Investor Presentaiton

Driving value for patients and shareholders by progressing our pipeline Key regulatory milestones since the last earnings call: • In the U.S.: 。 FDA accepted for priority review the SNDA for WELIREG for the treatment of patients with advanced RCC immune checkpoint and anti-angiogenic therapies based on LITESPARK-005 。 FDA accepted for priority review the sBLA for KEYTRUDA in combination with concurrent chemoradiotherapy for the treatment of patients with newly diagnosed high-risk locally advanced cervical cancer based on KN-A18 o Received FDA approval for KEYTRUDA in the perioperative setting for the treatment of certain patients with resectable NSCLC based on KN-671 。 FDA approved KEYTRUDA for the treatment of adult and pediatric patients with recurrent locally advanced or metastatic Merkel cell cancer based on KN-017 and KN-913 。 FDA accepted for priority review the BLA for sotatercept for the treatment of patients with PAH based on STELLAR 。 FDA approved an expanded indication for ERVEBO for the prevention of disease caused by Zaire ebolavirus in individuals 12 months of age and older • In the EU: o Received EMA approval for KEYTRUDA in combination with trastuzumab and chemotherapy as 1L treatment in patients with HER2-positive advanced gastric or gastroesophageal junction adenocarcinoma in PD-L1 positive patients based on KN-811 o Received EMA approval for KEYTRUDA in patients with adjuvant NSCLC based on KN-091 o Received positive CHMP opinion for KEYTRUDA in combination with chemotherapy for 1L treatment of certain patients with locally advanced unresectable or metastatic HER2- gastric or GEJ adenocarcinoma based on KN-859 o Received EMA approval for an expanded indication for ERVEBO for active immunization of individuals 12 months of age and older to protect against Ebola Virus Disease (EVD) caused by Zaire ebolavirus • In Japan: o Received approval of Lynparza¹ in certain patients with BRCA-mutated castration-resistant prostate cancer 。 Accepted for review the sJNDA for KEYTRUDA in the perioperative setting for the treatment of patients with resectable NSCLC based on KN-671 1. In collaboration with AstraZeneca 2. Trial conducted in collaboration with Seagen and Astellas 3. In collaboration with Eisai 4. In collaboration with Moderna 5. In collaboration with Kelun-Biotech 6. In collaboration with Taiho and Astex Key data & clinical advancements since the last earnings call: Presented data across broad oncology portfolio at ESMO, including for KEYTRUDA (KN-A392, KN-671, KN-A18, KN- 522, KN-756, KN-811), Lenvima³, Lynparza¹, WELIREG (LITESPARK-005), V940/mRNA-41574 (INT), MK- 2870/SKB2645 (TROP2 ADC) and MK-10846 (KRAS G12C) Announced Phase 3 KN-123 trial met one of its dual primary endpoints of disease-free survival for the adjuvant treatment of patients with localized muscle-invasive urothelial carcinoma and locally advanced urothelial carcinoma after surgery Presented new analyses from studies of sotatercept at ERS, including post-hoc analysis of right heart catheterization and echocardiography data from the STELLAR study and interim analysis of the Phase 3 SOTERIA open-label extension study Advanced broad pipeline, including: o Initiated Phase 3 clinical program for MK-0616, an oral PCSK9 inhibitor 。 Poised to initiate Phase 3 trials for V9404 in NSCLC, MK-28705 in NSCLC and MK-7240 in UC MERCK 30

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