AstraZeneca eyes less-frequent Imfinzi dosing with FDA 'priority' boost

AstraZeneca's Imfinzi is currently dosed every two weeks in Stage 3 NSCLC and bladder cancer. (AstraZeneca)

Right now, AstraZeneca's Imfinzi lags behind some of its key competitors in the PD-1/PD-L1 class when it comes to convenience, requiring more frequent dosing than Bristol Myers Squibb's Opdivo, Roche's Tecentriq and Merck’s Keytruda in certain indications. But the British drugmaker doesn’t intend to let stay that way for long.

The FDA Tuesday handed AZ a priority review for a new four-week dosing regimen for blockbuster Imfinzi in Stage 3 non-small cell lung cancer and bladder cancer. The company is expecting a verdict from regulators in the fourth quarter, it said.

RELATED: Merck grabs FDA green light for less-frequent Keytruda dosing regimen

If AZ can snag a green light for the new dosing schedule, it would cut patient visits to treatment centers by half. Currently, Imfinzi patients receive the drug every two weeks at a weight-based dose in those two indications. Reducing those visits would not only up Imfinzi’s convenience factor and free up treatment center resources, but keep vulnerable patients home amid the COVID-19 pandemic, too.

A new nod could also help the drug hang with its competition. While bladder cancer is a smaller arena, it’s also immuno-oncology’s most crowded: Five drugmakers in the class bear approvals for their contenders. One of them is Merck's Keytruda, which in April nabbed its own long-acting nod for use every six weeks. But clearance for use every four weeks would still lift Imfinzi within the bladder cancer pack, tying it with BMS' Opdivo and Roche's Tecentriq, each of which boasts its own every-four-weeks OK.

The much larger revenue driver for Imfinzi is its indication in Stage 3 NSCLC post-chemo and radiation therapy; that approval has helped the drug reach blockbuster heights, with $492 million in sales last quarter alone. Right now, in-class competition isn’t imminent, but the new dosing flexibility will only raise the bar for AstraZeneca’s future competitors.

RELATED: AstraZeneca's Imfinzi gets FDA green light to challenge Roche in small cell lung cancer

Meanwhile, the new fixed-1,500mg dose is already in use in small cell lung cancer, a field where AstraZeneca scored an FDA go-ahead this March. Results from the company’s pivotal small-cell trial in that field, dubbed Caspian, helped form the basis for Tuesday’s priority review designation.

Editor's note: This story has been corrected to reflect the fact that BMS' Opdivo, not Merck's Keytruda, was the first member of its class to win FDA approval for less-frequent dosing. Roche's Tecentriq is also approved for use every four weeks.