This decision was made in consultation with the Food and Drug Administration (FDA).
Imfinzi (durvalumab) is a human monoclonal antibody that is designed to bind to PD-L1 and blocks the interaction of PD-L1 with PD-1 and CD80, countering the tumor's immune-evading tactics and releasing the inhibition of immune responses.
Revenues from Imfinzi grew 42% to $1.48bn in the first nine months of 2020, the company reported.
The drug was granted accelerated approval for the bladder cancer indication in 2017.
Continued approval was contingent on results from the DANUBE Phase III trial in the 1st-line metastatic bladder cancer setting, which did not meet its primary endpoints in 2020, said the company.
Dave Fredrickson, executive vice president, oncology business unit, AstraZeneca, said: “The science of immunotherapy has moved swiftly over the past few years, bringing new options to patients at an unprecedented pace. While the withdrawal in previously treated metastatic bladder cancer is disappointing, we respect the principles FDA set out when the accelerated approval pathway was founded and remain committed to bringing new and innovative options to patients.”
This withdrawal does not impact the bladder cancer indication outside the US and does not impact other approved Imfinzi indications within or outside the US, said the Anglo-Swedish pharma giant.
Head and neck cancer
Earlier this month, the company also announced that Imfinzi did not prolong survival in a trial testing it as an initial treatment of head and neck cancer.
“Metastatic head and neck cancer is a complex and challenging disease with a poor prognosis. While we are disappointed by these results, insights from the KESTREL Phase III trial will advance our understanding and application of immunotherapy across our clinical development program,” said Fredrickson at the time.
Lung cancer focus
However, the company stresses that, in the last three years, Imfinzi has become an important standard of care in multiple lung cancer settings. This is an area of “increasing focus” for AstraZeneca, said Fredrickson.
The checkpoint inhibitor is approved in the US, Japan, China, the EU, and many other markets, for the treatment of patients with stage III non-small cell lung cancer (NSCLC) whose cancer is unresectable and has not progressed after chemoradiation based on results from the PACIFIC Phase III trial. It is also approved in the EU, US, Japan, and other markets for the treatment of extensive stage small cell lung cancer (ES-SCLC) based on the CASPIAN Phase III trial.
As part of a broad development program, Imfinzi is being tested as a monotherapy and in combinations including with tremelimumab, an anti-CTLA4 monoclonal antibody and potential new medicine, as a treatment for patients with NSCLC, SCLC, bladder cancer, liver cancer, biliary tract cancer, esophageal cancer, gastric and gastroesophageal cancer, cervical cancer, ovarian cancer, endometrial cancer, and other solid tumors.
