Agilent Secures FDA Approval for PD-L1 IHC 22C3 pharmDx in Esophageal and GEJ Cancer

Agilent Technologies Inc. has received U.S. Food and Drug Administration (FDA) approval for PD-L1 IHC 22C3 pharmDx, Code SK006, as a companion diagnostic to identify patients with esophageal or gastroesophageal junction (GEJ) carcinoma who may be eligible for treatment with KEYTRUDA® (pembrolizumab), Merck’s anti-PD-1 therapy.

The diagnostic test is currently the only FDA-approved companion diagnostic indicated for identifying patients with esophageal or GEJ carcinoma whose tumors express PD-L1 with a Combined Positive Score (CPS) ≥ 1, making them eligible for treatment with KEYTRUDA. This latest approval represents the eighth FDA-approved indication for PD-L1 IHC 22C3 pharmDx, Code SK006, in combination with KEYTRUDA.

“With the expanded FDA approval of PD-L1 IHC 22C3 pharmDx in esophageal or GEJ carcinoma, Agilent is proud to support clinicians in identifying patients eligible for treatment with KEYTRUDA,” said Nina Green, vice-president and general manager of Agilent’s Clinical Diagnostics Division. “This milestone reinforces Agilent’s commitment to advancing precision medicine and underscores its leadership in delivering trusted companion diagnostics that help enable treatment with anti-PD-1 therapies.”

In addition to esophageal and GEJ carcinoma, the test is also approved to help identify patients who may benefit from KEYTRUDA across multiple cancers, including non-small cell lung cancer (NSCLC), esophageal squamous cell carcinoma (ESCC), cervical cancer, head and neck squamous cell carcinoma (HNSCC), triple-negative breast cancer (TNBC), gastric or GEJ adenocarcinoma, and epithelial ovarian, fallopian tube, or primary peritoneal carcinoma (EOC).

KEYTRUDA is indicated for patients with locally advanced or metastatic esophageal or GEJ carcinoma that cannot be treated with surgery or definitive chemoradiation. It is used in combination with platinum- and fluoropyrimidine-based chemotherapy for tumors expressing PD-L1 (CPS ≥ 1).

Esophageal cancer remains a significant health burden, accounting for approximately 16,250 deaths in the United States in 2025, with a five-year relative survival rate of 21.9%.

PD-L1 IHC 22C3 pharmDx, Code SK006, was developed by Agilent in collaboration with Merck (known as MSD outside the United States and Canada) as a companion diagnostic for KEYTRUDA.