RESUMEN
Importance: The oral pan-fibroblast growth factor receptor inhibitor rogaratinib previously demonstrated encouraging safety and efficacy in a phase 1 study of patients with urothelial cancer (UC) overexpressing FGFR messenger RNA (mRNA). Objective: To evaluate the safety, pharmacokinetics, and preliminary efficacy of rogaratinib in combination with the programmed cell death 1 ligand 1 (PD-L1) inhibitor atezolizumab in cisplatin-ineligible patients with FGFR mRNA-positive, locally advanced/metastatic UC. Design, Setting, and Participants: The FORT-2 nonrandomized clinical trial was an open-label, single-arm, multicenter study conducted between May 15, 2018, and July 16, 2021, in 30 centers across Asia, Europe, and North America. Eligible patients had locally advanced/metastatic UC with FGFR1/3 mRNA overexpression and were ineligible for cisplatin-based chemotherapy. The data analysis was completed from July 2022 to September 2022. Interventions: Patients received rogaratinib 600 mg or rogaratinib 800 mg twice daily in combination with intravenous atezolizumab 1200 mg every 21 days. Main Outcomes and Measures: Primary end points included safety, tolerability, and the recommended phase 2 dose (RP2D) of rogaratinib in combination with atezolizumab. Results: Among 153 patients screened, 73 (48%) had tumors with FGFR1/3 mRNA overexpression, and 37 patients were enrolled and treated (median [range] age, 75.0 [47.0-85.0] years; 32 [87%] male). The most common treatment-emergent adverse events (TEAEs) included diarrhea in 23 patients (62%), hyperphosphatemia in 19 (51%), and fatigue in 15 (41%). Grade 3 or higher TEAEs were reported in 27 patients (73%), and 4 grade 5 TEAEs were reported, though unrelated to treatment. The RP2D was rogaratinib 600 mg in combination with atezolizumab 1200 mg. At the RP2D, the overall response rate was 53.8% in the rogaratinib 600 mg group, including 4 patients (15%) with complete responses; 12 responders (86%) did not have an FGFR3 gene alteration, and 11 (79%) had low PD-L1 expression. Conclusions and Relevance: In this phase 1b nonrandomized clinical trial, rogaratinib plus atezolizumab demonstrated a manageable safety profile, with no unexpected safety signals. Efficacy for this combination at the RP2D was observed in tumors with low PD-L1 and was not dependent on FGFR3 gene alterations, suggesting broad potential benefit for patients with locally advanced/metastatic UC and FGFR mRNA overexpression. Trial Registration: ClinicalTrials.gov Identifier: NCT03473756.
RESUMEN
PURPOSE: Rogaratinib, an oral pan-fibroblast growth factor receptor (FGFR1-4) inhibitor, showed promising phase I efficacy and safety in patients with advanced urothelial carcinoma (UC) with FGFR1-3 mRNA overexpression. We assessed rogaratinib efficacy and safety versus chemotherapy in patients with FGFR mRNA-positive advanced/metastatic UC previously treated with platinum chemotherapy. METHODS: FORT-1 (ClinicalTrials.gov identifier: NCT03410693) was a phase II/III, randomized, open-label trial. Patients with FGFR1/3 mRNA-positive locally advanced or metastatic UC with ≥ 1 prior platinum-containing regimen were randomly assigned (1:1) to rogaratinib (800 mg orally twice daily, 3-week cycles; n = 87) or chemotherapy (docetaxel 75 mg/m2, paclitaxel 175 mg/m2, or vinflunine 320 mg/m2 intravenously once every 3 weeks; n = 88). The primary end point was overall survival, with objective response rate (ORR) analysis planned following phase II accrual. Because of comparable efficacy between treatments, enrollment was stopped before progression to phase III; a full interim analysis of phase II was completed. RESULTS: ORRs were 20.7% (rogaratinib, 18/87; 95% CI, 12.7 to 30.7) and 19.3% (chemotherapy, 17/88; 95% CI, 11.7 to 29.1). Median overall survival was 8.3 months (95% CI, 6.5 to not estimable) and 9.8 months (95% CI, 6.8 to not estimable; hazard ratio, 1.11; 95% CI, 0.71 to 1.72; P = .67). Grade 3/4 events occurred in 37 (43.0%)/4 (4.7%) patients and 32 (39.0%)/15 (18.3%), respectively. No rogaratinib-related deaths occurred. Exploratory analysis of patients with FGFR3 DNA alterations showed ORRs of 52.4% (11/21; 95% CI, 29.8 to 74.3) for rogaratinib and 26.7% (4/15; 95% CI, 7.8 to 55.1) for chemotherapy. CONCLUSION: To our knowledge, these are the first data to compare FGFR-directed therapy with chemotherapy in patients with FGFR-altered UC, showing comparable efficacy and manageable safety. Exploratory testing suggested FGFR3 DNA alterations in association with FGFR1/3 mRNA overexpression may be better predictors of rogaratinib response.