C-Reactive Protein-Albumin Ratio Predicts Objective Response to Enfortumab Vedotin in Metastatic Urothelial Carcinoma.

BACKGROUND: Enfortumab vedotin (EV), an antibody-drug conjugate that targets Nectin-4, is used for patients with metastatic urothelial carcinoma who have experienced progression on platinum-based chemotherapy and checkpoint inhibitors. Despite the widespread use of the drug, evidence remains scarce regarding clinical indicators that can predict the response to EV treatment. OBJECTIVE: We aimed to explore the predictive value of clinical indicators derived from peripheral blood tests for treatment responses to EV. METHODS: We utilized records of 109 patients with metastatic urothelial carcinoma treated by EV from our multi-institutional dataset. Receiver operating characteristic curve analyses for predicting objective responses including several indicators from blood examinations, such as C-reactive protein-albumin ratio (CAR), hemoglobin, neutrophil-lymphocyte ratio, platelet-lymphocyte ratio, and lactate dehydrogenase, were performed. The optimal cutoff points were determined by the Youden index. Logistic regression analyses for achieving objective responses to EV treatment were performed among these indicators. RESULTS: The median age of the cohort was 74 years, and the median follow-up duration was 10 months for the entire group. Median overall survival and progression-free survival from the initiation of EV were 12 and 6 months, respectively. The objective response rate and disease control rate were 48% and 70%, respectively. The receiver operating characteristic curve analysis aimed at predicting the achievement of an objective response to EV showed that the concordant index for the CAR was 0.774, significantly surpassing other indicators such as hemoglobin level, neutrophil-lymphocyte ratio, platelet-lymphocyte ratio, and serum lactate dehydrogenase. The Youden index identified an optimal cutoff value of 1 for CAR (mg/L for C-reactive protein and g/dL for serum albumin level) in predicting the objective response to EV treatment. Using the cutoff value for the CAR, the cohort was divided into 32 patients (29%) with lower CAR and 77 patients (71%) with higher CAR. The objective response rate was observed to be 84% in the lower CAR group and 32% in the higher CAR group (p < 0.0001). A logistic regression analysis revealed that an Eastern Cooperative Oncology Group Performance Status ≥1 (p = 0.04) and a CAR ≥1 (p < 0.001) were identified as independent predictors for the objective response to EV. CONCLUSIONS: The evaluation of the CAR from a concise blood examination at the initiation of EV could effectively predict the treatment response to EV in patients with metastatic urothelial carcinoma after the progression of platinum-based chemotherapy and checkpoint inhibitors.

Enfortumab vedotin, an antibody-drug conjugate that targets Nectin-4, is currently used for patients with metastatic urothelial carcinoma who no longer respond to checkpoint inhibitors. In the present report, we investigated which clinical indicators can predict achieving an objective response to enfortumab vedotin at the initiation of treatment. Among the blood-based putative indicators, the C-reactive protein-albumin ratio showed the highest value for predicting the treatment response to enfortumab vedotin. As the C-reactive protein-albumin ratio can be easily assessed from blood tests, physicians can consider evaluating it at the start of the EV treatment.

Durable Response to Enfortumab Vedotin Compared to Re-challenging Chemotherapy in Metastatic Urothelial Carcinoma After Checkpoint Inhibitors.

BACKGROUND: Enfortumab vedotin (EV), an antibody-drug conjugate targeting Nectin-4, has been used for patients with metastatic urothelial carcinoma (mUC) after progressing on checkpoint inhibitors (CPIs). Re-challenging chemotherapy with platinum agents and continuing CPIs beyond progressive disease (PD) have often been chosen following PD on CPIs, and several studies indicate favorable treatment effects of re-challenging chemotherapy. There is little evidence for comparing EV and re-challenging chemotherapy in real-world clinical practice. OBJECTIVE: The aim was to reveal the real-world treatment outcomes of EV, re-challenging chemotherapy, and continuing CPIs beyond PD in mUC patients. PATIENTS AND METHODS: A multi-institutional dataset of 350 mUC patients treated with CPIs was utilized. Overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and duration of response (DOR) were evaluated to compare the treatment arms. RESULTS: One hundred and nine mUC patients were treated with EV with a median follow-up of 6.4 months. The ORR and disease control rate (DCR) were 48% and 70%, respectively. The OS from PD on pembrolizumab exhibited significant differences among the three groups, with a median OS of 8, 14, and 29 months in continuing pembrolizumab beyond PD, re-challenging chemotherapy, and EV, respectively. When comparing the survival outcomes from the initiation of the treatment, there is neither a difference in OS (p = 0.124), PFS (p = 0.936), nor ORR (p = 0.816) between EV and re-challenging chemotherapy. Notably, the DOR in patients who achieved an objective response was significantly longer in the EV group than the re-challenging chemotherapy group (a median of 11 and 5 months, p = 0.049). For OS, the difference was not statistically significant (27 and 11 months in EV and re-challenging chemotherapy, respectively: p = 0.05). CONCLUSIONS: A superior effect of EV on patient survival compared to re-challenging chemotherapy and continuing pembrolizumab beyond PD was observed in our real-world analysis, which is attributed to the durable DOR in EV treatment despite the similar ORR to re-challenging chemotherapy.

Enfortumab vedotin (EV) is an antibody­drug conjugate targeting Nectin-4 and is now utilized for patients with metastatic urothelial carcinoma following treatment with checkpoint inhibitors (CPIs). Until recently, repeating chemotherapy using platinum drugs or continuing CPIs were often the treatments used for these patients. In the present study, we reported real-world treatment outcomes, mainly focusing on EV and repeating chemotherapy. Although the objective responses to the treatments were comparable, the duration of response for patients responding to the treatment was significantly longer in patients treated with EV than in those repeating chemotherapy, resulting in extended survival time with EV treatment.

Predicting Objective Response of Pembrolizumab in Platinum-Refractory Urothelial Carcinoma Based on NLR Fluctuation and Liver Metastases.

BACKGROUND AND PURPOSE: It is well known that patients with objective response to pembrolizumab have a durable duration of response leading to favorable survival outcomes. We investigated the possibility of predicting the objective response with concise indicators obtained from daily clinical practice. Methods In our multi-institutional cohort, 220 platinum-refractory metastatic urothelial carcinomas (mUC) treated with pembrolizumab for at least six weeks with complete information of objective response were investigated. Results The median follow-up was 7.3 months, and 119 patients deceased during the follow-up. A multivariate logistic regression analysis exhibited two independent variables predicting the objective response, including the neutrophil-lymphocyte ratio (NLR) change at six weeks of treatment and liver metastasis. We proposed a risk group using these two indicators. Patients with no predictive indicators / one of those were assigned to favorable (42%) / intermittent (47%) risk groups. Patients with both indicators were assigned to poor risk (11%). Notably, the objective response rate was well delineated in 41%, 25%, and 0% for favorable, intermediate, and poor risk groups, respectively (p<0.001). Distinct overall survival (OS) between the risk groups was also confirmed with the median OS of 14.1, 11.7, and 4.2 months in favorable, intermediate, and poor risk groups, respectively. CONCLUSIONS: At the six weeks of the pembrolizumab treatment, our risk model predicts the objective response rate precisely. Notably, those classified as 'poor risk'-marked by liver metastasis and a heightened NLR-should be considered for alternative therapy with a different mode of action, highlighting a critical decision point in treatment optimization.