Seattle Genetics scores Adcetris expansion for 'high risk' lymphoma patients

Seattle Genetics ($SGEN) just won a boost for its lymphoma drug Adcetris. The FDA added a new indication to the drug's toolbox, for patients with Hodgkin's lymphoma at high risk of relapse after a stem-cell transplant.

Seattle Genetics CEO Clay Siegall

Already approved for Hodgkin's lymphoma patients who've relapsed after a stem-cell transplant or after two other chemo cocktails, and patients with systemic anaplastic large cell lymphoma (sALCL), Adcetris gains access to a bigger market with the new approval. Up to 30% of Hodgkin's lymphoma patients fail on initial treatments, the company said in a release, and half of patients relapse after a stem cell transplant.

Adcetris is now the only drug FDA-approved to keep HL patients in remission after a stem cell transplant, CEO Clay Siegall said in a statement. The drug also got more FDA backing, with the agency converting its accelerated approval to full approval.

The new indication is based on a late-stage trial in 329 patients, in which Adcetris staved off cancer progression for almost two years longer than placebo. Published in The Lancet earlier this year, the trial showed median progression-free survival in the Adcetris arm of 43 months, compared with 24 months in the placebo group.

It's "a significant milestone for patients and physicians," lead investigator Craig Moskowitz of Memorial Sloan Kettering Cancer Center said in a statement. The fact that half of stem-cell transplant patients relapse shows "a significant need for additional treatment options to improve progression-free survival," he added.

Analysts figure the new use can not only boost uptake, but potentially keep patients on therapy for a longer period of time, giving an added sales boost. Plus, the updated label appears to give physicians some leeway in deciding which patients qualify as "high risk"--and thus for Adcetris, Leerink Partners' Seamus Fernandez pointed out. "This could potentially allow for a broader interpretation by prescribing oncologists as to which patients would be appropriate for Adcetris use in this setting," Fernandez said in a Tuesday note.

Seattle Genetics has been on a partnering binge, both with bigger companies that want access to its cancer candidates and smaller firms whose early-stage work Seattle Genetics finds promising. Both Bayer and AbbVie ($ABBV) have pledged big money to collaborate on antibody drug conjugates (ADCs), with $520 million and $255 million deals, respectively. Most recently, Seattle Genetics agreed to a $645 million immuno-oncology deal with Unum Therapeutics, aiming to put its ADC technology to work with Unum's next-gen T-cell efforts. In April, the company announced it would recruit 100 new workers to accelerate its armed-antibody drug candidates through the pipeline.

- read the Seattle Genetics release

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