FDA Approves CDx for Cemiplimab in Non–Small Cell Lung Cancer

The FDA has expanded the use of the PD-L1 IHC 22C3 pharmDx assay to include the diagnosis of patients with non–small cell lung cancer (NSCLC), announced the developer, Agilent Technologies, Inc, in a press release.¹ 

FDA approval was granted to PD-L1 IHC 22C3 pharmDx as a companion diagnostic to identify patients with high tumor PD-L1 (Tumor Proportion Score ≥ 50%) expression who may benefit from treatment with cemiplimab-rwlc (Libtayo). Cemiplimab has been granted FDA approval for the first-line treatment of patients with advanced non-small cell lung cancer whose tumors have high PD-L1 expression, as determined by an FDA-approved test. Patients who receive cemiplimab for this indication must either have metastatic or locally advanced tumors that are not candidates for surgical resection or definitive chemoradiation, and the tumors must not have EGFR, ALK, or ROS1 aberrations.²

Cemiplimab-rwlc is a fully-human monoclonal antibody that targets PD-1 on T-cells, an immune checkpoint receptor. It blocks cancer cells from using the PD-1 pathway to suppress T-cell activation by binding to PD-1.¹

Cemiplimab is meant for patients with stage IVA-IVB NSCLC, for whom the 60-month survival rate is between 0% and 10%. In the phase 3 EMPOWER-Lung study, which led to the FDA approval of cemiplimab, the agent achieved a 22.1-month overall survival. The PD-L1 IHC 22C3 pharmDx kit was utilized during the study to measure PD-L1 expression at baseline.²

"Anti–PD-1 therapies, including Libtayo, continue to broaden the potential for the treatment of patients across different cancer types,” said Sam Raha, president, Diagnostics and Genomics Group, Agilent, in a press release.¹ "With the FDA approval of PD-L1 IHC 22C3 pharmDx as a companion diagnostic for treatment with Libtayo monotherapy in advanced NSCLC, Agilent further strengthens its ability to elevate pathologist confidence in reporting results to oncologists and bolsters our role as a global pioneer in developing companion diagnostics for targeted treatments."

According to Agilent, PD-L1 IHC 22C3 pharmDx has a high specificity and sensitivity. In the testing stage, the assay showed 100% overall agreement across its various tests. The results were reproducible, showing 85% overall agreement across tests. The specificity and sensitivity of the assay were also validated.³

In addition to cemiplimab, PD-L1 IHC 22C3 pharmDx is an FDA approved companion diagnostic for pembrolizumab (Keytuda) with an indication in triple-negative breast cancer, head and neck squamous cell carcinoma, urothelial carcinoma, cervical cancer, esophageal squamous cell carcinoma, gastric and gastroesophageal junction cancers, and NSCLC.

^REFERENCES:

^{1. Agilent PD-L1 IHC 22C3 pharmDx receives expanded FDA approval in non-small cell lung cancer (NSCLC). News release. Agilent Technologies, Inc. February 22, 2021. Accessed February 23, 2021. https://bit.ly/3usb1NR}

^{2. FDA approves Libtayo® (cemiplimab-rwlc) monotherapy for patients with first-line advanced non-small cell lung cancer with PD-L1 expression of ≥50%. News release. Regeron and Sanofi. February 22, 2021. Accessed February 23, 2021. https://bit.ly/2ZHfo9Y}

^{3. PD-L1 IHC 22C3 pharmDx Overview. Agilent Technologes, Inc. Accessed February 23, 2020. https://bit.ly/3sigRzJ}