Seattle Genetics Announces FDA Regular Approval of Adcetris (Brentuximab Vedotin) for Classical Hodgkin Lymphoma Patients

Seattle Genetics has announced that FDA has approved Adcetris (brentuximab vedotin) for the treatment of patients with classical Hodgkin lymphoma (HL) at high risk of relapse or progression as post-autologous hematopoietic stem cell transplantation (auto-HSCT) consolidation.

The approval is based on a Phase III clinical trial called AETHERA that was designed to compare up to 16 cycles (approximately one year) of Adcetris therapy administered every 3 weeks following auto-HSCT to placebo. The primary endpoint was met with a significant improvement in median progression-free survival (PFS) of 42.9 months (95% CI: 30.4, 42.9) for patients who received Adcetris versus 24.1 months (95% CI: 11.5, not estimable) for patients who received placebo, an improvement of 18.8 months (hazard ratio=0.57 [95% CI: 0.40, 0.81]; p-value=0.001).

In addition, data from the AETHERA trial converted the US accelerated approval of the relapsed classical HL indication to regular approval. Adcetris is an antibody-drug conjugate (ADC) directed to CD30, which is expressed in classical HL and systemic anaplastic large cell lymphoma (sALCL), as well as other lymphoma subtypes. This is the third indication for Adcetris, which was granted accelerated FDA approval in August 2011 for two other indications: (1) treatment of Hodgkin lymphoma patients who fail autologous transplant or who fail at least two prior multi-agent chemotherapy regimens and are not autologous transplant candidates, and (2) treatment of systemic ALCL patients who fail at least one prior multi-agent chemotherapy regimen. The sALCL indication is approved under accelerated approval based on overall response rate. Continued approval for this indication may be contingent upon verification and description of clinical benefit in confirmatory trials.

Globally, there are more than 65,000 cases of HL diagnosed each year. Although frontline combination chemotherapy can result in durable responses, up to 30% of these patients fail frontline treatment. The standard for these patients is salvage therapy, followed by auto-HSCT; approximately half of all HL patients who undergo an auto-HSCT experience subsequent disease relapse.

“With this FDA approval, Adcetris is the first and only consolidation treatment option available to high risk classical HL patients who undergo a transplant to preserve their post-auto-HSCT remissions,” said Clay Siegall, President and CEO of Seattle Genetics. “This represents a meaningful advance for cancer patients and an important milestone for the Adcetris development program. Together with our three ongoing Phase III trials and more than 30 additional clinical trials, this approval supports our goal to broadly establish Adcetris as the foundation of therapy for classical HL and CD30-expressing malignancies.”

“The FDA approval of brentuximab vedotin for post-autologous hematopoietic transplantation consolidation treatment in classical HL patients with high risk of relapse or progression is a significant milestone for patients and physicians,” said Craig Moskowitz, lead investigator on the trial and Clinical Director, Division of Hematologic Oncology, Memorial Sloan Kettering Cancer Center. “Approximately half of all HL patients who undergo an autologous hematopoietic stem cell transplant will relapse, representing a significant need for additional treatment options to improve progression free survival.”