Earlier today Sutro Biopharma and Celgene confirmed that the companies decided to refocusing the 2014 immuno-oncology collaboration with on four programs that are advancing through preclinical development. These programs including an antibody-drug conjugate or ADC targeting B-Cell maturation antigen (BCMA) previously disclosed by Celgene. Sutro may also produce both GLP and cGMP material as the BCMA ADC program progresses.
Sutro has pioneered a compelling and unique way of discovering, developing and manufacturing therapeutics focusing primarily next generation cancer therapeutics — antibody drug conjugates, or ADCs, and bispecific antibodies. The process Sutro developped allows the companies scientists to unconstrained by traditional methods of cell-based discovery design and develop targeted medicines by innovating outside the constraints of the cell.
The technology enables Sutro to iteratively discover and test molecules in a rapid cycle of weeks rather than months to rapidly identify the optimal molecule designed for safety and potency.
This unique approach to discovery, without the cell, is also transcending the limitations of biologics manufacturing. Sutro, for example, has the world’s only cGMP cell-free manufacturing facility located in San Carlos, California. This state-of- the-art facility confers an important competitive advantage as the company heads into human clinical trials in 2018.
The programs developed in collaboration with Celgene are in addition to Sutro’s own, proprietary, pipeline which includes STRO-001 and STRO-002, two 2018 investigational new drug (IND) candidates.
STRO-001 is an ADC targeting CD74, a cell surface protein associated with B-cell malignancies, including non-Hodgkin lymphoma and multiple myeloma. The investigational drug is based on Sutro’s lead antibody (SP7219) conjugated to non-cleavable DBCO-maytansinoid linker-warheads with an average drug-antibody ratios (DAR) of 2. 
Recent data, confirming the efficacy of STRO-001, was presented during at the 14th International Conference on Malignant Lymphoma, June 14-16, 2017 in Lugano, Switzerland and at the 22nd Congress of the European Hematology Association, June 23, 2017 in Madrid, Spain.
The second drug is STR0-002, an ADC which targets folate receptor alpha which is overexpressed in platinum-resistant ovarian cancer and other solid tumors.
Other collaborative programs
Under the 2014 collaboration with Merck KGaA Sutro is also advancing six ADC programs
In the 2014 agreement, Celgene had worldwide rights to the first collaboration program to reach IND status. Under the newly modified agreement, Celgene can acquire worldwide rights to a second collaboration program to reach IND status. Sutro will retain U.S. development and commercialization rights, and Celgene will retain ex-U.S. rights, to the next two programs to reach IND status from the four programs. Furthermore, under the revised agreement, Sutro receives an undisclosed amount upon signing of the revised agreement and continues to be entitled to development and regulatory milestone payments and royalties.
To acquire worldwide rights to the second program to reach IND status, Celgene must make payments to Sutro in undisclosed amounts.
In addition, Sutro grants Celgene the right to purchase shares of Sutro stock in a future private financing and a right to purchase shares in a private placement contemporaneous with an initial public offering by Sutro. In conjunction with this revision, the option to acquire Sutro has been terminated along with restrictions from Sutro entering into additional collaborations or accessing the public financial markets.
“Our goal is to continue to build momentum for promising antibody-drug conjugates and bispecific antibodies for immuno-oncology therapeutics developed with Sutro’s cell-free protein synthesis platform,” Sutro CEO Bill Newell said.
“With this revised agreement, Celgene continues to support Sutro’s development, while we can move rapidly into development of multiple product candidates and evaluate new opportunities for partnerships and funding,” Newell added.