FDA Approves Companion Diagnostic for Mobocertinib in Advanced NSCLC With EGFR Exon 20 Insertion Mutations

The FDA has approved FoundationOne® Liquid CDx as a companion diagnostic for mobocertinib (Exkivity) in patients with locally advanced or metastatic non–small cell lung cancer (NSCLC) harboring EGFR exon 20 insertion mutations.¹

In September 2021, the FDA granted accelerated approval to mobocertinib for the treatment of adult patients with locally advanced or metastatic NSCLC with EGFR exon 20 insertion mutations, as detected by an FDA-approved test, whose disease has progressed on or after platinum-based chemotherapy.²

“EGFR exon 20 insertion–positive NSCLC is a rare and historically underdiagnosed disease that requires a targeted treatment approach at the molecular level due to its unique mutation,” Stefanie Granado, head of the US Oncology Business Unit at Takeda, stated in a news release.¹ “The approval of this indication for Foundation Medicine’s blood-based companion diagnostic test is another important step forward to expand the identification of patients in the U.S. with this rare cancer and improve access for people who may benefit from treatment with [mobocertinib], including those unable to undergo tumor biopsy.”

FoundationOne Liquid CDx is a qualitative next-generation sequencing–based in vitro diagnostic test for use in patients with advanced solid tumors. Using circulating cell-free DNA, the test analyzes 324 genes. The diagnostic is approved by the FDA to report short variants in 311 genes.

The accelerated approval of mobocertinib was based on data from a cohort of 114 patients with EGFR exon 20 insertion–positive NSCLC who received prior platinum-based chemotherapy and received mobocertinib at a dose of 160 mg during the phase 1/2 Study 101 trial (NCT02716116).²

Patients in this cohort experienced a confirmed overall response rate (ORR) of 28% (95% CI, 20%-37%) per independent review committee (IRC) assessment. The median duration of response (DOR) was 17.5 months (95% CI, 7.4-20.3). Mobocertinib resulted in a median progression-free survival of 7.3 months (95% CI, 5.5-9.2) and a median overall survival of 24.0 months (95% CI, 14.6-28.8).

These patients enrolled in the international, non-randomized, open-label, multicohort Study 101 trial had an ECOG performance status of 0 or 1, and received at least 1 prior line of therapy for locally advanced/metastatic disease.³ Treatment with mobocertinib was continued until disease progression or unacceptable toxicity.

The primary end point was ORR per RECIST v1.1 criteria and by IRC assessment. Key secondary end points included safety, tolerability, pharmacokinetics, and efficacy.

Regarding safety, the most common adverse effects reported in more than 20% of patients consisted of diarrhea, rash, nausea, stomatitis, vomiting, decreased appetite, paronychia, fatigue, dry skin, and musculoskeletal pain.

Prescribing information for mobocertinib includes a boxed warning for QTc prolongation and Torsades de Pointes, as well as warnings and precautions for interstitial lung disease/pneumonitis, cardiac toxicity, and diarrhea.

References

1. FoundationOne Liquid CDx receives FDA-approval as a companion diagnostic for Exkivity (mobocertinib) to identify patients with EGFR exon 20 insertion mutations in advanced non-small cell lung cancer. News release. Foundation Medicine. May 4, 2023. Accessed May 4, 2023. https://www.foundationmedicine.com/press-releases/
2. Takeda's Exkivity (mobocertinib) approved by US FDA as the first oral therapy specifically designed for patients with EGFR exon20 insertion+ NSCLC. News release. Takeda Pharmaceutical Company. September 15, 2021. Accessed May 4, 2023. https://www.takeda.com/newsroom/newsreleases/2021/takeda-exkivity-mobocertinib-approved-by-us-fda
3. Ramalingam SS, Zhou C, Kim TM, et al. Mobocertinib (TAK-788) in EGFR exon 20 insertion (ex20ins)+ metastatic NSCLC (mNSCLC): additional results from platinum-pretreated patients (pts) and EXCLAIM cohort of phase 1/2 study. J Clin Oncol. 2021;39(suppl 15):9014. doi:10.1200/JCO.2021.39.15_suppl.9014