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October 1, 2024 6:45 am ET Addition of CN201, a next generation CD3xCD19 bispecific antibody with potential applications in B-cell malignancies and autoimmune diseases, broadens and fortifies Merck’s pipeline RAHWAY, N.J.--(BUSINESS WIRE)-- Merck (NYSE: MRK), known as MSD outside of the United States and Canada, today announced the completion of the acquisition of CN201 from Curon Biopharmaceutical (Curon), a novel investigational clinical-stage bispecific antibody for the treatment of B-cell associated diseases. “By actively depleting B-cells, CN201 offers applications spanning both B-cell malignancies and autoimmune diseases. We look forward to building upon the foundational work started by the Curon team,” said Dr. Dean Y. Li, president, Merck Research Laboratories. CN201 is currently being investigated in Phase 1 and Phase 1b/2 clinical trials for the treatment of patients with relapsed or refractory non-Hodgkin’s lymphoma (NHL) and relapsed or refractory B-cell acute lymphocytic leukemia (ALL), respectively. Preliminary data suggest CN201 has activity in patients with relapsed or refractory B-cell hematologic malignancies and is well tolerated, potentially leading to significant and sustained reductions in B-cell populations. Transaction details Under the agreement, Merck, through a subsidiary, has acquired full global rights to CN201. As previously disclosed, the transaction is being accounted for as an asset acquisition. Merck is recording a pre-tax charge of approximately $750 million (reflecting the upfront payment and other related costs), or approximately $0.28 per share, which will be included in third-quarter non-GAAP results and was not included in Merck’s full-year financial outlook issued on July 30. As a matter of policy, Merck provides updates to its financial outlook once each quarter and will provide an update to its full-year financial outlook when it reports third-quarter 2024 results on October 31. About CN201 CN201 is a novel CD3xCD19-targeting T-cell-engager bispecific antibody, designed to target B cells for elimination by T cells. CN201 is currently being evaluated in Phase 1 and Phase 1b/2 clinical trials for the treatment of relapsed or refractory non-Hodgkin’s lymphoma and relapsed or refractory acute lymphocytic leukemia, respectively. 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 . Forward-Looking Statement of Merck & Co., Inc., Rahway, N.J., USA This news release of Merck & Co., Inc., Rahway, N.J., USA (the “company”) includes “forward-looking statements” within the meaning of the safe harbor provisions of the U.S. Private Securities Litigation Reform Act of 1995. These statements are based upon the current beliefs and expectations of the company’s management and are subject to significant risks and uncertainties. There can be no guarantees with respect to pipeline candidates that the candidates will receive the necessary regulatory approvals or that they will prove to be commercially successful. If underlying assumptions prove inaccurate or risks or uncertainties materialize, actual results may differ materially from those set forth in the forward-looking statements. Risks and uncertainties include but are not limited to, general industry conditions and competition; general economic factors, including interest rate and currency exchange rate fluctuations; the impact of pharmaceutical industry regulation and health care legislation in the United States and internationally; global trends toward health care cost containment; technological advances, new products and patents attained by competitors; challenges inherent in new product development, including obtaining regulatory approval; the company’s ability to accurately predict future market conditions; manufacturing difficulties or delays; financial instability of international economies and sovereign risk; dependence on the effectiveness of the company’s patents and other protections for innovative products; and the exposure to litigation, including patent litigation, and/or regulatory actions. The company undertakes no obligation to publicly update any forward-looking statement, whether as a result of new information, future events or otherwise. Additional factors that could cause results to differ materially from those described in the forward-looking statements can be found in the company’s Annual Report on Form 10-K for the year ended December 31, 2023 and the company’s other filings with the Securities and Exchange Commission (SEC) available at the SEC’s Internet site ( www.sec.gov ). Media Contacts: Robert Josephson (203) 914-2372 Carly Myar (917) 227-5957 Investor Contacts: Peter Dannenbaum (732) 594-1579 Damini Chokshi (732) 594-1577 Source: Merck & Co., Inc.

