Seagen, Astellas eye earlier Padcev use in bladder cancer with long-lasting phase 2 results

Padcev
Seagen and Astellas Padcev won its third-line OK last December. (Seagen)(Seattle Genetics)

Right now, Seagen and Astellas’ Padcev is cleared only for metastatic bladder cancer patients who have already received chemo and a checkpoint inhibitor from the PD-1/PD-L1 class. But thanks to new findings, the drug may be headed for an OK earlier in treatment.

Monday, the pair revealed that their antibody-drug conjugate produced long-lasting responses in patients who had received immunotherapy but were ineligible for cisplatin chemo. The drug spurred a response in 52% of patients, with patients experiencing benefits for a median 10.9 months.

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

The companies plan to release more details at an upcoming scientific congress. But in the meantime, they’ll be discussing them with regulators. And while the study they come from is a single-arm phase 2, the data “may support a regulatory application” to extend Padcev’s use in the U.S., Roger Dansey, M.D., Seagen’s chief medical officer, said in a statement.

It wouldn’t be the first time data from the trial, dubbed EV-201, earned them a nod. The FDA in December cleared Padcev in third-line patients who had received both chemo and a checkpoint inhibitor based on data from a different cohort of the study, which showed the drug could shrink tumors in 44% of patients and eliminate them in 12%.

But even without the FDA go-ahead, doctors are already using Padcev in the second-line setting—and without payer pushback, SVB Leerink analyst Andrew Berens wrote in a note to clients.

RELATED: ASCO: Astellas, Seattle Genetics' ADC banishes 12% of bladder cancers

Meanwhile, industry watchers are already looking ahead to what Padcev may do in newly diagnosed, chemo-eligible patients. With second-line patients responding for a median 10.9 months—considerably longer than the third-line population’s median duration of response, which checked in at 7.6 months—"we believe that the duration in the healthier frontline patients able to receive cisplatin will be similarly prolonged,” Berens wrote.

With all these factors in mind, he and his colleagues now expect to see Padcev bring in about $3.5 billion in peak sales—almost double the $1.9 billion they previously forecast, he noted.