Silverback Therapeutics™ ("Silverback") ("the Company"), a private biopharmaceutical company pioneering a new class of immune-modulating ImmunoTAC™ drug conjugates targeting previously inaccessible disease pathways, today announced the close of an oversubscribed $78.5 million Series B financing round. U.S. Venture Partners ("USVP") led the round, with participation from new investors including Nextech Invest Ltd., Hunt Investment Group, Pontifax Venture Capital, Colt Ventures LP and NS Investment. Existing investors participating in the financing include OrbiMed Advisors LLC, Bristol-Meyers Squibb and Alexandria Venture Investments, LLC. Silverback will use the proceeds to support ongoing development of SBT6050, an anti-HER2 antibody conjugated to a potent TLR8 agonist for the treatment of HER2-expressing solid tumors, and to advance its pipeline of ImmunoTAC™ programs. The Company expects to file an Investigational New Drug Application ("IND") and initiate clinical investigation for SBT6050 this year.

"Our preclinical studies demonstrate that systemic delivery of our TLR8 agonist targeted to HER2-expressing tumors potently activates myeloid cells to kill cancer and reprograms the tumor microenvironment, resulting in durable, curative single-agent activity," said Peter Thompson, M.D., co-founder, Chairman, & CEO, Silverback Therapeutics. "We are pleased to attract a group of world-class investors who believe in our bold vision to develop potent immune-modulating agents that can be delivered systemically, but act locally at the site of disease. With these additional resources, we're focused on advancing our lead program into the clinic this year and progressing our preclinical pipeline assets towards the clinic."

Along with the financing, Jonathan Root, M.D., general partner at USVP, and Thilo Schroeder, Ph.D., partner at Nextech Invest Ltd., have joined Silverback's board of directors.

Dr. Root spent nine years in clinical practice before joining USVP in 1995 and becoming a general partner in 1997. Before USVP, he was on the faculty and clinical staff at The New York Hospital-Cornell Medical Center in New York City. Dr. Root is currently on the boards of several USVP portfolio companies and is also a former board member for the National Venture Capital Association. Dr. Root holds an A.B. in Economics from Dartmouth College, an M.D. from the University of Florida College of Medicine, and an M.B.A. from Columbia University.

Dr. Schroeder joined Nextech as a partner in 2012, helping grow and shape the organization as a leading oncology-focused venture firm. He began his biotech career at the pioneering cancer immunology company Micromet (acquired by Amgen) while studying at Ecole Supérieure de Biotechnologie de Strasbourg. Dr. Schroeder is currently on the boards of several private biotechnology companies. He obtained his Ph.D., focused on protein engineering in the development of Designed Ankyrin Repeat Proteins (DARPins), from the University of Zurich.

"The Silverback team is building a platform technology capable of unlocking potent immuno-modulatory pathways using an established antibody-guided approach for targeting disease sites," said Jonathan Root, M.D., general partner, USVP. "I look forward to supporting the company's evolution as it moves these compelling therapies into the clinic, starting with SBT6050."

About Silverback Therapeutics

Silverback Therapeutics is a privately held biopharmaceutical company advancing a pipeline of therapies that are systemically delivered, but locally active and target fundamental disease pathways. Silverback's ImmunoTAC™ platform enables local modulation of powerful biologic pathways enabling innovative therapeutic approaches to oncology, virology and fibrotic diseases. Silverback's lead candidate, SBT6050, directly and potently activates myeloid cells in HER2-containing tumors leading to eradication of the cancer cells and reprogramming of the tumor microenvironment in preclinical models. Clinical investigation of SBT6050 is expected to begin in 2020. Since its inception in 2016, Silverback has raised over $125 million in venture capital. The Company is headquartered in Seattle, Washington. To learn more, visit www.silverbacktx.com.

About U.S. Venture Partners

U.S. Venture Partners (USVP) is a leading Silicon Valley venture capital firm, partnering with entrepreneurs to transform their ideas into world-changing companies. USVP focuses on early-stage start-ups that transform cybersecurity, enterprise software, consumer and healthcare. USVP has invested in over 400 companies spanning four decades, including Box, Check Point Software, Guidewire, HeartFlow, HotelTonight, Imperva, Inari Medical, Inspire Medical Systems, Intersect ENT, Luminate, Omada Health, Pluto TV, Prevoty, Sequent, ThreatMetrix, Trunk Club, Trusteer, Vontu, Yammer and Zerto. The USVP team consists of former entrepreneurs, technologists, corporate executives, and financial professionals who assist with strategy, scaling, team building, product development, and business development. USVP is based in Menlo Park, California. More information can be found at www.usvp.com.