
Earlier today Sutro Biopharma, a clinical-stage drug discovery, development and manufacturing company, and The Leukemia & Lymphoma Society®, the world’s largest voluntary health agency dedicated to fighting blood cancer, confirmed that they are partnering to develop Sutro’s CD74-targeting antibody-drug conjugate STRO-001. The investigational drug is being developed for the treatment of patients with 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.
Clinical trials
The Leukemia & Lymphoma Society has agreed to contribute clinical development funding for STRO-001, Sutro’s first internally-developed product candidate, through its Therapy Acceleration Program. This program which forges collaborations with biotechnology companies to help bring innovative therapies to patients faster.
As part of the agreement, Sutro intends to use the funding for a Phase I study, initiated in April of this year, to evaluate STRO-001 for treating multiple myeloma, diffuse large B-cell lymphoma, mantle cell lymphoma and indolent lymphomas, such as follicular lymphoma.
The clinical trial is currently open and enrolling patients in a number of centers, including the City of Hope Comprehensive Cancer Center, Duarte, CA, the Medical College of Wisconsin, Milwaukee, Texas Oncology, Austin, Rocky Mountain Cancer Centers, Aurora, CO; and Virginia Cancer Specialists in Fairfax.
As part of the development program, Sutro plans to add more sites later this year.

Tolerability
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.
“The Leukemia & Lymphoma Society is committed to advancing therapies to address critical unmet need,” said Lee Greenberger, Ph.D., The Leukemia & Lymphoma Society 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,” Greenberger added.
“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 for novel targeted therapies,” said Sutro’s CEO Bill Newell.
“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,” Newell added.
“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,” added Dr. Arturo Molina, a medical oncologist and Sutro’s chief medical officer.
Preclinical research
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 vitro cytotoxicity in multiple B-cell tumor cell lines and its anti-tumor activity in multiple myeloma and lymphoma xenograft models.
Proprietary Cell-Free Platform
STRO-001 was developed with Sutro’s XpressCFTM and XpressCF+TM 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.
“With XpressCF+TM, 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,” Trevor Hallam, MD, Sutro’s chief scientific officer noted.
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,” Hallam concluded.
Last Editorial Review: August 13, 2018
Featured Image: Test tubes in clinic, pharmacy and medical research laboratory with scientist using pipette. Courtesy: © 2017 – 2018. Fotolia. Used with permission. Photo 1.0. William Newell, chief executive officer of Sutro Biopharma. Courtesy: © 2017 – 2018. Sutro Biopharma. Used with permission.
Copyright © 2017 InPress Media Group. All rights reserved. Republication or redistribution of InPress Media Group content, including by framing or similar means, is expressly prohibited without the prior written consent of InPress Media Group. InPress Media Group shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon. ADC Review / Journal of Antibody-drug Conjugates is a registered trademarks and trademarks of InPress Media Group around the world.