The FDA recently approved new dosing guidelines of 400 mg of pembrolizumab (KEYTRUDA®, Merck) to be taken every six weeks. The current recommended dose of pembrolizumab is 200 mg every three weeks. This new dosing regimen is approved across all adult indications of pembrolizumab.
Pembrolizumab is FDA approved to treat several cancers including melanoma, non-small cell lung cancer, small cell lung cancer, head and neck squamous cell cancer, classical Hodgkin lymphoma, primary mediastinal large B-cell lymphoma, urothelial carcinoma, gastric cancer, cervical cancer, and esophageal cancer, among others. An immunotherapy, pembrolizumab blocks the programmed death receptor-1 (PD-1) pathway which allows T cells to attack cancer cells.
Approval was based on KEYNOTE-555 (NCT03665597), an international, single-arm, multi-center trial. One hundred and one patients with advanced or metastatic melanoma who had not received PD-1, PD-L1, or CTLA-4 inhibitor (other than CTLA-4 inhibitors in the adjuvant setting) therapy previously were enrolled in this study. Participants received a 400 mg dose of pembrolizumab every six weeks. In the first 44 patients enrolled in the study, the researchers found that they achieved an overall response rate of 39%.
As a single agent, the most common treatment-related adverse events reported in greater than 20% of patients include fatigue, musculoskeletal pain, decreased appetite, pruritus, diarrhea, nausea, rash, pyrexia, cough, dyspnea, constipation, pain, and abdominal pain.
Side effects of pembrolizumab plus chemotherapy that occurred in greater than 20% of patients include fatigue, nausea, constipation, diarrhea, decreased appetite, rash, vomiting, cough, dyspnea, pyrexia, alopecia, peripheral neuropathy, mucosal inflammation, and stomatitis.
For More Information
Clinicaltrials.gov (2020). Relative bioavailability study of subcutaneous injection versus intravenous infusion of pembrolizumab (MK-375) in participants with advanced melanoma (MK-3475-555/KEYNOTE-555). NLM Identifier: NCT03665597
FDA (2020). FDA approves new dosing regimen for pembrolizumab [news release]. Available at: https://www.fda.gov/drugs/drug-approvals-and-databases/fda-approves-new-dosing-regimen-pembrolizumab
KEYTRUDA® (pembrolizumab) prescribing information (2020). Merck. Available at: https://www.accessdata.fda.gov/drugsatfda_docs/label/2020/125514s059s064s076s083lbl.pdf
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