Merck & Co., Inc.
Merck & Co., Inc. operates as a healthcare company worldwide. It offers human health pharmaceutical for various areas under the Keytruda, Keytruda Qlex, Welireg, Gardasil, ProQuad, M-M-R II, Varivax, Vaxneuvance, Capvaxive, RotaTeq, Pneumovax 23, Bridion, Prevymis, Dificid, Zerbaxa, Winrevair, Adempas/ Verquvo, Ohtuvayre, Lagevrio, Isentress/Isentress HD, Delstrigo, Pifeltro, Belsomra, Januvia, and Janumet brands. The company also provides veterinary pharmaceuticals, vaccines and health management solutions and services, such as livestock products under the Nuflor, Bovilis/Vista, Bovilis Cryptium, Banamine, Estrumate, Matrix, Resflor, Zuprevo, Revalor, Safe-Guard, M+Pac, Porcilis, Circumvent, Nobilis/Innovax, Paracox and Coccivac, Exzolt, Slice, Imvixa, Clynav, Aquavac/Norvax, Aquaflor, Flexolt brands; Allflex Livestock Intelligence solutions; and companion animal products under the Bravecto One-Month, Bravecto Injectable/Quantum, Bravecto TriUNO, Bravecto Plus, Sentinel Spectrum, Sentinel Flavor Tabs, Numelvi, Optimmune, Nobivac NXT, GilvetMab, Otomax, Mometamax, Mometamax Ultra, Posatex, Caninsulin/Vetsulin, Panacur, Safeguard, Regumate, Prestige, Scalibor/Exspot, Sure Petcare, and Home Again brands. It has development and commercialization agreement for three of Daiichi Sankyo's deruxtecan ADC candidates; AstraZeneca PLC to co-development and co-commercialize AstraZeneca's Lynparza products for multiple cancer types; licensed to develop, manufacture and commercialize LM-299, a novel investigational PD-1/VEGF bispecific antibody from LaNova; and collaboration agreement with Eisai Co., Ltd., Bayer AG, and Ridgeback Biotherapeutics LP, as well Moderna, Inc. Merck & Co., Inc. has strategic collaboration with Infinimmune, Inc. to discover and develop antibodies against multiple therapeutic targets. The company was founded in 1891 and is headquartered in Rahway, New Jersey.
What does it do?
Merck is one of the world's largest pharmaceutical companies — it discovers, makes, and sells medicines and vaccines that doctors prescribe to patients. Its biggest product is Keytruda, a cancer drug that helps the immune system attack tumors, used in over 40 different cancer types including lung and skin cancer. It also makes Gardasil, the vaccine that protects against HPV (the virus that causes cervical cancer), given to millions of teenagers worldwide. Think of Merck as the company behind some of the most important medicines sitting in hospital pharmacies and oncology clinics globally.
Keytruda is currently the best-selling drug in the entire world, generating over $25 billion a year on its own — that makes Merck's next move one of the most watched stories in healthcare investing. The catch is that Keytruda's US patent expires in 2028, meaning cheaper copycat versions will eventually eat into that revenue, so investors are intensely focused on whether Merck can build a new revenue engine before that happens. With a $294 billion market cap, what happens to Merck ripples across the entire healthcare sector.
How does it make money?
Merck makes most of its $65 billion in annual revenue by selling prescription drugs and vaccines to hospitals, clinics, and pharmacies in over 140 countries. Keytruda alone accounts for roughly 40% of total revenue, making it unusually dependent on one product. The company also earns meaningful revenue from its animal health division, which sells vaccines and medicines for livestock and pets — a quieter but steady business. Net income came in at $18.3 billion last year, meaning for every dollar of revenue, Merck kept about 28 cents as profit, which is strong for any industry.
Why do investors care?
The core growth story is Merck's race to diversify before Keytruda's patent cliff arrives in 2028. It recently acquired Prometheus Biosciences and made a $10.8 billion bet on Harpoon Therapeutics to build out its pipeline — these are bets on next-generation treatments in areas like heart disease, autoimmune conditions, and new cancer therapies. Winrevair, a newly approved treatment for a serious lung condition called pulmonary arterial hypertension, is an early sign that the pipeline is starting to deliver. For this story to work, at least two or three of these pipeline drugs need to become blockbusters before Keytruda revenue starts declining.
Deep Dive
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