-Data Presented in Oral Session with Simultaneous Publication in The Lancet-

-Randomized Phase 3 Clinical Trial Demonstrated ADCETRIS plus Chemotherapy Resulted in Superior Progression-Free Survival and Overall Survival Compared to a Standard of Care, CHOP-

BOTHELL, WA & CAMBRIDGE, MA, USA & OSAKA, Japan I December 03, 2018 I Seattle Genetics, Inc. (Nasdaq:SGEN) and Takeda Pharmaceutical Company Limited (TSE:4502) announced that data from the ECHELON-2 phase 3 clinical trial will be presented today in an oral session at the 60th American Society of Hematology (ASH) Annual Meeting. The data demonstrated that frontline treatment with ADCETRIS (brentuximab vedotin) in combination with CHP (cyclophosphamide, doxorubicin, prednisone) is effective in extending progression-free survival (PFS) and overall survival (OS) with a safety profile comparable to CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone), a current standard of care in patients with CD30-expressing peripheral T-cell lymphomas (PTCL). These data were also simultaneously published online in The Lancet. ADCETRIS is an antibody-drug conjugate (ADC) directed to CD30, which is expressed on the surface of several types of PTCL.

The positive topline results of the ECHELON-2 phase 3 clinical trial were previously reported in October 2018. In November 2018, ADCETRIS was approved by the U.S. Food and Drug Administration (FDA) for adults with previously untreated systemic anaplastic large cell lymphoma (sALCL) or other CD30-expressing PTCL, including angioimmunoblastic T-cell lymphoma and PTCL not otherwise specified, in combination with CHP. The ECHELON-2 data were the basis of a supplemental Biologics License Application (BLA), which was reviewed by the FDA under its Real-Time Oncology Review Pilot Program and approved less than two weeks after complete submission of the supplemental BLA.

“As clinicians, we are always searching for new strategies to address unmet needs in aggressive blood cancers, and ADCETRIS has proven to be one of those agents that has shown benefit for patients in multiple types of lymphoma and now in frontline PTCL,” said Steven Horwitz, M.D., Department of Medicine, Lymphoma Service, Memorial Sloan Kettering Cancer Center, New York. “This research is important for patients because clinicians now have a novel approach for treating newly diagnosed patients with CD30-expressing PTCL, a group of aggressive cancers. The ECHELON-2 data demonstrates that ADCETRIS plus CHP is superior in extending both progression-free survival and overall survival compared to a current standard of care, CHOP, a multi-agent chemotherapy regimen we have been using in practice for several decades.”

“This is the sixth FDA-approved indication for ADCETRIS in lymphoid malignancies and the second as a frontline treatment in combination with chemotherapy,” said Roger Dansey, M.D., Chief Medical Officer at Seattle Genetics. “The data presented today at ASH underscores that the ADCETRIS combination provides clinically meaningful benefit to patients with previously untreated PTCL and has the potential to be practice changing for these patients.”

“We are pleased to share these impressive results from the ECHELON-2 trial, which build on the efficacy and safety observed with ADCETRIS in a variety of CD30-positive lymphomas,” said Jesús Gómez-Navarro, M.D., Vice President and Head, Oncology Clinical Research and Development, Takeda. “The study demonstrated clinically meaningful outcomes and was the first randomized phase 3 trial in frontline PTCL to show improvement in overall survival. Establishing an optimal therapy for PTCL has been a challenge for physicians, and these findings represent the progress in addressing the unmet needs of people living with this serious disease. We look forward to working with regulatory authorities in our territory to bring a potential new treatment option to patients with PTCL.”

The ECHELON-2 Trial: Results of a Randomized, Double-Blind, Active-Controlled Phase 3 Study of Brentuximab Vedotin and CHP (A+CHP) Versus CHOP in the Frontline Treatment of Patients with CD30+ Peripheral T-Cell Lymphomas (Abstract #997, oral presentation on Monday, December 3, 2018 at 6:15 p.m. PT at the San Diego Convention Center, Room 6F)

ECHELON-2 is a global, randomized, double-blind, multi-center trial evaluating ADCETRIS as part of a frontline combination chemotherapy regimen in patients with previously untreated CD30-expressing PTCL. The primary endpoint is PFS per Blinded Independent Central Review (BICR), with events defined as progression, death, or receipt of chemotherapy for residual or progressive disease. Key secondary endpoints include PFS in patients with sALCL, complete remission (CR) rate, OS and objective response rate (ORR). ECHELON-2 enrolled 452 patients (226 in each arm) at 132 sites in 17 countries across North America, Europe, Asia Pacific and the Middle East. The median age of patients was 58 years. The study enrolled patients with advanced disease (80 percent) and most patients had sALCL (48 percent ALK-negative and 22 percent ALK-positive).

