AstraZeneca (AZ) has shared promising results from a late-stage study of its immunotherapy Imfinzi (durvalumab) in non-muscle-invasive bladder cancer (NMIBC).
The phase 3 POTOMAC trial has been evaluating the drug in combination with standard-of-care (SOC) Bacillus Calmette-Guérin (BCG) induction and maintenance therapy in patients with high-risk NMIBC who have undergone transurethral resection of a bladder tumour (TURBT).
After one year, treatment with the Imfinzi regimen demonstrated a statistically significant and clinically meaningful improvement in disease-free survival (DFS) compared to BCG induction and maintenance therapy alone.
The safety and tolerability of the combination was also shown to be consistent with the known safety profiles of each individual medicine, and adding Imfinzi to SOC did not compromise patients’ ability to complete BCG induction and maintenance therapy.
A second arm assessing Imfinzi in combination with BCG induction-only therapy compared to BCG induction and maintenance therapy alone did not achieve the DFS endpoint, AZ said.
Bladder cancer is the ninth most common cancer globally and NMIBC, in which the cancer cells are confined to the inner lining of the bladder, accounts for more than 70% of diagnoses. Approximately 50% of patients with NMIBC are classed as being high-risk for disease progression or recurrence due to certain characteristics of their cancer.
AZ’s Imfinzi is designed to target the PD-L1 protein, which cancer cells use to evade the immune system. The drug was approved in the US at the end of March this year as part of a perioperative treatment regimen for adults with muscle-invasive bladder cancer (MIBC), named for its growth into the muscle wall of the bladder.
The approval in MIBC was based on positive results from the phase 3 NIAGARA trial, in which the Imfinzi regimen demonstrated a 32% reduction in the risk of disease progression, recurrence, not undergoing surgery, or death compared to neoadjuvant chemotherapy before radical cystectomy.
Cristian Massacesi, chief medical officer and oncology chief development officer at AZ, said the latest results for the therapy “represent a significant advance that will potentially allow more patients with early-stage bladder cancer to benefit from this important immunotherapy”.
Data from POTOMAC will be presented at a forthcoming medical meeting and shared with global regulatory authorities, according to the company.
Beyond bladder cancer, Imfinzi holds approvals to treat certain cases of lung cancer, biliary tract cancer, endometrial cancer and hepatocellular carcinoma.