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
Jennifer L. Crombie, MD, of Dana-Farber Cancer Institute, discusses the historically poor outcomes for patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL). Her study examined real-world data on the use of novel therapies in this population and found that outcomes with second- and third-line regimens of polatuzumab vedotin-piiq plus bendamustine and rituximab and tafasitamab plus lenalidomide remain suboptimal, with worse outcomes particularly after chimeric antigen receptor T-cell therapy (Abstract 7552).
The ASCO Post Staff
Eunice S. Wang, MD, of Roswell Park Comprehensive Cancer Center, and Gregory Roloff, MD, of the University of Chicago, discuss data that are the first to demonstrate post–FDA approval efficacy and toxicity rates of brexucabtagene autoleucel in adults with relapsed or refractory B-cell acute lymphoblastic leukemia. Although the data may confirm high response rates associated with this agent, they also highlight the need for interventions to reduce associated toxicities (Abstract 7001).
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
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
Catherine C. Coombs, MD, of the University of California, Irvine, discusses prolonged pirtobrutinib therapy, which continues to demonstrate a safety profile amenable to long-term administration at the recommended dose without evidence of new or worsening toxicity signals. The safety and tolerability observed in patients on therapy for 12 months or more were similar to previously published safety analyses of all patients enrolled, regardless of follow-up (Abstract 7513).
