Durvalumab Granted FDA Priority Review for Muscle-Invasive Bladder Cancer Patients

Durvalumab has received Priority Review from the US Food and Drug Administration (FDA) for muscle-invasive bladder cancer (MIBC). Backed by positive NIAGARA Phase III trial results, it significantly reduces disease recurrence and improves survival. If approved, Durvalumab (Imfinzi) would be the first perioperative immunotherapy in this setting, offering new hope for patients with limited treatment options.

Developed by AstraZeneca, Durvalumab perioperative regimen reduced the risk of death by 25% versus standard treatment. At two years, 82.2% of patients on Imfinzi survived compared to 75.2% in the comparator group, with median survival not yet reached.

The FDA’s Priority Review status is reserved for therapies that offer significant advancements in safety, efficacy, or patient outcomes. The regulatory decision, expected in the second quarter of 2025, could position Durvalumab as the first and only perioperative immunotherapy regimen for MIBC in a curative-intent setting.

Susan Galbraith, Executive Vice President of Oncology R&D at AstraZeneca, emphasized the significance of this breakthrough. “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. Today’s 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 NIAGARA Trial: Promising Results

The FDA’s decision is supported by compelling data from the NIAGARA Phase III trial, which was highlighted at the 2024 European Society for Medical Oncology (ESMO) Congress and published in The New England Journal of Medicine.

The trial evaluated the efficacy of Durvalumab combined with neoadjuvant chemotherapy followed by adjuvant Durvalumab monotherapy against the standard regimen of neoadjuvant chemotherapy and radical cystectomy. The results showed:

• Event-Free Survival (EFS): Durvalumab reduced the risk of disease progression, recurrence, inability to undergo surgery, or death by 32% (hazard ratio [HR]: 0.68; 95% confidence interval [CI]: 0.56-0.82; p<0.0001). At two years, 67.8% of patients in the Durvalumab arm remained event-free compared to 59.8% in the standard treatment group.
• Overall Survival (OS): Durvalumab showed a 25% reduction in the risk of death (HR: 0.75; 95% CI: 0.59-0.93; p=0.0106), with an estimated two-year survival rate of 82.2% versus 75.2% for the comparator arm.

Safety and Tolerability

Durvalumab demonstrated a favorable safety profile in the trial, with no unexpected adverse effects. Importantly, its addition to neoadjuvant chemotherapy did not compromise the ability of patients to complete their chemotherapy cycles or undergo surgery.

Global Implications

In addition to the US, regulatory applications for Durvalumab are under review in the EU, Japan, and several other countries. If approved, this innovation could establish a new benchmark for treating MIBC, offering hope to thousands of patients worldwide.

Muscle-Invasive Bladder Cancer

MIBC affects approximately 25% of bladder cancer patients and is characterized by the tumor invading the muscle wall of the bladder, though without distant metastases. Current standard care includes neoadjuvant chemotherapy followed by radical cystectomy (bladder removal). However, recurrence remains a significant challenge, with nearly half of patients experiencing cancer progression despite aggressive treatment.