RAHWAY, N.J.--( BUSINESS WIRE )--Merck (NYSE: MRK), known as MSD outside of the United States and Canada, and Curon Biopharmaceutical (Curon), a privately held biotechnology company, today announced that the companies have entered into a definitive agreement under which Merck, through a subsidiary, has agreed to acquire CN201, a novel investigational clinical-stage bispecific antibody for the treatment of B-cell associated diseases. “ We continue to identify opportunities to expand and diversify our pipeline,” said Dr. Dean Y. Li, president, Merck Research Laboratories. “ Early clinical data have provided robust evidence for the potential of CN201 to target and deplete circulating and tissue B cells with the potential to treat a range of malignant and autoimmune diseases.” Under the terms of the agreement, Merck through a subsidiary will acquire full global rights to CN201 for an upfront payment of $700 million in cash. Curon is also eligible to receive up to $600 million in milestone payments associated with the development and regulatory approval of CN201. CN201 is currently being evaluated in Phase 1 and Phase 1b/2 clinical trials for the treatment of patients with relapsed or refractory non-Hodgkin’s lymphoma (NHL) and relapsed or refractory B-cell acute lymphocytic leukemia (ALL), respectively. Preliminary data suggest CN201 has activity in patients with relapsed or refractory B-cell hematologic malignancies and is well tolerated, with the potential to induce significant and sustained reductions in B-cell populations. Merck plans to evaluate CN201 as a treatment for B-cell malignancies as well as investigate its potential to provide a novel, scalable option for the treatment of autoimmune diseases. “ This agreement reflects the drive and dedication of the Curon team,” said Zhihong Chen, president and chief executive officer, Curon. “ As a pioneer in immuno-oncology, Merck is well positioned to build upon the work done to-date and investigate the wide-ranging, first-in-class potential of CN201.” Closing of the proposed transaction is subject to approval under the Hart-Scott-Rodino Antitrust Improvements Act and other customary conditions. The transaction is expected to close in the third quarter of 2024 and be accounted for as an asset acquisition. Merck expects to record a pre-tax charge of approximately $750 million (reflecting the upfront payment and other related costs), or approximately $0.28 per share, to be included in non-GAAP results in the quarter that the transaction closes. As a matter of policy, Merck provides updates to its financial outlook once each quarter and will provide an update to its full-year financial outlook when it reports third-quarter 2024 results. Advisors Hogan Lovells is serving as Merck’s legal advisor in this transaction. Centerview Partners LLC acted as financial advisor to Curon and Goodwin Procter LLP as the company’s legal advisor. About CN201 CN201 is a novel CD3xCD19-targeting T-cell-engager bispecific antibody, designed to target B cells for elimination by T cells. CN201 is currently being evaluated in Phase 1 and Phase 1b/2 clinical trials for the treatment of relapsed or refractory non-Hodgkin’s lymphoma and relapsed or refractory acute lymphocytic leukemia, respectively. About Curon Biopharmaceutical Curon Biopharmaceutical is a clinical-stage company developing bispecific antibodies and antibody-drug conjugates for the treatment of cancer, from both internal research and external collaborations. The company is a Cayman Islands incorporated company with operations in Australia, Hong Kong and Shanghai, China. 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 . Forward-Looking Statement of Merck & Co., Inc., Rahway, N.J., USA This news release of Merck & Co., Inc., Rahway, N.J., USA (the “company”) includes “forward-looking statements” within the meaning of the safe harbor provisions of the U.S. Private Securities Litigation Reform Act of 1995. These statements are based upon the current beliefs and expectations of the company’s management and are subject to significant risks and uncertainties. There can be no guarantees with respect to pipeline candidates that the candidates will receive the necessary regulatory approvals or that they will prove to be commercially successful. If underlying assumptions prove inaccurate or risks or uncertainties materialize, actual results may differ materially from those set forth in the forward-looking statements. Risks and uncertainties include but are not limited to, general industry conditions and competition; general economic factors, including interest rate and currency exchange rate fluctuations; the impact of pharmaceutical industry regulation and health care legislation in the United States and internationally; global trends toward health care cost containment; technological advances, new products and patents attained by competitors; challenges inherent in new product development, including obtaining regulatory approval; the company’s ability to accurately predict future market conditions; manufacturing difficulties or delays; financial instability of international economies and sovereign risk; dependence on the effectiveness of the company’s patents and other protections for innovative products; and the exposure to litigation, including patent litigation, and/or regulatory actions. The company undertakes no obligation to publicly update any forward-looking statement, whether as a result of new information, future events or otherwise. Additional factors that could cause results to differ materially from those described in the forward-looking statements can be found in the company’s Annual Report on Form 10-K for the year ended December 31, 2023 and the company’s other filings with the Securities and Exchange Commission (SEC) available at the SEC’s Internet site ( www.sec.gov ).