Seattle Genetics, Inc. (Nasdaq: SGEN) today announced initiation of a phase 1 clinical trial of SEA-CD40 for multiple types of advanced solid tumors. SEA-CD40 is a novel investigational immuno-oncology agent targeted to CD40, a widely expressed stimulatory receptor found on antigen-presenting cells (APCs) which play a role in immune cell activation. SEA-CD40 utilizes Seattle Genetics’ proprietary sugar-engineered antibody (SEA) technology to produce a non-fucosylated antibody targeting CD40. Preclinical data show that SEA-CD40 stimulates the immune system to fight cancer.

“We are pleased to advance our SEA-CD40 immuno-oncology program into the clinic to evaluate it broadly in multiple types of solid tumors,” said Clay B. Siegall, Ph.D., President and Chief Executive Officer of Seattle Genetics. “Our proprietary SEA technology builds on our expertise in empowered, targeted approaches for the treatment of cancer and represents a novel technology designed to increase the potency of monoclonal antibodies through glycoengineering which may lead to an improved antitumor immune response. We look forward to data from the phase 1 trial.”

The study is a phase 1, open-label, multi-center, dose-escalation clinical trial of SEA-CD40 in patients with advanced solid tumors who have failed current standard of care treatments. Expansion cohorts are planned to evaluate SEA-CD40 across up to three cancer indications that will be determined based on data from the dose escalation portion of the study. The primary endpoints are determination of the maximum tolerated dose (MTD) and safety profile of SEA-CD40. In addition, the trial will evaluate antitumor activity, pharmacokinetics and immunological pharmacodynamic effects. The phase 1 trial will enroll approximately 50 patients during dose escalation and up to 90 patients in the expansion cohorts at multiple centers in the United States.

For more information about the trial, including enrolling centers, please visit www.clinicaltrials.gov.

About SEA Technology

Seattle Genetics' proprietary SEA technology is a novel approach to increase the potency of monoclonal antibodies. SEA technology produces a non-fucosylated monoclonal antibody, resulting in an enhanced innate immune response. SEA-CD40 represents the first clinical antibody employing the SEA technology. Enhanced binding to effector cells results in better crosslinking and activation of CD40 signaling in immune cells. This stimulation of the patient’s own immune cells has the potential to result in antitumor activity. Preclinical studies show that the non-fucosylated antibody is a potent stimulator of immune cells that may be able to harness the power of a patients’ immune system to fight cancer.

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 an ADC that, in collaboration with Takeda Pharmaceutical Company Limited, is commercially available for two indications in 50 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. 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.

Certain of the statements made in this press release are forward looking, such as those, among others, relating to the therapeutic potential of SEA-CD40 and expected data from the referenced phase 1 trial. 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 this recently initiated clinical trial and the risk of adverse events as SEA-CD40 advances 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 September 30, 2014 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.