AZ withdraws Imfinzi in US bladder cancer use after trial failure

AstraZeneca has suffered a setback after it voluntarily withdrew its cancer immunotherapy Imfinzi (durvalumab) in a bladder cancer indication in the US.

AZ's share price ticked downwards after the announcement that it will stop marketing Imfinzi, a PD-L1 class immunotherapy, for previously treated adult patients with advanced or metastatic bladder cancer.

It’s news that will likely hand market share to Roche and Pfizer/Merck KGaA, whose respective immunotherapies Tecentriq and Bavencio have bladder cancer indications.

In a statement, the big UK pharma said it had made the decision in consultation with the FDA, which was running the rule over results from the phase 3 DANUBE trial.

Following an accelerated approval in 2017 based on earlier clinical data DANUBE was supposed to supply the confirmatory survival data for Imfinzi’s first line bladder cancer indication.

But in March last year AZ announced that DANUBE had failed to meet its overall survival endpoints compared with standard care in advanced bladder cancer patients with high levels of the PD-1 biomarker, or patients regardless of their PD-1 status.

The trial tested Imfinzi as monotherapy and as part of a combination with AZ’s CTLA-4 immunotherapy and neither showed an improvement over standard care.

AZ said that the withdrawal is aligned with FDA post-approval guidance, where trial data did not meet post-approval requirements.

The news will come as a blow for AZ, where Imfinzi has been an important component of the company’s cancer portfolio.

In full year 2020 results the drug generated over $2 billion, with US sales of just under $1.2 billion.

AZ did not provide sales by indication but Imfinzi is also approved in unresectable stage III non-small cell lung cancer after chemoradiation therapy in the US and other markets, based on data from the PACIFIC phase 3 trial.

It is also approved in extensive stage small cell cancer in the US and other markets based on findings from the CASPIAN phase 3 trial.

It is also being tested in a range of other cancers, including in combination with tremelimumab, liver cancer, biliary tract cancer, oesophageal cancer, ovarian cancer and other solid tumours.