In April, the drug erdafitinib (Balversa) became the first therapy targeting a genetic alteration to be approved by the Food and Drug Administration (FDA) to treat patients with metastatic urothelial carcinoma, the most common type of bladder cancer. FDA granted an accelerated approval to the drug, which blocks the activity of a family of proteins called fibroblast growth factor receptors (FGFR), for patients with specific FGFR gene alterations, based on preliminary data from a clinical trial. New findings from that trial have just been published. The updated results confirm that erdafitinib can benefit patients with advanced bladder cancer whose tumors have a genetic alteration in one of the four FGFR genes, according to Arlene Siefker-Radtke, M.D., of the University of Texas MD Anderson Cancer Center, who led the trial. In the study, erdafitinib decreased the tumors of some patients whose cancers did not respond to other treatments, the researchers reported in the New England Journal of Medicine on July 25. FDA’s approval covers patients whose cancer has spread outside of the bladder locally or to other parts of the body during or after treatment with standard chemotherapy. “Our patients with metastatic bladder cancer have very limited treatment options, and this represents a real unmet need,” Dr. Siefker-Radtke said. “Now that erdafitinib has been approved by the FDA, doctors can incorporate the drug into treatment strategies to benefit patients with FGFR-altered urothelial cancer,” she continued. “Additional research is ongoing to learn how to combine erdafitinib with immunotherapy drugs such as immune checkpoint inhibitors.” FDA has approved several checkpoint inhibitors for advanced bladder cancer, but only approximately 20% of patients benefit from these treatments, Dr. Siefker-Radtke noted. By comparison, 40% of the patients in the international phase 2 trial that led to the approval responded to erdafitinib, Dr. Siefker-Radtke and her colleagues reported. To confirm the study's results, a phase 3 clinical trial is comparing erdafitinib with standard chemotherapy and with the checkpoint inhibitor pembrolizumab (Keytruda) in patients with advanced bladder cancer whose tumors have an FGFR alteration.