In April 2019, the FDA approved Balversa (erdafitinib; from Janssen), an FGFR kinase inhibitor, for the treatment of adults with advanced or metastatic urothelial carcinoma (bladder cancer) and a susceptible FGFR3 or FGFR2 genetic alteration, whose disease progressed after platinum-containing chemotherapy. This is the first targeted drug to be approved by the FDA for patients with these specific genetic alterations. At the same time, the FDA approved a companion diagnostic test, therascreen FGFR RGQ RT-PCR Kit, which is designed to identify patients with bladder cancer and FGFR mutations or alterations, which qualifies them to receive treatment with Balversa.
“We’re in an era of more personalized or precision medicine, and the ability to target cancer treatment to a patient’s specific genetic mutation or biomarker is becoming the standard,” said Richard Pazdur, MD, Director of the FDA’s Oncology Center of Excellence.
“Today’s approval represents the first personalized treatment targeting susceptible FGFR genetic alterations for patients with metastatic bladder cancer,” Dr. Pazdur added.
“FGFRs regulate important biological processes including cell growth and division during development and tissue repair. This drug works by targeting genetic alterations in FGFRs.”
The FDA approved Balversa based on a clinical trial of 87 patients with advanced or metastatic urothelial cancer and a susceptible FGFR3 or FGFR2 genetic alteration. All patients had at least 1 genetic alteration that included FGFR3 or FGFR2 gene mutations or FGFR gene fusions and their disease progressed after chemotherapy.
Overall, about 32% of the patients who received Balversa had a positive response to treatment, including 2.3% of patients who had complete response, meaning that their disease stopped progression for an average of 5.4 months. Responses to Balversa were observed even among the 25% of patients whose disease did not respond to previous treatment with a PD-L1 or PD-1 inhibitor—the current standard treatment for patients with advanced or metastatic bladder cancer.
The most common side effects with Balversa include mouth sores, fatigue, increased creatinine level, diarrhea, dry mouth, elevated levels of various important clinical markers, decreased appetite and altered sense of taste, decreased albumin and hemoglobin levels, and dry skin.