-Randomized Phase 3 Clinical Trial with ADCETRIS Met Primary Endpoint, Demonstrating Highly Statistically Significant Improvement in Rate of Objective Response Lasting at Least Four Months-
-Abstract to be Submitted to ASH for Presentation at the 2016 Annual Meeting-

BOTHELL, WA & CAMBRIDGE, MA, USA & OSAKA, Japan I August 1 2016 I Takeda Pharmaceutical Company Limited (TSE:4502) and Seattle Genetics, Inc. (NASDAQ:SGEN) today announced that the Phase 3 ALCANZA clinical trial evaluating ADCETRIS (brentuximab vedotin) in patients with cutaneous T-cell lymphoma (CTCL) met its primary endpoint, demonstrating a highly statistically significant improvement in the rate of objective response lasting at least four months (ORR4). This randomized trial, which received a Special Protocol Assessment (SPA) from the U.S. Food and Drug Administration (FDA) and scientific advice from the European Medicines Agency (EMA), compared the use of single-agent ADCETRIS to a control arm of investigator’s choice of standard therapies, methotrexate or bexarotene, in 131 patients with CD30-expressing CTCL who received prior systemic or radiation therapy. ADCETRIS is an antibody-drug conjugate (ADC) directed to CD30 which is expressed on skin lesions in approximately 50 percent of patients with CTCL. ADCETRIS is currently not approved for the treatment of CTCL.

The results of the ALCANZA trial demonstrated that treatment with ADCETRIS resulted in a highly statistically significant improvement in the ORR4 versus the control arm as assessed by an independent review committee (p-value <0.0001). The ORR4 was 56.3 percent in the ADCETRIS arm compared to 12.5 percent in the control arm. The key secondary endpoints specified in the protocol, including complete response rate, progression-free survival and reduction in the burden of symptoms during treatment, were all highly statistically significant in favor of the ADCETRIS arm. The safety profile associated with ADCETRIS from the ALCANZA trial was generally consistent with the existing prescribing information.

An abstract will be submitted for data presentation at the American Society of Hematology (ASH) annual meeting, December 3-6, 2016, in San Diego, California.

“These remarkable, clinically meaningful results from the completed ALCANZA trial represent an important milestone for the ADCETRIS program. If this new indication is approved by regulatory authorities, ADCETRIS may offer a novel treatment option for CTCL patients,” said Dirk Huebner, M.D., Executive Medical Director, Oncology Therapeutic Area Unit, Takeda Pharmaceutical Company. “We are excited by the data, which showed a significant improvement in the primary endpoint of ORR4 and all key secondary endpoints, along with a manageable safety profile. This outcome further establishes our commitment to patients living with CD30-expressing disease, and we look forward to sharing these data with regulatory authorities globally.”

“Cutaneous T-cell lymphoma is a debilitating, disfiguring and painful disease, and there is a significant need for additional effective treatment options with meaningful durable responses. This is the first Phase 3 randomized trial in CTCL versus an active control to read out, and we are thrilled to have successfully demonstrated the positive impact of using ADCETRIS for patients enrolled in this study,” said Clay Siegall, Ph.D., President and Chief Executive Officer of Seattle Genetics. “We anticipate reporting more complete ALCANZA data at the ASH annual meeting in December and intend to submit a supplemental Biologics License Application to the FDA in the first half of 2017 for approval in this setting.”

Phase 3 ALCANZA Clinical Trial Design

The ALCANZA trial is a randomized, open-label Phase 3 study designed to evaluate single-agent ADCETRIS versus a control arm of investigator’s choice of standard therapies, methotrexate or bexarotene, in patients with CD30-expressing CTCL, including those with primary cutaneous anaplastic large cell lymphoma (pcALCL) or mycosis fungoides (MF). The primary endpoint is ORR4 as assessed by Global Response Score in the ADCETRIS arm compared to the control arm. Key secondary endpoints are complete response rate, progression-free survival and reduction in the burden of symptoms during treatment. The clinical trial enrolled 131 patients at 50 sites globally. Patients with pcALCL must have received at least one prior systemic or radiation therapy and patients with MF must have received at least one prior systemic therapy. Patients received ADCETRIS every three weeks versus investigator’s choice for up to approximately one year. This international multi-center trial has been conducted in North and South America, Europe and Australia under operational responsibility of Takeda Pharmaceuticals.

ADCETRIS received orphan drug designation from the FDA for the treatment of MF, which is the most common type of CTCL. ADCETRIS also received orphan drug designation from the European Commission for CTCL, including subtypes pcALCL and MF.

Please see Important Safety Information at the end of this press release.

