Seattle Genetics Announces Commercial And Regulatory Progress Under ADCETRIS (Brentuximab Vedotin) Collaboration With Takeda

-$20 Million Milestone Payment Triggered by Annual ADCETRIS Net Sales Exceeding $200 Million in Takeda’s Territory During 2015-

-European Commission Recently Approved a Type II Label Variation that Includes Data on the Retreatment of Relapsed or Refractory (R/R) Hodgkin lymphoma or R/R Systemic ALCL-

BOTHELL, Wash.--(BUSINESS WIRE)--Seattle Genetics, Inc., (Nasdaq: SGEN) today announced that it will receive a one-time $20 million milestone payment under its ADCETRIS (brentuximab vedotin) collaboration with Takeda Pharmaceutical Company Limited (Takeda). The milestone was triggered by Takeda surpassing annual ADCETRIS net sales of $200 million in its territory during 2015. The milestone will be recognized as royalty revenue in the first quarter of 2016. In addition, the company announced that the European Commission recently approved a Type II variation that includes data on the retreatment of adult patients with relapsed or refractory (R/R) Hodgkin lymphoma or R/R systemic anaplastic large cell lymphoma (sALCL) who previously responded to ADCETRIS and who later relapse. The label update follows a positive opinion from the Committee for Medicinal Products for Human Use (CHMP) in October 2015.

“This sales milestone and recent label update in Europe to include data on retreatment underscore the strong commercial and regulatory progress that Takeda has made in its territory”

“This sales milestone and recent label update in Europe to include data on retreatment underscore the strong commercial and regulatory progress that Takeda has made in its territory,” said Clay B. Siegall, Ph.D., President and Chief Executive Officer at Seattle Genetics. “We and Takeda are focused on the goal of establishing ADCETRIS as the foundation of care for CD30-expressing lymphomas through global commercialization activities and a broad clinical development program that includes three phase 3 trials.”

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 is entitled to royalties based on a percentage of Takeda’s net sales in its territory at rates that range from the mid-teens to the mid-twenties based on sales volume subject to offsets for royalties paid by Takeda to third parties. In addition, Seattle Genetics is entitled to receive progress- and sales-dependent milestone payments based on net sales of ADCETRIS within Takeda’s licensed territory. 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 ADCETRIS^® (Brentuximab Vedotin)
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. CD30 is a member of the tumor necrosis factor receptor (TNFR) superfamily. In HL, CD30 may be involved in tumor cell proliferation by interacting with immune cells in the tumor microenvironment.

ADCETRIS for intravenous injection has received approval from the FDA for three indications: (1) regular approval for the treatment of patients with classical HL 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 HL 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 HL 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 HL 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. In January 2016, the European Commission approved a Type II variation to include data on the retreatment of adult patients with Hodgkin lymphoma or sALCL who previously responded to ADCETRIS and who later relapse. ADCETRIS has received marketing authorization by regulatory authorities in 60 countries. See important safety information below.

About Seattle Genetics
Seattle Genetics is a biotechnology company focused on the development and commercialization of innovative antibody-based therapies for the treatment of cancer. Seattle Genetics is leading the field in developing antibody-drug conjugates (ADCs), a technology designed to harness the targeting ability of antibodies to deliver cell-killing agents directly to cancer cells. The company’s lead product, ADCETRIS^® (brentuximab vedotin), is a CD30-targeted ADC that, in collaboration with Takeda Pharmaceutical Company Limited, is commercially available in 60 countries, including the U.S., Canada, Japan and members of the European Union. Additionally, ADCETRIS is being evaluated broadly in more than 70 ongoing clinical trials in CD30-expressing malignancies. Seattle Genetics is also advancing vadastuximab talirine (SGN-CD33A; 33A), an ADC that is expected to advance into a phase 3 trial for acute myeloid leukemia in 2016. Beyond ADCETRIS and 33A, the company is developing a robust pipeline of clinical-stage programs, including denintuzumab mafodotin (SGN-CD19A; 19A), SGN-LIV1A, ASG-15ME, ASG-22ME (enfortumab vedotin), SGN-CD70A and SEA-CD40. Seattle Genetics has collaborations for its ADC technology with a number of leading biotechnology and pharmaceutical companies, including AbbVie, Agensys (an affiliate of Astellas), Bayer, Genentech, GlaxoSmithKline and Pfizer. More information can be found at www.seattlegenetics.com.

ADCETRIS (brentuximab vedotin) U.S. Important Safety Information

BOXED WARNING
Progressive multifocal leukoencephalopathy (PML): JC virus infection resulting in PML and death can occur in patients receiving ADCETRIS^® (brentuximab vedotin).

Contraindication
ADCETRIS is contraindicated with concomitant bleomycin due to pulmonary toxicity (e.g., interstitial infiltration and/or inflammation).

