Expand Clinical Research on Patients with Progressive Disease

SOUTH SAN FRANCISCO, August 13, 2018– Sutro Biopharma, Inc.,and The Leukemia & Lymphoma Society® , or LLS, are partnering to develop STRO-001, Sutro’s CD74-targeting antibody-drug conjugate, to treat relapsed and/or refractory multiple myeloma and non-Hodgkin’s lymphoma.

CD74 is a protein highly expressed in B-cell malignancies such as myeloma and lymphoma.

LLS has agreed to contribute clinical development funding for STRO-001 — Sutro’s first internally-developed product candidate — through its Therapy Acceleration Program, which forges collaborations with biotechnology companies to help bring innovative therapies to patients faster.

Sutro intends to use the funding for a Phase 1 study, initiated in April of this year, to evaluate STRO-001 for treating multiple myeloma, diffuse large B-cell lymphoma, mantle cell lymphoma andindolent lymphomas, such asfollicular lymphoma.

The clinical trial is currently open and enrolling patients at City of Hope Comprehensive Cancer Center, Duarte, CA; Medical College of Wisconsin, Milwaukee; Texas Oncology, Austin; Rocky Mountain Cancer Centers, Aurora, CO; and Virginia Cancer Specialists in Fairfax. Sutro plans to add more sites later this year.

The study’s primary outcome measures are safety and tolerability of STRO-001 in dose escalation, and preliminary anti-tumor activity in dose expansion. This is the first clinical trial on a product candidate created with cell-free protein synthesis.

Sutro is obligated to make payments to The Leukemia & Lymphoma Society based on pre-specified late-stage clinical development, regulatory and commercialization milestones.

Financial terms of the partnership have not been disclosed.

“LLS is committed to advancing therapies to address critical unmet need,” said Lee Greenberger, Ph.D., LLS chief scientific officer. “New options for therapies are vital for patients with non-Hodgkin’s lymphoma and myeloma who do not respond to available treatments.  Sutro’s approach offers a promising option for these patients.”

Sutro CEO Bill Newell said: “Despite treatment advances, many multiple myeloma and non-Hodgkin’s lymphoma patients have treatment-resistant disease or continue to suffer relapses, and their physicians have limited options, underscoring the need fornovel targeted therapies.

“Our collaboration with The Leukemia & Lymphoma Society will facilitate expansion of clinical research on STRO-001 for patients with progressive disease following standard of care therapies.”

Added Dr. Arturo Molina, a medical oncologist and Sutro’s chief medical officer: “It’s difficult to find well-tolerated treatments that effectively target tumors in relapsed and refractory lymphoma and multiple myeloma. This partnership will enable us to examine if STRO-001 can be a potent new option for targeting these tumors.”

Preclinical research findings presented by Sutro at the American Society of Hematology’s 2017 annual meeting and at other scientific meetings last year highlighted the specificity of STRO-001’s anti-CD74 antibody component, the high prevalence of CD74 expression in myeloma and lymphoma tumor samples, STRO-001’s potent in vitrocytotoxicity in multiple B-cell tumor cell lines and its anti-tumor activity in multiple myeloma and lymphoma xenograft models.

Sutro’s Proprietary Cell-Free Platform

STRO-001 was developed with Sutro’s XpressCF⁺™ proprietary cell-free protein synthesis and site-specific conjugation platforms, which enable rapid evaluation of a wide variety of protein structures and design and manufacturing of a highly-optimized single molecular species, rather than the usual mixture of imprecisely conjugated antibodies that comprise an antibody drug conjugate made by conventional cell-based manufacturing.

This cell-free technology should allow Sutro to move optimized proteins seamlessly through every stage of development — from discovery through commercial-stage production, without needing to generate individual cell lines for protein production.

Sutro’s manufacturing center in San Carlos, California, is built to maximize the speed and efficiency of protein production and is the first and only current cGMP-compliant, scalable cell-free manufacturing facility.

Added Dr. Trevor Hallam, Sutro’s chief scientific officer: “With XpressCF⁺™, we incorporate non-natural amino acids into specific positions on the generated antibody for site-specific conjugation of cytotoxins with a linker and warhead to enable consistent, stable, pinpoint placement of STRO-001’s toxic payload. This leads to highly efficient delivery of the cytotoxin to tumor cells. By contrast, earlier generations of ADCs can have unpredictable pharmacologic properties, resulting in the potential for sub-optimal stability, compromised efficacy and poor tolerability for patients.”

About Sutro Biopharma

Sutro Biopharma, located in South San Francisco, is a clinical-stage drug discovery, development and manufacturing company creating a broad variety of next-generation protein therapeutics for oncology based on its proprietary, integrated cell-free protein synthesis and site-specific conjugation platforms, XpressCF⁺™ and XpressCF⁺™.

Sutro is dedicated to transforming the lives of cancer patients by creating medicines with improved therapeutic profiles for areas of unmet need.

To date, Sutro has designed cytokine-based immuno-oncology therapies, antibody-drug conjugates, and bispecific antibodies primarily directed at clinically-validated targets for which the current standard of care is suboptimal.

Sutro’s platform allows it to accelerate discovery and development of first-in-class and best-in-class molecules through rapid and systematic evaluation of protein structure-activity relationships to create optimized homogeneous product candidates.

In addition to developing its own oncology pipeline, Sutro is collaborating with select pharmaceutical and biotech companies to discover and develop novel, next generation therapeutics.  As the pace of clinical development accelerates, Sutro and its partners are demonstrating a more efficient approach to killing tumors without harming healthy cells.

Follow Sutro on Twitter, @Sutrobio, and at www.sutrobio.com to learn more about our passion for changing the future of oncology. 

About The Leukemia & Lymphoma Society

The Leukemia & Lymphoma Society®, or LLS, is the world’s largest voluntary health agency dedicated to fighting blood cancer. The LLS mission: Cure leukemia, lymphoma, Hodgkin’s disease and myeloma, and improve the quality of life of patients and their families. LLS funds lifesaving blood cancer research around the world, provides free information and support services, and is the voice for all blood cancer patients seeking access to quality, affordable, coordinated care.

Founded in 1949 and headquartered in Rye Brook, NY, LLS has chapters throughout the United States and Canada. To learn more, visit www.LLS.org. Patients should contact the Information Resource Center at (800) 955-4572, Monday through Friday, 9 a.m. to 9 p.m. ET.

For additional information visit lls.org/lls-newsnetwork. Follow us on Facebook, Twitter, and Instagram.

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Media Contacts

David Schull
Russo Partners
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Amiad Finkelthal
Russo Partners
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