On April 12, 2019, the FDA accelerated the approval of erdafitinib (Balversa; Janssen), a fibroblast growth factor receptor (FGFR) kinase inhibitor, for the treatment of adults with locally advanced or metastatic urothelial carcinoma and a susceptible FGFR3 or FGFR2 genetic alteration, as detected by an FDA-approved test, whose disease progressed after platinum-containing chemotherapy, making it the first targeted drug to receive approval for this patient population.
On the same day, the FDA approved the companion diagnostic test, therascreen FGFR RGQ RT-PCR Kit, to identify patients with bladder cancer and FGFR3 alterations who are candidates for erdafitinib therapy.
“Today’s approval represents the first personalized treatment targeting susceptible FGFR genetic alterations for patients with metastatic bladder cancer,” said Richard Pazdur, MD, Director of the FDA’s Oncology Center of Excellence.
“FGFRs regulate important biological processes including cell growth and division during development and tissue repair. This drug works by targeting genetic alterations in FGFRs,” Dr Pazdur added.
The FDA approved erdafitinib based on results from a phase 2, multicenter, single-arm clinical trial of 87 patients with locally advanced or metastatic urothelial cancer, with a susceptible FGFR3 or FGFR2 genetic alteration, that had progressed after chemotherapy.
In patients who received erdafitinib, the objective response rate was 32.2%, including 2.3% complete response, and the median duration of response was 5.4 months. Responses to erdafitinib were observed even among the 25% of patients who had not responded to previous anti–PD-L1/PD-1 therapy.
The most common (≥10%) adverse effects included increased phosphate level, stomatitis, fatigue, increased creatinine level, diarrhea, dry mouth, onycholysis, increased alanine aminotransferase level, increased alkaline phosphatase level, decreased sodium level, decreased appetite, decreased albumin level, altered sense of taste, decreased hemoglobin level, and dry skin.
