Seattle Genetics, Astellas' bladder cancer med Padcev blows early expectations out of the water

Even a pandemic can’t slow Seattle Genetics and Astellas' new bladder cancer treatment Padcev down—and analysts are jacking up their sales estimates for the drug as a result.

In its first quarter on the market after a mid-December FDA approval, the therapy “blew out expectations … exceeding consensus estimates" by four- to fivefold with $34.5 million in sales, J.P. Morgan analyst Cory Kasimov wrote in a note to clients.

Even SVB Leerink’s Andrew Berens, whose Padcev sales projection was twice as high as Kasimov's, noted that the drug “handily beat our estimate of $10 million for the quarter, even in the midst of the pandemic.”

And the performance was no fluke, either. While other drugmakers have seen their Q1 sales boosted by some stockpiling early in the pandemic, that’s likely not what happened to Padcev, which “follows a ‘just in time’ delivery model” that sees the drug delivered as-needed, Kasimov wrote.

RELATED: Seattle Genetics, Astellas snag quick FDA approval for bladder cancer fighter Padcev

Berens also cited assurances from SeaGen’s leaders that many of the patients who received Padcev in Q1 are still alive and receiving therapy. Management said it “had no reason to believe this early adoption was driven primarily by a warehouse of end-stage patients which might have truncated duration of usage as has been seen with several other oncology drug launches.”

If that’s the case, “many of these Q1 patients are likely to be on the drug in Q2 given the expected duration of treatment of about 4.5 months in this setting,” Berens wrote, upping his 2020 target for the drug to $221 million and peak sales prediction in relapsed or refractory bladder cancer to $2 billion.

The thing is, SeaGen and Astellas aren’t stopping there. They're currently trying for a nod in previously untreated patients, an opportunity Berens pegs at $5.8 billion. And those SVB Leerink estimates don’t even factor in potential revenue from earlier stages of the disease, such as muscle-invasive bladder cancer (MIBC), a “sizable” market the companies are pursuing with a phase 3 trial testing Padcev alongside Merck immuno-oncology powerhouse Keytruda.

“We estimate there are about 10,000 MIBC patients in the U.S., and the expected duration of therapy could be significant in these less advanced patients,” Berens wrote.

But it wasn’t all rosy news for Seattle Genetics in Q1, with Adcetris—until December its only approved drug, and a powerhouse with several indications—narrowly missing consensus estimates at $164.1 million.