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
Amer Methqal Zeidan, MBBS, MHS, of Yale University and Yale Cancer Center, discusses phase III findings on the first-in-class telomerase inhibitor imetelstat, which was given to patients with heavily transfusion-dependent non-del(5q) lower-risk myelodysplastic syndromes that are resistant to erythropoiesis-stimulating agents. Imetelstat resulted in a significant and sustained red blood cell (RBC) transfusion independence in 40% of these heavily transfused patients. The response was also durable and accompanied by an impressive median hemoglobin rise of 3.6 g/dL, and seen in patients with and without ring sideroblasts. Importantly, reduced variant allele frequency was observed in the most commonly mutated myeloid genes which correlated with duration of transfusion independence and hemoglobin rise, therefore suggesting a disease-modifying potential of this agent (Abstract 7004).
The ASCO Post Staff
Narjust Florez, MD, of Dana-Farber Cancer Institute, and Heather A. Wakelee, MD, of Stanford University, Stanford Cancer Institute, discuss new data supporting neoadjuvant pembrolizumab plus chemotherapy followed by surgery and adjuvant pembrolizumab as a promising new treatment option for patients with resectable stage II, IIIA, or IIIB (N2) non–small cell lung cancer (NSCLC) (Abstract LBA100).
The ASCO Post Staff
Tycel J. Phillips, MD, and Alex F. Herrera, MD, both of the City of Hope National Medical Center, discuss results from the SWOG S1826 study, which showed that nivolumab and AVD (doxorubicin, vinblastine, and dacarbazine) improved progression-free survival vs brentuximab vedotin plus AVD in patients with advanced-stage classical Hodgkin lymphoma. Longer follow-up is needed to assess overall survival and patient-reported outcomes. This trial may be a key step toward harmonizing the pediatric and adult treatment of advanced-stage disease (LBA4).
The ASCO Post Staff
Shilpa Gupta, MD, of Cleveland Clinic, discusses the results from the EV-103 study and the unmet need for effective first-line therapies in cisplatin-ineligible patients with locally advanced or metastatic urothelial carcinoma. After nearly 4 years of follow-up, the trial findings showed that enfortumab vedotin-ejfv plus pembrolizumab continues to demonstrate promising survival trends with rapid and durable responses in this population (Abstract 4505).
The ASCO Post Staff
Narjust Florez, MD, of Dana-Farber Cancer Institute, and Ticiana Leal, MD, of Winship Cancer Institute of Emory University, discuss the use of tumor treating fields therapy, in which electric fields disrupt processes critical for cancer cell viability. Already approved by the FDA to treat glioblastoma and mesothelioma, the treatment has extended overall survival in this phase III study of patients with metastatic non–small cell lung cancer (NSCLC) with progression on or after platinum-based chemotherapy, without exacerbating systemic toxicities (Abstract LBA9005).