Key findings, which will be presented by Dr. Steven Horwitz and published in The Lancet, include:

  • The ECHELON-2 study met its primary endpoint with ADCETRIS plus CHP demonstrating a statistically significant improvement in PFS as assessed by a BICR (hazard ratio [HR]=0.71; p-value=0.0110). This corresponds to a 29 percent reduction in the risk of progression, death or need for additional anticancer therapy for residual or progressive disease.
  • After a median follow-up time of 36.2 months, the median PFS in the ADCETRIS plus CHP arm was 48.2 months (95% CI, 35.2-not evaluable) compared to 20.8 months (95% CI, 12.7-47.6) in the control arm per BICR assessment. The three-year PFS was 57.1 percent for ADCETRIS plus CHP compared to 44.4 percent in the control arm.
  • Per investigator assessment, ADCETRIS plus CHP demonstrated a statistically significant improvement in PFS (HR=0.70; p-value=0.0096).
  • OS in the ADCETRIS plus CHP arm was statistically significant compared to CHOP (HR=0.66; p-value=0.0244). This corresponds to a 34 percent reduction in the risk of death.
  • After a median follow-up of 42.1 months, the median OS was not reached for either arm of the study. The estimated three-year OS was 76.8 percent for ADCETRIS plus CHP compared to 69.1 percent for CHOP.
  • All other key secondary endpoints, including CR rate and ORR, in addition to PFS in patients with sALCL, were statistically significant in favor of the ADCETRIS plus CHP arm. Per BICR assessment, the CR rate (68 percent versus 56 percent, respectively) and ORR (83 percent versus 72 percent, respectively) for the ADCETRIS plus CHP arm were significantly higher than those treated with CHOP (p-value=0.0066 and p-value=0.0032, respectively). Per investigator assessment, the CR rate and ORR showed a similar benefit for the ADCETRIS plus CHP arm versus CHOP (p-value=0.0043 and p-value=0.0018, respectively).
  • Excluding consolidative stem cell transplant or radiotherapy for consolidation of response to initial therapy, 74 percent of patients in the ADCETRIS plus CHP arm versus 58 percent of patients in the CHOP arm did not require subsequent anticancer therapies for residual or progressive disease. Of the 226 patients who received CHOP, 49 patients (22 percent) received subsequent treatment with an ADCETRIS-containing therapy.
  • The safety profile of ADCETRIS plus CHP in the ECHELON-2 trial was comparable to CHOP and consistent with the established safety profile of ADCETRIS in combination with chemotherapy.
    • The most common treatment-related adverse events of any grade occurring in 20 percent or more of patients in the ADCETRIS plus CHP and CHOP arm were: nausea (46 and 38 percent, respectively), peripheral sensory neuropathy (45 and 41 percent, respectively), neutropenia (38 percent each), diarrhea (38 and 20 percent, respectively), constipation (29 and 30 percent, respectively), alopecia (26 and 25 percent, respectively), pyrexia (26 and 19 percent, respectively), vomiting (26 and 17 percent, respectively), fatigue (24 and 20 percent, respectively) and anaemia (21 and 16 percent, respectively).
    • The most common Grade 3 or higher adverse events occurring in the ADCETRIS plus CHP and CHOP arms were neutropenia (35 and 34 percent, respectively) and anaemia (13 and 10 percent, respectively).
    • The incidence and severity of neutropenia was similar between study arms, and lower in the subset of patients who received primary prophylaxis with granulocyte-colony stimulating factor. Febrile neutropenia was reported in 41 patients (18 percent) in the ADCETRIS plus CHP arm and 33 patients (15 percent) in the CHOP arm.
    • New or worsening treatment-emergent peripheral neuropathy events occurred in 117 patients (52 percent) in the ADCETRIS plus CHP arm and 124 patients (55 percent) in the CHOP arm, with a majority at a maximum severity of Grade 1 (64 and 71 percent, respectively). At last follow-up, peripheral neuropathy returned to baseline or lower in 50 percent of the patients in the ADCETRIS plus CHP arm versus 64 percent in the CHOP arm, and the median time to resolution was 17 weeks and 11.4 weeks, respectively.
    • Adverse events leading to death occurred in seven patients (three percent) in the ADCETRIS plus CHP arm and nine patients (four percent) in the CHOP arm.

Please see Important Safety Information, including Boxed Warning, at the end of this press release.

About T-Cell Lymphomas

Lymphoma is a general term for a group of cancers that originate in the lymphatic system. There are two major categories of lymphoma: Hodgkin lymphoma and non-Hodgkin lymphoma. There are more than 60 subtypes of non-Hodgkin lymphomas which are broadly divided into two major groups: B-cell lymphomas, which develop from abnormal B-lymphocytes, and T-cell lymphomas, which develop from abnormal T-lymphocytes. There are many different forms of T-cell lymphomas, some of which are extremely rare. T-cell lymphomas can be aggressive (fast-growing) or indolent (slow-growing). PTCL accounts for approximately 10 percent of non-Hodgkin lymphoma cases in the U.S. and Europe and may be as high as 24 percent in parts of Asia.

About ADCETRIS (brentuximab vedotin)

ADCETRIS is being evaluated broadly in more than 70 clinical trials in CD30-expressing lymphomas. These include the completed phase 3 ECHELON-2 trial in frontline peripheral T-cell lymphomas (also known as mature T-cell lymphoma), the completed phase 3 ECHELON-1 trial in previously untreated Hodgkin lymphoma, the completed phase 3 ALCANZA trial in cutaneous T-cell lymphoma.

