698P Analysis of hard-to-treat subgroups from EV-301: A phase III trial of enfortumab vedotin (EV) vs chemotherapy for previously treated advanced urothelial carcinoma

Enfortumab vedotin in the treatment of urothelial cancers and beyond

Enfortumab vedotin (EV) is the first antibody-drug conjugate approved for locally advanced or metastatic urothelial cancers (la/mUCs), a disease group historically associated with limited prognosis and therapeutic options. EV consists of monomethyl auristatin E, a microtubule-disrupting agent linked to an antibody targeting Nectin-4. In clinical trials, EV demonstrated high response rates and superior survival in the third-line setting for la/mUC compared with chemotherapy. Peripheral neuropathy and rash were among the most common serious adverse events. EV is currently approved in multiple countries for the treatment of la/mUC in the later-line setting. Ongoing trials seek to expand the indication for EV and to study therapeutic combinations with other agents.

Antibody-Drug Conjugates in Uro-Oncology

Currently available treatment options for patients with refractory metastatic prostate, bladder, or kidney cancers are limited with the prognosis remaining poor. Advances in the pathobiology of tumors has led to the discovery of cancer antigens that may be used as the target for cancer treatment. Antibody-drug conjugates (ADCs) are a relatively new concept in cancer treatment that broaden therapeutic landscape. ADCs are examples of a 'drug delivery into the tumor' system composed of an antigen-directed antibody linked to a cytotoxic drug that may release cytotoxic components after binding to the antigen located on the surface of tumor cells. The clinical properties of drugs are influenced by every component of ADCs. Regarding uro-oncology, enfortumab vedotin (EV) and sacituzumab govitecan (SG) are currently registered for patients with locally advanced or metastatic urothelial cancer following previous treatment with an immune checkpoint inhibitor (iCPI; programmed death receptor-1 [PD-1] or programmed death-ligand 1 [PD-L1]) inhibitor) and platinum-containing chemotherapy. The EV-301 trial showed that EV significantly prolonged the overall survival compared with classic chemotherapy. The TROPHY-U-01 trial conducted to evaluate SG demonstrated promising results as regards the objective response rate and duration of response. The safety and efficacy of ADCs in monotherapy and polytherapy (mainly with iCPIs) for different cancer stages and tumor types are assessed in numerous ongoing clinical trials. The aim of this review is to present new molecular biomarkers, specific mechanisms of action, and ongoing clinical trials of ADCs in genitourinary cancers. In the expert discussion, we assess the place of ADCs in uro-oncology and discuss their clinical value.