Padcev, a first-in-class antibody-drug conjugate (ADC) that is directed against Nectin-4 protein, has secured approval under the FDA’s Accelerated Approval Program based on tumour response rate.
Nectin-4, which is located on the surface of cells, is mostly expressed in bladder cancer.
Urothelial cancer represents 90% of all bladder cancers and can also be found in the renal pelvis, ureter and urethra.
Astellas oncology therapeutic area head and senior vice president Dr Andrew Krivoshik said: “This approval underscores our commitment to develop novel medicines that address unmet patient needs, and we’re grateful to the patients and physicians whose participation led to this outcome.”
Padcev is intended for the treatment of adult patients with locally advanced or metastatic urothelial cancer who have earlier received a PD-1/L1 inhibitor and a platinum-containing chemotherapy before (neoadjuvant) or after (adjuvant) surgery or in a locally advanced or metastatic setting.
Padcev was evaluated in EV-201 single-arm and phase 2 multi-centre trial, which enrolled 125 patients with locally advanced or metastatic urothelial cancer.
According to Astellas, the primary endpoint of confirmed objective response rate (ORR) was 44% per blinded independent central review in the trial.
When treated with single-agent Padcev in the trial, 12% of patients exhibited a complete response, which implies no cancer could be identified at the time of evaluation. The 32% of patients exhibited a partial response in the study, thereby indicating a decrease in tumour size or extent of cancer in the body.
The median duration of response (DoR) was 7.6 months. It is a secondary endpoint in the study.
Nonclinical data indicated that Padcev’s anticancer activity is a result of its binding to Nectin-4 expressing cells followed by the internalisation and release of the anti-tumour agent monomethyl auristatin E (MMAE) into the cell, helping to restrict cell not reproducing and programmed cell death.
Seattle Genetics chief medical officer Dr Roger Dansey said: “PADCEV is the first antibody-drug conjugate approved for patients facing this aggressive disease, and it is the culmination of years of innovative work on this technology.”
Earlier this month, Astellas Pharma agreed to acquire AAV-based genetic medicines company Audentes Therapeutics for a total equity value of around $3bn.