ADCETRIS is an ADC comprising an anti-CD30 monoclonal antibody attached by a protease-cleavable linker to a microtubule disrupting agent, monomethyl auristatin E (MMAE), utilizing Seattle Genetics’ proprietary technology. The ADC employs a linker system that is designed to be stable in the bloodstream but to release MMAE upon internalization into CD30-expressing tumor cells.

ADCETRIS injection for intravenous infusion has received FDA approval for six indications in adult patients with: (1) previously untreated systemic anaplastic large cell lymphoma (sALCL) or other CD30-expressing peripheral T-cell lymphomas (PTCL), including angioimmunoblastic T-cell lymphoma and PTCL not otherwise specified, in combination with cyclophosphamide, doxorubicin, and prednisone, (2) previously untreated Stage III or IV classical Hodgkin lymphoma (cHL), in combination with doxorubicin, vinblastine, and dacarbazine, (3) cHL at high risk of relapse or progression as post-autologous hematopoietic stem cell transplantation (auto-HSCT) consolidation, (4) cHL after failure of auto-HSCT or failure of at least two prior multi-agent chemotherapy regimens in patients who are not auto-HSCT candidates, (5) sALCL after failure of at least one prior multi-agent chemotherapy regimen, and (6) primary cutaneous anaplastic large cell lymphoma (pcALCL) or CD30-expressing mycosis fungoides (MF) who have received prior systemic therapy.

Health Canada granted ADCETRIS approval with conditions for relapsed or refractory Hodgkin lymphoma and sALCL in 2013, and non-conditional approval for post-autologous stem cell transplantation (ASCT) consolidation treatment of Hodgkin lymphoma patients at increased risk of relapse or progression.

ADCETRIS received conditional marketing authorization from the European Commission in October 2012. The approved indications in Europe are: (1) for the treatment of adult patients with relapsed or refractory CD30-positive Hodgkin lymphoma following ASCT, or following at least two prior therapies when ASCT or multi-agent chemotherapy is not a treatment option, (2) the treatment of adult patients with relapsed or refractory sALCL, (3) for the treatment of adult patients with CD30-positive Hodgkin lymphoma at increased risk of relapse or progression following ASCT, and (4) for the treatment of adult patients with CD30-positive cutaneous T-cell lymphoma (CTCL) after at least one prior systemic therapy.

ADCETRIS has received marketing authorization by regulatory authorities in 72 countries for relapsed or refractory Hodgkin lymphoma and sALCL. See select important safety information, including Boxed Warning, below.

Seattle Genetics and Takeda are jointly developing ADCETRIS. Under the terms of the collaboration agreement, Seattle Genetics has U.S. and Canadian commercialization rights and Takeda has rights to commercialize ADCETRIS in the rest of the world. Seattle Genetics and Takeda are funding joint development costs for ADCETRIS on a 50:50 basis, except in Japan where Takeda is solely responsible for development costs.

About Seattle Genetics

Seattle Genetics, Inc. is an emerging multi-product, global biotechnology company that develops and commercializes transformative therapies targeting cancer to make a meaningful difference in people’s lives. ADCETRIS® (brentuximab vedotin) utilizes the company’s industry-leading antibody-drug conjugate (ADC) technology and is currently approved for the treatment of multiple CD30-expressing lymphomas. Beyond ADCETRIS, the company has established a pipeline of novel targeted therapies at various stages of clinical testing, including three in ongoing pivotal trials for solid tumors. Enfortumab vedotin for metastatic urothelial cancer and tisotumab vedotin for metastatic cervical cancer utilize our proprietary ADC technology. Tucatinib, a small molecule tyrosine kinase inhibitor, is in a pivotal trial for HER2-positive metastatic breast cancer. In addition, we are leveraging our expertise in empowered antibodies to build a portfolio of proprietary immuno-oncology agents in clinical trials targeting hematologic malignancies and solid tumors. The company is headquartered in Bothell, Washington, and has a European office in Switzerland. For more information on our robust pipeline, visit www.seattlegenetics.com and follow @SeattleGenetics on Twitter.

About Takeda Pharmaceutical Company

Takeda Pharmaceutical Company Limited (TSE: 4502) is a global, research and development-driven pharmaceutical company committed to bringing better health and a brighter future to patients by translating science into life-changing medicines. Takeda focuses its R&D efforts on oncology, gastroenterology and neuroscience therapeutic areas plus vaccines. Takeda conducts R&D both internally and with partners to stay at the leading edge of innovation. Innovative products, especially in oncology and gastroenterology, as well as Takeda’s presence in emerging markets, are currently fueling the growth of Takeda. Approximately 30,000 Takeda employees are committed to improving quality of life for patients, working with Takeda’s partners in health care in more than 70 countries.

For more information, visit https://www.takeda.com/newsroom/.

Additional information about Takeda is available through its corporate website, www.takeda.com, and additional information about Takeda Oncology, the brand for the global oncology business unit of Takeda Pharmaceutical Company Limited, is available through its website, www.takedaoncology.com.

SOURCE: Seattle Genetics