Keytruda's Main FDA Approvals for Cancer
Keytruda (pembrolizumab), from Merck, is a PD-1 inhibitor approved for over 30 cancer indications, primarily solid tumors with high microsatellite instability (MSI-H), mismatch repair deficiency (dMRR), or high tumor mutational burden (TMB-H). It treats melanoma, non-small cell lung cancer (NSCLC), head and neck squamous cell carcinoma (HNSCC), classical Hodgkin lymphoma, urothelial carcinoma, microsatellite instability-high (MSI-H) colorectal cancer, and triple-negative breast cancer, often in advanced or metastatic stages, alone or combined with chemotherapy, radiation, or other drugs.[1]
How Keytruda Works Against These Cancers
It blocks the PD-1 protein on T-cells, preventing cancer cells from evading immune detection via PD-L1 binding. Approvals target tumors expressing PD-L1 (TPS ≥1% or CPS ≥1), MSI-H/dMMR (regardless of PD-L1), or TMB-H (≥10 mut/Mb). First approval was March 2014 for unresectable or metastatic melanoma.[1][2]
Most Common Cancers Treated in Practice
NSCLC leads usage (about 40% of prescriptions), followed by melanoma (15-20%) and HNSCC. It's also standard for endometrial cancer (MSI-H/dMMR), gastric cancer, and cervical cancer in frontline or recurrent settings.[3]
Approvals in Earlier-Stage Cancers
Keytruda extends to adjuvant therapy post-surgery: high-risk melanoma, NSCLC (after resection/platinum chemo), and HNSCC (post-chemoradiation). Neoadjuvant use occurs in triple-negative breast cancer and early-stage NSCLC.[1]
Basket Approvals for Rare or Tumor-Agnostic Cases
Solid tumors with MSI-H/dMMR or TMB-H get approval regardless of location (e.g., MSI-H colorectal, any MSI-H solid tumor). This covers rare cancers like MSI-H small bowel or biliary tract cancers.[1][2]
What Happens Without Keytruda's Key Biomarkers?
Patients without MSI-H, dMMR, TMB-H, or PD-L1 expression often don't qualify unless in specific combo regimens (e.g., NSCLC with chemo). Testing via IHC, NGS, or PCR is required.[1]
Keytruda vs. Opdivo: Which Cancers Do They Overlap On?
Both treat melanoma, NSCLC, HNSCC, Hodgkin lymphoma, and urothelial cancer, but Keytruda has broader MSI-H/dMMR/TMB-H tumor-agnostic nods and leads in breast/endometrial. Opdivo edges in renal cell carcinoma.[3]
When Does Keytruda's Patent Protection End?
Core U.S. patents expire around 2028, with pediatric exclusivity to 2029 and potential extensions via new indications. Challenges from Amgen, Samsung Bioepis, and others target formulation patents into 2036.[4]
[1] FDA.gov - Keytruda Label (https://www.accessdata.fda.gov/drugsatfda_docs/label/2024/125514s171lbl.pdf)
[2] Merck.com - Keytruda Indications (https://www.keytruda.com/)
[3] NCCN Guidelines v2.2024 (https://www.nccn.org/guidelines)
[4] DrugPatentWatch.com - Keytruda Patents (https://www.drugpatentwatch.com/p/tradename/KEYTRUDA)