe the drug has been so effective in this current trial because of its use prior to surgery and then as part of the post-operative treatment. The drug primes the immune system to attack the cancer before it is surgically removed, and the immune system is then ready to continue fighting it when it is targeted with post-surgery chemotherapy or radiotherapy. The researchers hope that regulators around the world will approve the use of pembrolizumab, in combination with surgery followed by radiotherapy, with or without chemotherapy, to treat this form of locally-advanced head and neck cancer. Professor Kevin Harrington, Professor of Biological Cancer Therapies at The Institute of Cancer Research, London, and Consultant Oncologist at The Royal Marsden NHS Foundation Trust, said: “For patients with newly-diagnosed, locally-advanced head and neck cancer, treatments haven’t changed in over two decades. Immunotherapy has been amazingly beneficial for patients with cancer that has come back or spread around the body but, until now, it hasn’t been as successful for those presenting for the first time with disease which has spread to nearby areas. This research shows that immunotherapy could change the world for these patients – it significantly increases the chance of remaining free of disease. “The results of this trial show that pembrolizumab dramatically increases the duration of disease remission – for years longer than the current standard treatments. It works particularly well for those with high levels of immune markers, but it’s really exciting to see that the treatment improves outcomes for all head and neck cancer patients, regardless of these levels.” Professor Kristian Helin, Chief Executive of The Institute of Cancer Research, London, said: “It’s great to see these excellent results. Immunotherapy continues to deliver and to learn that patients with immunotherapy added to their treatment plan had, on average, double the length of time free from evidence of disease compared to those without it – with some patients still yet to see their cancer return – is wonderful. I hope for a quick regulatory approval for this new treatment option for patients with head and neck cancer.” Laura Marston, 45, from Derbyshire joined the KEYNOTE-689 trial in 2019 following a diagnosis of stage 4 tongue cancer. Laura originally cut her tongue in 2018, which overtime became more painful and developed into an ulcer. When the ulcer wasn’t disappearing she saw her GP who referred her for a biopsy, five days later on the 20 May Laura was told she had cancer. She was later referred to The Royal Marsden NHS Foundation Trust where she met Professor Kevin Harrington and joined the KEYNOTE-689 trial. Laura said: “I was so excited to be on a clinical trial and knowing I was in the best hands was really reassuring. I underwent two rounds of immunotherapy before undergoing surgery on the 13 August 2019. “In the months following my surgery I had to relearn how to eat and talk again while also having 10 more infusions of immunotherapy, chemotherapy, and radiotherapy but my clinical team were amazing and went above and beyond for anything I needed. I am amazed I am still here, this treatment has given me the gift of life.”