Arlene O. Siefker-Radtke, MD, presented “Erdafitinib Update – Metastatic Urothelial Cancer” at the 7th International Bladder Cancer Update on December 6, 2024, in Dallas, Texas.
How to cite: Siefker-Radtke, Arlene O. “Erdafitinib Update – Metastatic Urothelial Cancer” December 2024. Accessed Mar 2025. https://grandroundsinurology.com/erdafitinib-update-metastatic-urothelial-cancer/
Erdafitinib Update – Metastatic Urothelial Cancer – Summary
Arlene O. Siefker-Radtke, MD, explores the evolving role of erdafitinib in treating FGFR3-altered urothelial carcinoma. In this 12-minute presentation, Dr. Siefker-Radtke highlights erdafitinib, an FGFR3 inhibitor, as a second-line therapy following chemotherapy and immunotherapy.
Dr. Siefker-Radtke shares results from the THOR trial confirming its efficacy. While response rates were higher with erdafitinib, pembrolizumab exhibited greater long-term benefit, likely due to the durability of immunotherapy responses. Combination strategies with checkpoint inhibitors such as cetrelimab also showed promise. The RAGNAR trial further highlighted the drug’s tumor-agnostic potential.
The optimal sequencing of erdafitinib within treatment paradigms remains an open question, but emerging data suggest that its use following checkpoint inhibition maximizes therapeutic benefit while maintaining durable responses.
About the 7th International Bladder Cancer Update:
The International Bladder Cancer Update (IBCU) is a CME conference focused on the diagnosis and treatment of bladder cancer. The conference offers medical professionals an opportunity to listen to updates from, and interact with, expert international faculty to improve knowledge and determine best treatment practices to improve patient outcomes. IBCU encompasses expert lectures, interactive discussions, a panel roundtable, debates, and case presentations. It is physician-led, multi-supported, and designed for urologists, urologic oncologists, and other healthcare professionals involved in the treatment of bladder cancer.
For further educational activities from this conference, visit our collection page.
ABOUT THE AUTHOR

Arlene O. Siefker-Radtke
Arlene O. Siefker-Radtke, MD, earned her medical degree from The Johns Hopkins University School of Medicine. She completed a clinical residency in internal medicine at New England Medical Center, and a clinical fellowship in medical oncology at The University of Texas MD Anderson Cancer Center. Dr. Siefker-Radtke is board-certified in internal medicine and medical oncology. Dr. Siefker-Radtke is a Professor in the Department of Genitourinary Medical Oncology, Division of Cancer Medicine, at The University of Texas MD Anderson Cancer Center, where she has been exclusively focused on the treatment of urothelial cancer for over 20 years.
An active researcher, Dr. Siefker-Radtke has published over 150 journal articles, abstracts, editorials, and book chapters. She focuses on developing effective therapies for the treatment of urothelial cancer and other rare tumors of the bladder and upper tract. She is well known for her novel clinical trial designs, development of novel agents and targets including immunotherapy, fibroblast growth factor receptor inhibitors, development of neoadjuvant chemotherapy, and expertise in treating even the rarest tumors of the bladder.
Dr. Siefker-Radtke is actively involved in the Oncology Research Programs at National Comprehensive Cancer Network (NCCN). She currently serves as a member and Value Pathways Task Force member of the NCCN Bladder/Penile Cancers Panel, and on the National Institutes of Health (NIH) Bladder Cancer Task Force.