Keytruda (pembrolizumab) is a medication used to treat various types of cancer, including melanoma, non-small cell lung cancer, head and neck squamous cell carcinoma, and others. According to [1], Keytruda has been shown to be effective in treating several types of cancer, with response rates ranging from 20% to 90%, depending on the type and stage of cancer.

One study cited on [2] showed that Keytruda had a success rate of 33% in patients with advanced non-small cell lung cancer who had previously received chemotherapy. The study found that patients who received Keytruda had a longer progression-free survival and overall survival compared to those who received chemotherapy alone.

Another study cited on [3] showed that Keytruda, when used in combination with chemotherapy, provided a sustained survival benefit versus chemotherapy alone in patients with metastatic non-small cell lung cancer. The five-year data from the study showed that the combination therapy resulted in a 27% reduction in the risk of death compared to chemotherapy alone.

It is important to note that the success rate of Keytruda can vary depending on a number of factors, including the type and stage of cancer, as well as individual patient factors. Additionally, Keytruda can have side effects, which should be discussed with a healthcare provider.

Sources:
[1] https://www.drugpatentwatch.com/p/biologics/tradename/KEYTRUDA
[2] https://www.drugs.com/medical-answers/success-rate-keytruda-3555529/
[3] https://www.merck.com/news/five-year-data-for-mercks-keytruda-pembrolizumab-plus-chemotherapy-showed-sustained-survival-benefit-versus-chemotherapy-alone-in-two-studies-for-metastatic-non-small-cell-lung-cancer-nsclc/