We are a clinical-stage biopharmaceutical company with one product candidate in a Phase 1/1b clinical trial, and we are focused on leveraging our proprietary ImmunoTAC technology platform to develop systemically delivered, tissue targeted therapeutics for the treatment of cancer, chronic viral infections, and other serious diseases. Initially, we are applying our platform to create a new class of targeted immuno-oncology agents that direct a myeloid cell activator to the tumor microenvironment (TME) in solid tumors to promote cancer cell killing.

Our lead product candidate, SBT6050, is comprised of a TLR8 agonist linker-payload conjugated to a HER2-directed monoclonal antibody that targets tumors such as certain breast, gastric and non-small cell lung cancers. SBT6050 is currently in a Phase 1/1b clinical trial in patients with advanced or metastatic HER2-expressing solid tumors. In this trial, we have observed changes in pharmacodynamic markers in the first dose cohort, and we anticipate providing an update on interim data from the Phase 1 dose-escalation cohorts in the second half of 2021.

SBT6290 is our second product candidate, expanding on the potential of a TLR8 agonist as a payload. SBT6290 is a TLR8 linker-payload conjugated to a monoclonal antibody that targets Nectin4, which is expressed in certain bladder, triple negative breast, head and neck, and non-small cell lung cancers. We anticipate submitting an investigational new drug application (IND) for SBT6290 in the fourth quarter of 2021.

Our third TLR8 program, SBT8230, is comprised of a TLR8 linker-payload conjugated to an ASGR1 monoclonal antibody that is under development for the treatment of chronic hepatitis B virus infection (cHBV). 

Our ImmunoTAC platform is the result of a focused effort to discover ways to systemically deliver disease-modifying small molecules in a directed fashion to sites of disease. Many potentially promising systemic therapies fail to maximize their therapeutic potential due to toxicities in healthy tissues. Our approach is designed to increase the therapeutic window and avert unacceptable toxicities by directly targeting specific disease sites where our therapeutics are locally active.

(Silverback Therapeutics increased its IPO at pricing: 11.5 million shares at $21, up from 10 million shares at $19 to $20, which were the larger terms in its SEC filing on Dec. 3, 2020. Initially the deal’s size was 7 million shares at $17 to $19.)