Warnings and Precautions

• Peripheral neuropathy: ADCETRIS treatment causes a peripheral neuropathy that is predominantly sensory. Cases of peripheral motor neuropathy have also been reported. ADCETRIS-induced peripheral neuropathy is cumulative. Monitor patients for symptoms of neuropathy, such as hypoesthesia, hyperesthesia, paresthesia, discomfort, a burning sensation, neuropathic pain or weakness and institute dose modifications accordingly.
• Anaphylaxis and infusion reactions: Infusion-related reactions, including anaphylaxis, have occurred with ADCETRIS. Monitor patients during infusion. If an infusion-related reaction occurs, interrupt the infusion and institute appropriate medical management. If anaphylaxis occurs, immediately and permanently discontinue the infusion and administer appropriate medical therapy.
• Hematologic toxicities: Prolonged (=1 week) severe neutropenia and Grade 3 or 4 thrombocytopenia or anemia can occur with ADCETRIS. Febrile neutropenia has been reported with ADCETRIS. Monitor complete blood counts prior to each dose of ADCETRIS and consider more frequent monitoring for patients with Grade 3 or 4 neutropenia. Monitor patients for fever. If Grade 3 or 4 neutropenia develops, consider dose delays, reductions, discontinuation, or G-CSF prophylaxis with subsequent doses.
• Serious infections and opportunistic infections: Infections such as pneumonia, bacteremia, and sepsis or septic shock (including fatal outcomes) have been reported in patients treated with ADCETRIS. Closely monitor patients during treatment for the emergence of possible bacterial, fungal or viral infections.
• Tumor lysis syndrome: Closely monitor patients with rapidly proliferating tumor and high tumor burden.
• Increased toxicity in the presence of severe renal impairment: The frequency of =Grade 3 adverse reactions and deaths was greater in patients with severe renal impairment compared to patients with normal renal function. Avoid the use of ADCETRIS in patients with severe renal impairment.
• Increased toxicity in the presence of moderate or severe hepatic impairment: The frequency of =Grade 3 adverse reactions and deaths was greater in patients with moderate or severe hepatic impairment compared to patients with normal hepatic function. Avoid the use of ADCETRIS in patients with moderate or severe hepatic impairment.
• Hepatotoxicity: Serious cases of hepatotoxicity, including fatal outcomes, have occurred with ADCETRIS. Cases were consistent with hepatocellular injury, including elevations of transaminases and/or bilirubin, and occurred after the first dose of ADCETRIS or rechallenge. Preexisting liver disease, elevated baseline liver enzymes, and concomitant medications may also increase the risk. Monitor liver enzymes and bilirubin. Patients experiencing new, worsening, or recurrent hepatotoxicity may require a delay, change in dose, or discontinuation of ADCETRIS.
• Progressive multifocal leukoencephalopathy (PML): JC virus infection resulting in PML and death has been reported in ADCETRIS-treated patients. First onset of symptoms occurred at various times from initiation of ADCETRIS therapy, with some cases occurring within 3 months of initial exposure. In addition to ADCETRIS therapy, other possible contributory factors include prior therapies and underlying disease that may cause immunosuppression. Consider the diagnosis of PML in any patient presenting with new-onset signs and symptoms of central nervous system abnormalities. Hold ADCETRIS if PML is suspected and discontinue ADCETRIS if PML is confirmed.
• Pulmonary Toxicity: Events of noninfectious pulmonary toxicity including pneumonitis, interstitial lung disease, and acute respiratory distress syndrome, some with fatal outcomes, have been reported. Monitor patients for signs and symptoms of pulmonary toxicity, including cough and dyspnea. In the event of new or worsening pulmonary symptoms, hold ADCETRIS dosing during evaluation and until symptomatic improvement.
• Serious dermatologic reactions: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN), including fatal outcomes, have been reported with ADCETRIS. If SJS or TEN occurs, discontinue ADCETRIS and administer appropriate medical therapy.
• Embryo-fetal toxicity: Fetal harm can occur. Advise pregnant women of the potential hazard to the fetus.

Most Common Adverse Reactions:
ADCETRIS was studied as monotherapy in 160 patients with relapsed classical HL and sALCL in two uncontrolled single-arm trials. Across both trials, the most common adverse reactions (=20%), regardless of causality, were neutropenia, peripheral sensory neuropathy, fatigue, nausea, anemia, upper respiratory tract infection, diarrhea, pyrexia, rash, thrombocytopenia, cough and vomiting.

ADCETRIS was studied in 329 patients with classical HL at high risk of relapse or progression post-auto-HSCT in a placebo-controlled randomized trial. The most common adverse reactions (=20%) in the ADCETRIS-treatment arm (167 patients), regardless of causality, were neutropenia, peripheral sensory neuropathy, thrombocytopenia, anemia, upper respiratory tract infection, fatigue, peripheral motor neuropathy, nausea, cough, and diarrhea.

Drug Interactions:
Concomitant use of strong CYP3A4 inhibitors or inducers, or P-gp inhibitors, has the potential to affect the exposure to monomethyl auristatin E (MMAE).

Use in Specific Populations:
MMAE exposure and adverse reactions are increased in patients with moderate or severe hepatic impairment or severe renal impairment. Avoid use.

For additional Important Safety Information, including Boxed WARNING, please see the full Prescribing Information for ADCETRIS at http://www.seattlegenetics.com/pdf/adcetris_USPI.pdf.

Certain of the statements made in this press release are forward looking, such as those, among others, relating to the potential commercial opportunity for ADCETRIS and the potential for approval of ADCETRIS in other countries and for other disease settings. Actual results or developments may differ materially from those projected or implied in these forward-looking statements. Factors that may cause such a difference include risks that ADCETRIS may not receive the regulatory approvals expected or even if regulatory approvals are obtained, payment and reimbursement for the use of ADCETRIS may be less than projected. More information about the risks and uncertainties faced by Seattle Genetics is contained in the company’s 10-Q for the quarter ended September 30, 2015 filed with the Securities and Exchange Commission. Seattle Genetics disclaims any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.