AstraZeneca Imfinzi granted priority review by USFDA for muscle-invasive bladder cancer

The Food and Drug Administration (FDA) grants Priority Review to applications for medicines that, if approved, would offer significant improvements over available options by demonstrating safety or efficacy improvements, preventing serious conditions or enhancing patient compliance. The Prescription Drug User Fee Act date, the FDA action date for their regulatory decision, is anticipated during the second quarter of 2025.

Approximately one in four patients with bladder cancer has evidence of the tumour invading the muscle wall of the bladder (without distant metastases), known as MIBC. In MIBC, a curative-intent setting, approximately 117,000 patients are treated with current standard of care. Standard treatment includes neoadjuvant chemotherapy and radical cystectomy. However, even after cystectomy, patients experience high rates of disease recurrence and a poor prognosis.

Susan Galbraith, Executive Vice President, Oncology R&D, AstraZeneca, said, “New options for muscle-invasive bladder cancer are vital because nearly half of patients will see their cancer return or progress despite undergoing curative-intent treatment, including removal of their bladder. The Priority Review designation recognises the urgent need for new options for these patients and the potential of Imfinzi to transform the standard of care as the first and only perioperative immunotherapy regimen to delay recurrence and extend survival in this setting.”

The sBLA is based on data from the NIAGARA Phase III trial which was presented during a Presidential Symposium at the 2024 European Society for Medical Oncology (ESMO) Congress and simultaneously published in The New England Journal of Medicine.

In the trial, patients were treated with Imfinzi in combination with neoadjuvant chemotherapy before radical cystectomy followed by Imfinzi as adjuvant monotherapy, or neoadjuvant chemotherapy before radical cystectomy. In a planned interim analysis, perioperative Imfinzi demonstrated a 32% reduction in the risk of disease progression, recurrence, not undergoing surgery, or death versus neoadjuvant chemotherapy with radical cystectomy alone (based on event-free survival [EFS] hazard ratio [HR] of 0.68; 95% confidence interval [CI] 0.56-0.82; p<0.0001). Estimated median EFS was not yet reached for the Imfinzi arm versus 46.1 months for the comparator arm. An estimated 67.8% of patients treated with the Imfinzi regimen were event free at two years compared to 59.8% in the comparator arm.

Results from the key secondary endpoint of overall survival (OS) showed that the Imfinzi perioperative regimen reduced the risk of death by 25% versus neoadjuvant chemotherapy with radical cystectomy (based on OS HR of 0.75; 95% CI 0.59-0.93; p=0.0106). Median survival was not yet reached for either arm. An estimated 82.2% of patients treated with the Imfinzi regimen were alive at two years compared to 75.2% in the comparator arm.

Imfinzi was generally well tolerated, and no new safety signals were observed in the neoadjuvant and adjuvant settings. Further, adding Imfinzi to neoadjuvant chemotherapy was consistent with the known profiles of the individual agents and did not impact patients’ ability to complete four cycles of chemotherapy or undergo surgery compared to neoadjuvant chemotherapy alone.

Regulatory applications are currently under review in the EU, Japan and several other countries based on the NIAGARA results.