Immunotherapies using engineered T cells have ushered in a new era in cancer treatment, but they have their limits. They may cause side effects or stop working, and they do not work at all against 90% of cancers.
(Reuters) -Merck & Co reported better-than-expected fourth-quarter results on Thursday on strong sales of its cancer immunotherapy Keytruda, now the world's biggest selling prescription medicine. Keytruda sales rose 21% to $6.6 billion as the company was able to increase use of the drug in earlier stage cancers, topping analyst forecasts of $6.5 billion. For the full year, Keytruda generated $25 billion, surpassing sales of AbbVie's blockbuster arthritis drug Humira at its peak.