Arlene O. Siefker-Radtke, MD, on Metastatic Urothelial Carcinoma: New Data on Erdafitinib vs Chemotherapy From the THOR Study
2023 ASCO Annual Meeting
Arlene O. Siefker-Radtke, MD, of The University of Texas MD Anderson Cancer Center, discusses phase III findings showing that for patients with advanced or metastatic urothelial carcinoma and FGFR alteration who already had been treated with a PD-(L)1 inhibitor, erdafitinib significantly improved overall and progression-free survival, as well as overall response rate, compared with investigator’s choice of chemotherapy (LBA4619).
Transcript
Disclaimer: This video transcript has not been proofread or edited and may contain errors.
Arlene O. Siefker-Radtke:
We now have results from the THOR clinical trial studying erdafitinib in patients who have metastatic surgically unresectable urothelial carcinoma, who've received prior therapy for their tumor. This is the first clinical trial, showing proof of concept benefit from FGF targeted therapy, compared to what's been observed with chemotherapy.
The design of the trial takes patients who've had prior treatment, typically chemotherapy with platinum or carboplatinum, and patients may have had an immune checkpoint inhibitor. There are two cohorts to this trial. The cohort being presented is the group of patients who've had a prior immune checkpoint inhibitor. Patients were randomized between either erdafitinib alone or single agent taxane, or vinflunine, which is approved in Europe. And the results of the trial looked quite good indeed, with it hitting on all three endpoints.
The primary endpoint of the trial was median overall survival, and erdafitinib came in with a statistically significant improvement in overall survival with a median overall survival of 12 months compared to single agent chemotherapy, which was around 7.8 months. We also saw evidence of benefit in progression-free survival and overall survival. The progression-free survival with erdafitinib was around five and a half months. Single agent chemotherapy was half that amount, and the objective response rate for erdafitinib was around 45%, so that's 45% PRs and CRs, while single agent chemotherapy had a response rate of around 11%.
The toxicity reported is similar to what has been observed with other clinical trials of FGF targeted therapy, and as a result of this work, erdafitinib is here to stay as part of the standard armamentarium for the treatment of our urothelial cancer patients.
The ASCO Post Staff
Shailender Bhatia, MD, of the University of Washington and Fred Hutchinson Cancer Center, discusses phase I/II results on the efficacy of nivolumab with or without ipilimumab in patients with recurrent or metastatic Merkel cell carcinoma. The study found that, for this rare and aggressive skin cancer, nivolumab showed clinical activity in advanced disease. However, these results from CheckMate 358 do not suggest an additional benefit with ipilimumab added to nivolumab (Abstract 9506).
The ASCO Post Staff
Narjust Florez, MD, of Dana-Farber Cancer Institute, and Filippo Gustavo Dall’Olio, MD, of Institut Gustave Roussy, discuss circulating tumor DNA tumor fraction, and its link to survival in patients with advanced non–small cell lung cancer (NSCLC) treated with maintenance durvalumab in the UNICANCER SAFIR02-Lung/IFCT1301 trial. Tumor fraction was positive in 16% of patients randomly assigned to receive durvalumab in the study. This population seems to have a limited benefit from maintenance durvalumab after induction chemotherapy (Abstract 2516).
The ASCO Post Staff
Allison Betof Warner, MD, PhD, of Stanford University Medical Center, and Zeynep Eroglu, MD, of H. Lee Moffitt Cancer Center and Research Institute, discusses phase II findings showing that in patients with BRAF-mutant metastatic melanoma, dabrafenib plus trametinib and navitoclax (DTN) was associated with a complete response rate of 20% and an overall response rate of 84%. Additionally, there was a trend toward improved overall survival in patients treated with DTN compared with dabrafenib plus trametinib alone; the difference in overall survival was more pronounced in patients with a smaller tumor burden (Abstract 9511).
The ASCO Post Staff
Muhit Özcan, MD, of Turkey’s Ankara University School of Medicine, discusses phase II findings from the waveLINE-004 study. It showed that the antibody-drug conjugate zilovertamab vedotin had clinically meaningful antitumor activity in patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL) who experienced disease progression after, or have been ineligible for, autologous stem cell transplantation and/or chimeric antigen receptor T-cell therapy (Abstract 7531).
The ASCO Post Staff
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