The gang's all here: Merck's Keytruda nabs I-O's third bladder cancer approval this month

The FDA has approved an immuno-oncology med as a new treatment for bladder cancer—for the third week in a row. Only this one already has positive overall survival data under its belt.

Late Thursday, the FDA handed a pair of thumbs ups to Merck’s Keytruda in urothelial carcinoma—a second-line approval for certain patients with advanced or metastatic cancer, and a first-line accelerated approval that may depend on the company coming up with an overall survival benefit in ongoing trials. The go-aheads mean that each of the five checkpoint meds that bear one or more FDA approvals is now vying in the bladder cancer space.

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Merck, which was the first company ever to score a checkpoint nod when Keytruda won its melanoma OK, wasn’t necessarily expecting to arrive this late to the party. But May approvals for AstraZeneca’s Imfinzi—its first in any cancer—and Pfizer and Merck KGaA’s Bavencio pushed the New Jersey drugmaker to the back of the line.

RELATED: Roche’s shocking Tecentriq fail raises red flag for bladder cancer rivals

That doesn’t mean Merck can’t make a splash in the market, though, especially considering the recent Roche trial flop that put the fate of Keytruda’s competitors up in the air. Last week, the Swiss drugmaker said its Tecentriq—the first I-O med to arrive on the bladder cancer scene, which it did on the back of durable response data—failed to prove it could actually extend patients’ lives. The misstep puts Tecentriq’s approval in jeopardy, and it also puts pressure on BMS, AZ and the Pfizer/Merck KGaA pair to come up with their own positive overall survival results.

RELATED: Merck ends Keytruda trial early with data to challenge Opdivo in bladder cancer

Merck, though, has already done that in the second-line setting. Last October, the company announced that its second-line study had hit its primary endpoint and halted early, and earlier this week, its ASCO abstract for the trial—dubbed Keynote-045—showed Keytruda had extended overall survival by 10.3 months compared with chemo’s 7.4 months.

Meanwhile, most of Keytruda’s rivals don’t have much of an early-mover advantage. Bristol-Myers’ Opdivo won its blessing in February, meaning three of Keytruda’s four competitors have been in bladder cancer for less than four months.