238P - Enfortumab-vedotin for metastatic urothelial carcinoma refractory to platinum-based chemotherapy and immune checkpoint inhibitors: A single institution experience

Background

The EV-301 trial showed the efficacy of Enfortumab-Vedotin (EV) in the 3rd-line therapy for metastatic Urothelial Carcinoma (mUC) previously treated with platinum-combined chemotherapy and immune-checkpoint inhibitor. Here we showed an initial report of EV in our institution.

Methods

25 patients (Pts) with mUC received EV from January 2021 to July 2023 at our institution. EV was administered 10mg/kg weekly until disease progression. Whole-body CT scan was performed every two months(Ms). We retrospectively evaluated progression free survival based on RECIST version 1.1 as efficacy and adverse events (AEs) rate based on the National Cancer Institute CTCAE, version 4.03 as safety.

Results

Of 25 patients (Pts), with median age of 73 (54-85), 16 (64%) Pts had bladder tumor, 9(36%) Pts had upper urinary tract, 1 Pt had both upper and lower urinary tract as primary. 18(72%) Pts had lymph node metastasis (Mets), 14(56%) Pts had lung Mets, 5 (20%) Pts had liver Mets 4 (16%) Pts had bone Mets. 5(20%) Pts had 4 regimens, 7(28%) Pts had 3 regimens and 13(52%) Pts had 2 regimens of pre-treated systemic therapy for mUC. During the median follow-up period of 7.0 (2.1-16.2) Months, 9 (36%) Pt had died. The best response during follow-up period was CR in2(8%), PR in 11(44%), SD in 11(44%) and PD in1(4%) Pts. Median PFS was 10.5 Ms and OS was 13.0. 8 Severe AEs (more than Grade3) was occurred in 8 (32%) Pts, derimatosis was the highest occurrence AE and 65% patients had ermatosis. OS of patiets with prior taxane therapy was significantly worse than that of patients without prior taxane therapy (11.4M vs 14.1M, p=0.027).

Conclusions

Initial report of Enfortumab-Vedotin resulted in a median PFS of 10.5 Ms and 20% severe AE, which was as safe and effective as the report from clinical trial. OS of patients pre-treated with taxane therapy was significantly worse than that of patients without prior taxane therapy.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.