Astellas Pharma and Seattle Genetics have started dosing in the Phase Ib EV-103 clinical trial of enfortumab vedotin combined with pembrolizumab or atezolizumab as first or second line treatment of locally advanced or metastatic urothelial cancer.
Enfortumab vedotin is an antibody-drug conjugate (ADC) being developed to target Nectin-4 with the delivery of cell-killing agent monomethyl auristatin E (MMAE).
The drug candidate comprises an anti-Nectin-4 monoclonal antibody linked with the MMAE.
Pembrolizumab and atezolizumab are different types of immune checkpoint inhibitors (CPI).
The single arm, open label, multi-centre Phase Ib trial will involve administration of enfortumab vedotin for one and two weeks of every three-week cycle. Pembrolizumab or atezolizumab will be given during week one of the cycle.
EV-103 will evaluate the investigational candidate in up to 85 patients ineligible for first line cisplatin-based chemotherapy or have progressed after a regimen, including platinum-based chemotherapy.
Astellas Pharma oncology development senior vice-president and global therapeutic area head Steven Benne said: "Many patients do not respond to or relapse after treatment with CPIs, and we are committed to exploring additional ways to potentially address the unmet needs of the urothelial cancer community."
The primary objective of the trial is the safety and tolerability of enfortumab vedotin in combination with the CPI treatment.
During the trial, secondary endpoints such as recommended dose in combination with CPIs, overall response rate (ORR), duration of response (DOR), progression-free survival (PFS) and overall survival (OS) will also be monitored.
Enfortumab vedotin is being further assessed as a monotherapy in the EV-201 trial for advanced urothelial cancer.