In recent years, five new immunotherapy drugs have been approved to treat patients diagnosed with urinary cancer. But the drugs, which held promise for replacing standard chemotherapy treatment, shrank tumors in only 15 to 20 percent of patients.
An international Phase II trial led by MD Anderson researchers may provide an alternative. The trial showed that treatment with the oral FGFR inhibitor erdafitinib (ERDA) was well-tolerated and achieved a robust response for patients with metastatic urinary tract cancers that harbor mutations in the FGFR3 gene.
The targeted therapy also appeared effective in a subset of patients for whom immunotherapy had previously failed, suggesting ERDA may provide benefit for patients without further treatment options. The results, presented by principal investigator Arlene Siefker-Radtke, M.D., professor of Genitourinary Medical Oncology, were granted the “Best of ASCO” designation.
“Given the limited treatment options for urinary tract cancer, we still have a long way to go to benefit our patients,” Siefker-Radtke says. “ERDA, with its response rate around 40 percent, and with its convenience of being an oral medication, certainly fits an unmet need.”
Erdafitinib is an oral medication that blocks activity of all FGFR proteins, including FGFR3. Genetic alterations in FGFR3 are found in 15 to 20 percent of patient who have metastatic bladder cancer and are thought to drive development of the disease. Further, tumors with FGFR3 mutations do not appear to display signs of immune activation, and there is growing evidence suggesting these tumors may not respond as well to immunotherapy, Siefker-Radtke explains.
“We will need confirmation in future studies, but there may be more benefit from an FGFR-targeted therapy in patients with an FGFR alteration as compared to immunotherapy,” Siefker-Radtke says. “It’s an exciting time, as we are heading into the field of personalized therapy for urothelial cancer.”