Bristol-Myers Squibb's immunotherapy Opdivo has taken big step towards European approval in bladder cancer, after regulators validated the firm's application, kick-starting the European Medicines Agency's centralised review process.

The company has filed to extend the drug's list of indications to include the treatment of locally advanced unresectable or metastatic urothelial carcinoma (mUC) in adults after failure of prior platinum-containing therapy.

The application primarily included data from CheckMate-275, a Phase II, open-label, single-arm study assessing the safety and efficacy of Opdivo (nivolumab) in patients with locally advanced unresectable or mUC that has progressed after a platinum-containing therapy; data presented at American Society of Clinical Oncology meeting earlier this year showed an objective response rate of 24.4 percent.

Bladder cancer is the fifth most common cancer in Europe, with an estimated 151,000 new cases diagnosed per year and over 52,000 deaths per year. Urothelial carcinoma is the most common type, accounting for around 90 percent of cases.

"The high frequency of metastatic urothelial carcinoma and its relapsing nature highlight the substantial need for new treatment approaches with high and durable responses," said Fouad Namouni, BMS' head of development in Oncology.

Opdivo is a PD-1 immune checkpoint inhibitor, already approved in Europe for the treatment of advanced melanoma, metastatic squamous and non-squamous non-small cell lung cancer, kidney cancer and previously-treated recurrent or metastatic squamous cell carcinoma of the head and neck.