What should I know about Merck & Co.?
Merck & Co. is a US pharmaceutical company based in Rahway, New Jersey, that develops and sells prescription medicines, vaccines and animal health products. It is known as MSD everywhere outside the United States and Canada, and it is a separate company from Germany's Merck KGaA. George Merck founded the company in 1891, and it entered animal health in 1950. Its best-known products include the cancer immunotherapy Keytruda and the HPV vaccine Gardasil. In the second quarter of 2026 it reported worldwide sales of $16.6 billion, up 5% on a year earlier.
What are Merck & Co.'s main drugs?
Keytruda (pembrolizumab) is by far Merck's biggest product. In the second quarter of 2026 Keytruda and its new subcutaneous version, Keytruda Qlex, earned $8.4 billion, and Gardasil $1.2 billion. Newer products include Winrevair, for pulmonary arterial hypertension (high blood pressure in the lungs), with sales of $588 million, and the pneumococcal vaccine Capvaxive, with $184 million. Keytruda made $16.4 billion in the first half of 2026 but loses patent protection in 2028, so Merck is working to replace that revenue.
What is Merck & Co. currently developing?
Merck says it expects to launch 20 new drugs by 2030 and has bought Verona Pharma (lung disease), Cidara Therapeutics (influenza) and Terns Pharmaceuticals (cancer). In the second quarter of 2026 the FDA approved Lipfendra (enlicitide), described as the first once-daily oral PCSK9 inhibitor, a cholesterol-lowering pill. The same update reported that a trial of sacituzumab tirumotecan, a cancer drug, met its main goals in endometrial cancer. A Phase 3 trial of islatravir with lenacapavir also showed sustained suppression of HIV.
Have there been any controversies involving Merck & Co.?
Merck's best-known controversy is the painkiller Vioxx. Merck withdrew it on 30 September 2004 after a trial showed it doubled the risk of heart attacks and strokes. In November 2007 the company agreed to pay $4.85 billion to settle about 47,000 personal-injury lawsuits. Merck stated that the deal was not a class action and that it was not admitting fault. The settlement required approval from most eligible claimants and set criteria that plaintiffs had to meet to qualify, including having suffered a heart attack or stroke after taking the drug.
Is Merck & Co. publicly traded, and how big is it?
Yes. Merck is listed on the New York Stock Exchange under the ticker MRK. Its market value was about $350 billion on 6 October 2026. In the second quarter of 2026 it reported sales of $16.6 billion, and it now expects full-year 2026 sales of $66.3 billion to $67.3 billion. Its market value has risen about 34% so far in 2026, according to the same source.