Takeda Pharmaceutical Company Limited and Seagen Inc. announced that overall survival (OS) data from the Phase 3 ECHELON-1 clinical trial of an ADCETRIS® (brentuximab vedotin) plus chemotherapy combination will be presented in an oral session at the 59th American Society of Clinical Oncology (ASCO) Annual Meeting on June 3, 2022, 1:00-4:00 PM CT, and at the 27th European Hematology Association (EHA) Annual Meeting on June 10, 2022, 11:30 – 12:45 CEST. Data from the ECHELON-1 trial demonstrated a statistically significant improvement in OS in adult patients with previously untreated Stage III or IV classical Hodgkin lymphoma treated with ADCETRIS plus doxorubicin, vinblastine and dacarbazine (A+AVD) vs. doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD).

With approximately six years median follow up (73 months), patients receiving A+AVD had a 41% reduction in the risk of death (hazard ratio [HR] 0.59; 95% confidence interval [CI]: 0.396 to 0.879), with an estimated OS rate (95% CI) of 93.9% (91.6, 95.5) at 6 years. The safety profile of ADCETRIS was consistent with previous studies, and no new safety signals were observed. Please see Important Safety Information, including a SPECIAL/BOXED WARNING for progressive multifocal leukoencephalopathy (PML), for ADCETRIS below.

ADCETRIS is indicated for the treatment of adult patients with previously untreated Stage III or IV classical Hodgkin lymphoma in combination with AVD in the United States and for the treatment of adult patients with previously untreated CD30-positive Stage IV Hodgkin lymphoma in combination with AVD in Europe. First-line brentuximab vedotin plus chemotherapy to improve overall survival in patients with stage III/IV classical Hodgkin lymphoma: An updated analysis of ECHELON-1. (Hematologic Malignancies—Lymphoma and Chronic Lymphocytic Leukemia on Friday, June 3, 2022, 1:00 PM-4:00 PM CT at McCormick Place, Hall A8). Key findings, which will be presented by Dr. Ansell, include: The trial achieved its key secondary endpoint with the combination of A+AVD, resulting in a statistically significant improvement in OS versus the control arm of ABVD as assessed by an Independent Review Facility (IRF) (HR 0.59; p-value=0.009).

This corresponds to a 41% reduction in the risk of death. At a median follow up of 73 months, 39 and 64 OS events occurred in the A+AVD and ABVD arms, respectively. Estimated six-year OS rates (95% CI) were 93.9% (91.6, 95.5) with A+AVD vs.

89.4% (86.6, 91.7) with ABVD. Subgroup analyses supported a consistent benefit for A+AVD vs. ABVD.

The six-year PFS estimate (95% CI) was 82.3% (79.1, 85.0) with A+AVD vs. 74.5% (70.8, 77.7) with ABVD. A+AVD resulted in a manageable safety profile consistent with prior reports.

Treatment-emergent peripheral neuropathy continued to resolve or improve in both arms, with 86% (379/443) and 87% (249/286) of patients in the A+AVD and ABVD arms, respectively, either completely resolving (72% vs. 79%) or improving (14% vs. 8%) by last follow up.

Fewer patients reported second malignancies in the A+AVD vs. ABVD arm (23 vs. 32).

No new safety signals were identified.