Seattle Genetics and Unum Therapeutics Enter into Strategic Cancer Immunotherapy Collaboration

-Collaboration Combines Seattle Genetics’ Expertise in Cancer Targets and Antibody-Based Therapies with Unum’s Novel Antibody-Coupled T-cell Receptor (ACTR) Technology-

-Companies to Focus on the Development of Next Generation Cellular Immunotherapy Agents that Combine Unum’s Universal T-cell Approach with Select Seattle Genetics Targets and Antibodies-

BOTHELL, Wash. & CAMBRIDGE, Mass.--(BUSINESS WIRE)--Jun. 8, 2015-- Seattle Genetics, Inc. (Nasdaq: SGEN) and Unum Therapeutics announced today that the two companies have entered into a strategic collaboration and license agreement to develop and commercialize novel antibody-coupled T-cell receptor (ACTR) therapies for cancer.

Unum’s proprietary ACTR technology enables programming of a patient’s T-cells to attack tumor cells when co-administered with tumor-specific therapeutic antibodies. Seattle Genetics, through its extensive work in the field of antibody-drug conjugates (ADCs), has a substantial portfolio of cancer targets and tumor-specific monoclonal antibodies from which programs will be selected for the collaboration.

“This collaboration is an exciting extension of our work over more than 17 years, empowering antibodies in order to provide new therapeutic options for cancer patients,” said Clay B. Siegall, Ph.D., President and Chief Executive Officer of Seattle Genetics. “Unum’s innovative technology for a universal, antibody-directed cellular immunotherapy is differentiated from other engineered T-cell approaches, and may have broad applicability across a range of cancer targets. We are pleased to be collaborating with one of the most promising companies in the emerging field of cellular immunotherapy to develop new treatment options for cancer patients with unmet medical needs.”

“Unum’s strategy is to develop and commercialize a universal cellular immunotherapy that can be used in combination with a variety of antibodies to attack a wide range of hematological and solid tumors,” said Charles Wilson, Ph.D., President and Chief Executive Officer of Unum Therapeutics. “We believe that our unique approach has the potential to advance beyond the safety and efficacy limitations of current generation T-cell approaches. We are delighted to collaborate with Seattle Genetics in the development of ACTR therapies. Their leadership in antibody-based therapies and expertise in the development of cancer treatments will be invaluable as we work together to bring potentially breakthrough therapies to patients.”

Under the terms of the agreement, Seattle Genetics will make an upfront payment of $25 million and an equity investment of $5 million in Unum’s next round of private financing. The companies will initially develop two ACTR products incorporating Seattle Genetics’ antibodies, and Seattle Genetics has an option to expand the collaboration to include a third ACTR product. Unum will conduct preclinical research and clinical development activities through phase 1 with funding from Seattle Genetics. The companies will work together to co-develop and jointly fund programs after phase 1 unless either company opts out. Seattle Genetics and Unum will co-commercialize and share profits 50/50 on any co-developed programs in the United States. Seattle Genetics will retain exclusive commercial rights outside of the United States, paying Unum high single to mid-double digit royalties on ex-U.S. sales. Potential option fee and progress-dependent milestone payments to Unum under the collaboration may total up to $615 million across all three ACTR programs.

As a result of the amounts paid up front and the additional development activities expected under this deal, Seattle Genetics will provide revised 2015 financial guidance in connection with announcing its second quarter financial results currently planned for July 30, 2015.

About ACTR Technology

ACTR is a chimeric protein that combines components from receptors normally found on two different human immune cell types – natural killer (NK) cells and T-cells – to create a novel cancer cell killing activity. T-cells bearing the ACTR receptor can be directed to attack tumor cells by providing a monoclonal antibody that binds to antigens on the cancer cell surface and then acts as a bridge to the ACTR T-cell, enabling tumor cell killing. Unum has built a platform for cancer treatment based upon ACTR. In contrast to other approaches that are limited to a single target and treat a narrow set of tumors, Unum’s approach is not restricted by antigen and may have applications for treating many types of cancers.

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 for two indications in more than 55 countries, including the U.S., Canada, Japan and members of the European Union. Additionally, ADCETRIS is being evaluated broadly in more than 30 ongoing clinical trials in CD30-expressing malignancies. Seattle Genetics is also advancing a robust pipeline of clinical-stage programs, including SGN-CD19A, SGN-CD33A, SGN-LIV1A, SGN-CD70A, ASG-22ME, ASG-15ME 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.

About Unum Therapeutics

Unum Therapeutics uses proprietary T-cell engineering technology in combination with tumor-targeting antibodies to activate the body’s own immune system to fight cancer. Unum’s lead program, based on its Antibody-Coupled T-cell Receptor (ACTR) technology, recently entered Phase 1 clinical testing to assess safety and efficacy. Unum is seeking partners interested in using the ACTR technology to arm proprietary tumor-specific antibodies with a T-cell to improve their therapeutic potential. The company is headquartered in Cambridge, MA. For more information, visit www.unumrx.com.

For Seattle Genetics:

Certain of the statements made in this press release are forward looking, such as those, among others, relating to the therapeutic potential of ACTR-based products. 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 the inability to show sufficient activity in clinical trials and the risk of adverse events as these programs advance in clinical trials. More information about the risks and uncertainties faced by Seattle Genetics is contained in the company’s 10-Q for the quarter ended March 31, 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.

Source: Seattle Genetics, Inc.

Seattle Genetics:
Investors:
Peggy Pinkston
425-527-4160
ppinkston@seagen.com
or
Media:
Tricia Larson
425-527-4180
tlarson@seagen.com
or
Unum Therapeutics:
Mariesa Kemble
Sam Brown Inc.
608-850-4745
mariesakemble@sambrown.com