Fibroblast growth factor receptor (FGFR) inhibitor rogaratinib in patients with advanced pretreated squamous-cell non-small cell lung cancer over-expressing FGFR mRNA: The SAKK 19/18 phase II study.

BACKGROUND

Patients with advanced squamous-cell lung cancer (SQCLC) frequently (46%) exhibit tumor overexpression of fibroblast growth factor receptor (FGFR) messenger ribonucleic acid (mRNA). Rogaratinib is a novel oral pan-FGFR inhibitor with a good safety profile and anti-tumor activity in early clinical trials as a single agent in FGFR pathway-addicted tumors. SAKK 19/18 determined clinical activity of rogaratinib in patients with advanced SQCLC overexpressing FGFR1-3 mRNA.

METHODS

Patients with advanced SQCLC failing standard systemic treatment and with FGFR1-3 mRNA tumor overexpression as defined in the protocol received rogaratinib 600 mg BID until disease progression or intolerable toxicity. A 6-months progression-free survival rate (6mPFS) ≤15 % was considered uninteresting (H0), whereas a 6mPFS ≥38 % was considered promising (H1). According to a Simon 2-stage design, 2 out of 10 patients of the first stage were required to be progression-free at 6 months. Comprehensive Genomic Profiling was performedusing the Oncomine Comprehensive Assay Plus (Thermo Fisher Scientific).

RESULTS

Between July 2019 and November 2020, 49 patients were screened and 20 were classified FGFR-positive. Among a total of 15 patients, 6mPFS was reached in 1 patient (6.7 %), resulting in trial closure for futility after the first stage. There were 7 (46.7 %) patients with stable disease and 5 (33.3 %) patients with progressive disease. Median PFS was 1.6 (95 % CI 0.9-3.5) months and median overall survival (OS) 3.5 (95 % CI 1.0-5.9) months. Most frequent treatment-related adverse events (TRAEs) included hyperphosphatemia in 8 (53 %), diarrhea in 5 (33 %), stomatitis in 3 (20 %) and nail changes in 3 (20 %) patients. Grade ≥3 TRAEs occurred in 6 (40 %) patients. No associations between mutational profile and treatment outcome were observed.

CONCLUSION

Despite preliminary signals of activity, rogaratinib failed to improve PFS in patients with advanced SQCLC overexpressing FGFR mRNA. FGFR inhibitors in SQCLC remain a challenging field, and more in-depth understanding of pathway crosstalks may lead to the development of drug combinations with FGFR inhibitors resulting in improved outcomes.