MSD’s Keytruda (ingredient: pembrolizumab) became a new treatment option for metastatic esophageal or gastroesophageal junction (GEJ) carcinomas that had no first-line therapy for decades...It is the first authorization for immunotherapy in the primary treatment of unresectable or metastatic esophageal squamous cell carcinoma (ESCC)...The MFDS said Keytruda could be used in combo with chemotherapy (platinum and fluoropyridine) in the first-line treatment of patients whose PD-L1 expression is positive (CPS≥10) with unresectable, locally advanced, or metastatic esophageal or HER2 minus GEJ carcinoma.

...Merck (NYSE: MRK), known as MSD outside the United States and Canada, today announced that KEYTRUDA, Merck’s anti-PD-1 therapy, has received two new approvals from the Japan Pharmaceuticals and Medical Devices Agency (PMDA). KEYTRUDA monotherapy is now approved for the treatment of patients whose tumors are PD-L1-positive, and have radically unresectable, advanced or recurrent esophageal squamous cell carcinoma (ESCC) who have progressed after chemotherapy....

Merck (NYSE: MRK), known as MSD outside the United States and Canada, today announced that KEYTRUDA, Merck’s anti-PD-1 therapy, has been approved by the National Medical Products Administration (NMPA) in China as monotherapy for the treatment of patients with locally advanced or metastatic esophageal squamous cell carcinoma (ESCC) whose tumors express PD-L1 (Combined Positive Score [CPS] ≥10)...

KEYTRUDA is a programmed death receptor-1 (PD-1)-blocking antibody indicated:…for the treatment of patients with locally advanced or metastatic esophageal or gastroesophageal junction (GEJ) (tumors with epicenter 1 to 5 centimeters above the GEJ) carcinoma that is not amenable to surgical resection or definitive chemoradiation either:…as a single agent after one or more prior lines of systemic therapy for patients with tumors of squamous cell histology that express PD-L1 (CPS ≥10) as determined by an FDA-approved test.

For patients with esophageal squamous cell carcinoma and PD-L1 CPS ≥10, pembrolizumab plus CT is recommended.

Esophageal and Esophagogastric Junction cancer: Preferred Regimens…Pembrolizumab...For second-line therapy for esophageal squamous cell carcinoma, with PD-L1 expression levels by CPS of ≥10…

Pembro + chemo vs chemo was superior for OS in pts with ESCC CPS ≥10 (median 13.9 vs 8.8 mo; HR 0.57; 95% CI, 0.43-0.75; P < 0.0001), ESCC (median 12.6 vs 9.8 mo; HR 0.72; 95% CI, 0.60-0.88; P = 0.0006), CPS ≥10 (median 13.5 vs 9.4 mo; HR 0.62; 95% CI, 0.49-0.78; P < 0.0001), and all pts (median 12.4 vs 9.8 mo; HR, 0.73, 95% CI, 0.62-0.86; P < 0.0001).

Pembro and chemo showed comparable OS as 2L therapy for esophageal AC/SCC in the global ITT cohort. Pembro showed favorable OS in SCC and CPS ≥10 groups in the global cohort and in all groups in the China cohort, in which most patients had SCC.

...DOR per RECIST 1.1 As Assessed By Investigator in Participants With ESCC Whose Tumors are PD-L1 Biomarker-Positive (CPS ≥10)...

In KEYNOTE-180, data in a small number of patients suggested that measures of inflammation, like PD-L1 and GEP, may enrich for responses to pembrolizumab. In SCC, some trends toward enrichment were observed for both biomarkers, although the trend was stronger for PD-L1 CPS ≥10 (tables 1, 2).

Pembro showed favorable OS in SCC and CPS ≥10 groups in the global cohort...