ASH: Seagen aims to win over Adcetris holdouts with key 5-year lymphoma data

Adcetris
Seagen's Adcetris was the company's first marketed product. It's now joined by fellow cancer meds Tukysa and Padcev. (Seagen)

It’s something Seagen has known since it was testing Adcetris in phase 1 studies years ago: Doctors who treat Hodgkin lymphoma look to five-year data to make their treatment decisions.

“They like the approval and all that,” but seeing five-year disease-free survival data, “which is what they consider their definition of a cure… doctors look at that as an important milestone,” CEO Clay Siegall said.

Now, Seagen and partner Takeda have exactly that. Monday at the American Society of Hematology (ASH) virtual annual meeting, they presented data showing that at the five-year mark, Adcetris—in combination with chemo drugs adriamycin, vinblastine and dacarbazine (AVD)—cut previously untreated classical Hodgkin lymphoma patients’ risk of disease worsening or death by 32% compared with a regimen of AVD plus fellow chemotherapy bleomycin.

In the Adcetris arm of the study, which looked at patients with stage 3 and stage 4 Hodgkin lymphoma, 82.2% of patients made it five years without their cancer progressing, compared with 75.3% of those in the ABVD group.

Adcetris treatment was also associated with fewer secondary malignancies, “quite a number” of which have historically popped up in patients on the four-drug standard-of-care cocktail, Siegall said. Of 48 trial patients with recorded secondary malignancies—spanning both hematological and solid tumors—19 were in the Adcetris arm, versus 29 in the ABVD arm.

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While Adcetris has “pretty good market penetration already” after a number of years on the market, Seagen is still hoping for—and expecting— a commercial boost on the back of the new data.

“I certainly could see some additional doctors who just were waiting for a five-year time point say, ‘This makes sense,’” Siegall said.

And while the company isn’t nearly as dependent on Adcetris revenues as it was not too long ago—thanks to blockbuster nods in the past year for bladder cancer treatment Padcev and breast cancer drug Tukysa—it could still use a boost in the sales department.

A top-line miss for Seagen in the third quarter, coupled with a cut to its guidance, “could place more of a focus on efforts to increase penetration in early lines of Hodgkin lymphoma,” SVB Leerink analyst Andrew Berens wrote in a note to clients last week.

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Siegall, though, expects to see revenues pick up again; he attributed the slip to patients staying away from hospitals on account of the COVID-19 pandemic. Eventually, "they're going to need to come in and get their cancer therapy, and I think it’s best for them to do that,” he said.

“At some point—and we see a light at the end of the tunnel with these vaccines—we’ll get back to treating a more normal amount of Hodgkin lymphoma patients so that they aren’t just at home progressing with their disease,” he said.