Rosenberg et al. summarized a phase I, dose escalation trial of enfortumab vedotin (EV) – an ADC conjugate (anti-NECTIN-4–MMAE) – in 155 heavily pretreated patients with solid tumors, including mostly metastatic urothelial carcinoma (mUC). The recommended phase II dose was 1.25mg/kg, dosed 3 times over a 28-day cycle. EV was generally well tolerated, resulting in mostly grade 1–2 AEs, particularly skin (Nectin-4 on-target, off-tumor) and neuropathy (tubulin inhibitor MMAE). In 112 mUC patients receiving 1.25mg/kg EV, ORR was 43% and OS was 12.3 months, and was independent of age, prior anti-PD-(L)1 treatment, and liver mets. Phase II and III trials are underway.
Contributed by Katherine Turner
PURPOSE: To assess the safety/tolerability and antitumor activity of enfortumab vedotin (EV), a novel investigational antibody-drug conjugate that delivers the microtubule-disrupting agent, monomethyl auristatin E, to cells that express Nectin-4. METHODS: EV-101 is a phase I dose escalation/expansion study that enrolled patients with Nectin-4-expressing solid tumors (eg, metastatic urothelial carcinoma [mUC]) who progressed on >/= 1 prior chemotherapy regimen and/or programmed death-1 receptor/programmed death ligand-1 [PD-(L)1] inhibitor, including a cohort of patients with mUC who received prior anti-PD-(L)1 therapy. Patients received escalating doses of EV up to 1.25 mg/kg on days 1, 8, and 15 of every 28-day cycle. Primary objectives were evaluation of safety/tolerability and pharmacokinetics; antitumor activity was a secondary objective. RESULTS: Enrolled patients with mUC (n = 155) were heavily pretreated, with 96% having prior platinum-based chemotherapy and 29% receiving >/= 3 lines of prior treatment. Maximum tolerated dose of EV was not established; however, the recommended phase II dose was identified as 1.25 mg/kg. Rash, peripheral neuropathy, fatigue, alopecia, and nausea were the most common treatment-related adverse events (TRAEs); the most common TRAEs were grade 1-2 in severity. Among the 112 patients with mUC treated with single-agent EV 1.25 mg/kg, the investigator-assessed confirmed objective response rate (ORR) was 43%, and duration of response was 7.4 months. Median overall survival (OS) was 12.3 months, and the OS rate at 1 year was 51.8%. Similar ORR and estimated median OS were observed in patients >/= 75 years of age with and without prior anti-PD-(L)1 treatment, liver metastases, or upper-tract disease. CONCLUSION: Single-agent EV was generally well tolerated and provided clinically meaningful and durable responses in patients with mUC; survival data are encouraging. A pivotal phase II and a confirmatory phase III study are ongoing.
Author Info: (1) Memorial Sloan Kettering Cancer Center, New York, NY. (2) Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada. (3) H. Lee Moffitt Cancer Center
Author Info: (1) Memorial Sloan Kettering Cancer Center, New York, NY. (2) Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada. (3) H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL. (4) University of Michigan, Ann Arbor, MI. (5) Tom Baker Cancer Centre, Calgary, Alberta, Canada. (6) University of Colorado Comprehensive Cancer Center, Aurora, CO. (7) University of Kansas Cancer Center, Fairway, KS. (8) University of Wisconsin Carbone Cancer Center, Madison, WI. (9) Fox Chase Cancer Center, Philadelphia, PA. (10) Cross Cancer Institute, Edmonton, Alberta, Canada. (11) Barbara Ann Karmanos Cancer Institute, Wayne State University, Detroit, MI. (12) University of Miami, Miami, FL. (13) University of Southern California Norris Comprehensive Cancer Center, Los Angeles, CA. (14) Stanford University, Stanford, CA. (15) UNC Lineberger Comprehensive Cancer Center, Chapel Hill, NC. (16) Astellas Pharma, Northbrook, IL. (17) Seattle Genetics, Bothell, WA. (18) Astellas Pharma, Northbrook, IL. (19) Astellas Pharma, Northbrook, IL. (20) Yale School of Medicine, New Haven, CT.
