Mobocertinib produces a “clinically meaningful benefit” in patients with previously treated, metastatic non-small cell lung cancer (mNSCLC) harboring EGFR exon 20 insertions (EGFRex20ins), according to researchers.
This finding, reported in JAMA Oncology, comes from the phase 1/2 trial that supported the recent US approval of mobocertinib.
The trial (ClinicalTrials.gov Identifier: NCT02716116) included patients with mNSCLC and EGFRex20ins who received mobocertinib at 160 mg once daily.
There were 114 patients who were previously treated with platinum chemotherapy and received mobocertinib in a dose-escalation cohort (n=6), a dose-expansion cohort (n=22), or an expansion cohort (n=86).
The full expansion cohort consisted of 96 patients, but 10 had not received platinum chemotherapy and were excluded from the platinum-pretreated cohort. The researchers reported results in the platinum-pretreated and expansion cohorts separately.
At baseline, the median age was 60 years (range, 27-84 years) in the platinum-pretreated cohort and 59 years (range, 27-80 years) in the expansion cohort. A majority of patients were women (66% and 65%, respectively), and most were Asian (60% and 69%, respectively).
The study’s primary endpoint was objective response rate (ORR) by independent review. Secondary endpoints included duration of response (DOR), progression-free survival (PFS), overall survival (OS), and safety.
In the platinum-pretreated cohort, the ORR was 28% by independent review and 35% by investigator assessment. The median DOR was 17.5 months, and the median time to response was 1.9 months. The median PFS was 7.3 months, and the median OS was 24.0 months.
In the expansion cohort, the ORR was 25% by independent review and 32% by investigator assessment. The median DOR was not estimable, and the median time to response was 1.9 months. The median PFS was 7.3 months, and the median OS was not reached.
The most common treatment-related adverse events (TRAEs) in both cohorts were diarrhea, rash, paronychia, decreased appetite, nausea, dry skin, and vomiting.
Grade 3 or higher TRAEs occurred in 47% of patients in the platinum-pretreated cohort and 42% of those in the expansion cohort. Treatment discontinuation due to any adverse event occurred in 17% and 10%, respectively.
“Mobocertinib appears to have a favorable risk-benefit profile in patients with previously treated EGFRex20ins-positive mNSCLC and may serve as a potential treatment option in this patient population, which has a high unmet medical need,” the researchers concluded.
Disclosures: This research was supported by Millennium Pharmaceuticals, Inc. Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of disclosures.
Zhou C, Ramalingam SS, Kim TM, et al. Treatment outcomes and safety of mobocertinib in platinum-pretreated patients with EGFR exon 20 insertion–positive metastatic non–small cell lung cancer. A phase 1/2 open-label nonrandomized clinical trial. JAMA Oncol. Published online October 14, 2021. doi:10.1001/jamaoncol.2021.4761
This article originally appeared on Cancer Therapy Advisor