About CTCL

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. Cutaneous lymphomas are a category of non-Hodgkin lymphoma that primarily involve the skin. According to the Cutaneous Lymphoma Foundation, CTCL is the most common type of cutaneous lymphoma and typically presents with red, scaly patches or thickened plaques of skin that often mimic eczema or chronic dermatitis. Progression from limited skin involvement may be accompanied by tumor formation, ulceration and exfoliation, complicated by itching and infections. Advanced stages are defined by involvement of lymph nodes, peripheral blood and internal organs. According to published literature, CD30 is expressed on skin lesions in approximately 50 percent of CTCL patients.

The standard treatment for systemically pretreated CTCL includes skin-directed therapies, radiation and systemic therapies. The systemic therapies currently approved for treatment have demonstrated 30 to 45 percent objective response rates, with low complete response rates.

About ADCETRIS

ADCETRIS is being evaluated broadly in more than 70 ongoing clinical trials, including two Phase 3 studies, ECHELON-1 in frontline classical Hodgkin lymphoma and ECHELON-2 in frontline mature T-cell lymphomas, as well as trials in many additional types of CD30-expressing malignancies, including B-cell lymphomas.

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 for intravenous injection has received approval from the FDA for three indications: (1) regular approval for the treatment of patients with classical Hodgkin lymphoma after failure of autologous hematopoietic stem cell transplantation (auto-HSCT) or after failure of at least two prior multi-agent chemotherapy regimens in patients who are not auto-HSCT candidates, (2) regular approval for the treatment of classical Hodgkin lymphoma patients at high risk of relapse or progression as post-auto-HSCT consolidation, and (3) accelerated approval for the treatment of patients with systemic anaplastic large cell lymphoma (sALCL) after failure of at least one prior multi-agent chemotherapy regimen. The sALCL indication is approved under accelerated approval based on overall response rate. Continued approval for the sALCL indication may be contingent upon verification and description of clinical benefit in confirmatory trials. Health Canada granted ADCETRIS approval with conditions for relapsed or refractory Hodgkin lymphoma and sALCL.

ADCETRIS was granted conditional marketing authorization by the European Commission in October 2012 for two indications: (1) for the treatment of adult patients with relapsed or refractory CD30-positive Hodgkin lymphoma following autologous stem cell transplant (ASCT), or following at least two prior therapies when ASCT or multi-agent chemotherapy is not a treatment option, and (2) the treatment of adult patients with relapsed or refractory sALCL. ADCETRIS has received marketing authorization by regulatory authorities in more than 60 countries for relapsed or refractory Hodgkin lymphoma and sALCL. In June 2016, the European Commission extended the current conditional marketing authorization of ADCETRIS and approved ADCETRIS for the treatment of adult patients with CD30+ Hodgkin lymphoma at increased risk of relapse or progression following ASCT. See important safety information 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 Takeda

Takeda Pharmaceutical Company Limited is a global, R&D-driven pharmaceutical company committed to bringing better health and a brighter future to patients by translating science into life-changing medicines. Takeda focuses its research efforts on oncology, gastroenterology and central nervous system therapeutic areas. It also has specific development programs in specialty cardiovascular diseases as well as late-stage candidates for vaccines. Takeda conducts R&D both internally and with partners to stay at the leading edge of innovation. New innovative products, especially in oncology and gastroenterology, as well as its presence in emerging markets, fuel the growth of Takeda. More than 30,000 Takeda employees are committed to improving quality of life for patients, working with our partners in health care in more than 70 countries. For more information, visit http://www.takeda.com/news.

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.

About Seattle Genetics

Seattle Genetics is an innovative biotechnology company that develops and commercializes novel antibody-based therapies for the treatment of cancer. The company’s industry-leading antibody-drug conjugate (ADC) technology harnesses the targeting ability of antibodies to deliver cell-killing agents directly to cancer cells. ADCETRIS® (brentuximab vedotin), the company’s lead product, in collaboration with Takeda Pharmaceutical Company Limited, is the first in a new class of ADCs commercially available globally in 65 countries for relapsed classical Hodgkin lymphoma and relapsed systemic anaplastic large cell lymphoma (sALCL). Seattle Genetics is also advancing vadastuximab talirine (SGN-CD33A; 33A), an ADC in a Phase 3 trial for acute myeloid leukemia. Headquartered in Bothell, Washington, Seattle Genetics is developing a robust pipeline of innovative therapies for blood-related cancers and solid tumors designed to address significant unmet medical needs and improve treatment outcomes for patients. The company has collaborations for its proprietary ADC technology with a number of companies including AbbVie, Astellas, Bayer, Genentech, GlaxoSmithKline and Pfizer. More information can be found at www.seattlegenetics.com

SOURCE: Seattle Genetics