Imfinzi regimen boosts bladder cancer survival

Positive high-level results from the POTOMAC Phase III trial showed one year of treatment with AstraZeneca’s Imfinzi (durvalumab) plus standard-of-care BCG induction and maintenance therapy demonstrated a statistically significant and clinically meaningful improvement in disease-free survival (DFS) for patients with high-risk non-muscle-invasive bladder cancer (NMIBC) compared to BCG induction and maintenance therapy alone.​ The trial was not statistically powered to formally test overall survival (OS) however a descriptive analysis demonstrated no detriment.

More than 70% of bladder cancer patients are diagnosed with NMIBC, an early-stage cancer where the tumour is in the tissue that lines the inner surface of the bladder but has not invaded the muscle wall. About half of patients with NMIBC are classified as high-risk for disease progression or recurrence because of certain characteristics of their cancer, such as tumour grade, stage and specific tumour features.

Maria De Santis, MD, Head of the Interdisciplinary Uro-Oncology Section at Charité Universitätsmedizin Berlin, Germany, and a principal investigator in the POTOMAC trial, said: “These exciting data show that adding one year of durvalumab to the current standard treatment significantly extends the time patients live without high-risk disease recurrence or progression. While most patients with non-muscle invasive bladder cancer are treated with curative intent, 80 per cent see their disease return and almost half may require life-altering surgery to remove the bladder, underscoring the urgent need to improve treatment."

Cristian Massacesi, Chief Medical Officer and Oncology Chief Development Officer, AstraZeneca, said: “The positive results for Imfinzi in the POTOMAC trial represent a significant advance that will potentially allow more patients with early-stage bladder cancer to benefit from this important immunotherapy. Building on the NIAGARA data, this outcome demonstrates our strategy of bringing novel therapies to patients with early-stage disease where there is the greatest potential for long-term benefit.”

The safety and tolerability of Imfinzi plus BCG induction and maintenance therapy was consistent with the known safety profiles of the individual medicines, with no new safety concerns identified. The addition of Imfinzi did not compromise patients' ability to complete BCG induction and maintenance therapy. The second experimental arm evaluating Imfinzi plus BCG induction-only therapy compared to BCG induction and maintenance therapy alone did not meet the endpoint of DFS. These data will be presented at a forthcoming medical meeting and shared with global regulatory authorities.

Imfinzi is approved in the US and other countries for patients with muscle-invasive bladder cancer (MIBC) based on results from the NIAGARA Phase III trial and continues to be investigated across early and late-stage bladder cancer in various treatment combinations, including in patients with MIBC who are ineligible or refuse to take cisplatin (VOLGA) and in locally advanced or metastatic disease (NILE).

POTOMAC is a randomised, open-label, multi-centre, global Phase III trial evaluating Imfinzi in combination with BCG therapy as a treatment for 1,018 patients with high-risk, BCG-naïve NMIBC who have undergone TURBT prior to randomisation. Patients were randomised 1:1:1 to receive Imfinzi plus BCG induction and maintenance therapy, or Imfinzi plus BCG induction-only therapy, versus standard-of-care BCG induction and maintenance therapy. The trial was conducted in more than 120 centres across 12 countries including Canada and others across Europe and Asia. The primary endpoint was DFS, defined as time from randomisation to date of first recurrence of high-risk disease or death from any cause, for Imfinzi plus BCG induction and maintenance therapy compared to BCG induction and maintenance therapy alone. Secondary endpoints included DFS for Imfinzi plus BCG induction only therapy versus the comparator arm, as well as OS at five years and safety across both experimental arms of the trial.