FDA Approves First Companion Diagnostic for Expanded EGFR TKIs in NSCLC

The FDA has approved the cobas EGFR Mutation Test v2 as a companion diagnostic for EGFR TKIs in the treatment of patients with EGFR-mutated non­–small cell lung cancer (NSCLC), according to an announcement from Roche, the test developer.¹

This test is indicated for use as a companion diagnostic to aid in the detection of EGFR mutations in both tissue and plasma samples collected from patients with NSCLC. With cobas EGFR Mutation Test v2, results are made available in less than 8 hours, according to Roche. With the new approval, this is the first companion diagnostic test for expanded EGFR therapies in this disease.

Specifically, the claim expansion allows for the assay to be used for all of the currently FDA-approved EGFR TKIs targeting the EGFR mutations L858R and exon 19 deletions per the approved therapeutic product labeling. The claim will also allow for the test to be used as a companion diagnostic for any EGFR TKI targeting those same alterations that receives approval in the future without the need for individual clinical studies with the test to be conducted for each new therapy.

“Clinicians can now have greater confidence in the robustness, reliability, and proven clinical utility of the cobas EGFR Mutation Test v2 when evaluating [patients with] lung cancer who may benefit from targeted EGFR TKI therapies,” Neil Gunn, head of Sequencing Solutions at Roche.

The companion diagnostic is a real-time polymerase chain reaction (PCR) test that was developed to identify a total of 42 alterations in exons 18, 19, 20, and 21 of the EGFR gene, including T790M resistance mutation. Mutations are identified through DNA isolated from formalin-fixed paraffin-embedded tumor tissue or circulating tumor DNA in plasma derived from ethylenediamine tetraacetic acid anti-coagulated peripheral whole blood, according to Roche.

The cobas EGFR Mutation Test v2 has been validated as a companion diagnostic for EGFR TKIs in several clinical trials conducted in both the first- and second-line settings for patients with advanced NSCLC.²

In one study, a total of 345 samples were evaluated using the cobas EGFR Mutation Test v2; 103 samples were analyzed using the Therascreen EGFR Plasma RGQ PCR Kit. Over the course of 3 years, a total of 395 samples were collected from 324 patients. Eleven plasma samples were validated independently using the Cobas test at 3 different institutions, while 130 samples were evaluated using Stilla digital PCR. Data were collected for 54% (n = 175) of a total of 324 patients.³

Results demonstrated that the Cobas assay was superior to the Therascreen test; the former demonstrated 100% reproducibility. Digital PCR showed only 48% concordance with Cobas for exon 19 deletions, 83% for L858R mutations, and 58% for T79M mutations. Moreover, investigators noted that the liquid biopsies helped inform and change treatment when resistance developed and allowed EGFR mutations to still be identified when tissue biopsy results were not available.

“By approving a single test for a broad group of therapies, this new and innovative approach by the FDA can pave the way for future EGFR TKI therapies to utilize the cobas EGFR Mutation Test v2 to help identify patients for personalized medicine,” Gunn added in the release.

References

1. Roche receives FDA approval for the cobas EGFR Mutation Test v2 as the first companion diagnostic test for expanded EGFR TKI therapies in patients with non–small cell lung cancer. News release. Roche. October 29, 2020. Accessed October 30, 2020. https://bit.ly/37RlycO.
2. cobas^® EGFR mutation test v2. Roche. Accessed October 30, 2020. https://bit.ly/35ThNRD.
3. Heeke S, Benzaquen J, Hofman V, et al. Critical assessment in routine clinical practice of liquid biopsy for EGFR status testing in non–small­–cell lung cancer: a single-laboratory experience (LPCE, Nice, France). Clin Lung Cancer. 2020;21(1):56-65.e8. doi:10.1016/j.cllc.2019.07.010