CAB-ROR2-ADC in clinical testing for treatment of several solid tumor types

SAN DIEGO, CA – June 28, 2018 – BioAtla, LLC, a global biotechnology company focused on the development of Conditionally Active Biologic (CAB) protein therapeutics, announced today the treatment of the first patient in its clinical trial BA3021-001 for BioAtla’s BA3021, a novel conditionally active ROR2-targeted antibody-drug conjugate (CAB-ROR2-ADC). This is a multi-center, open-label, Phase 1/2 study designed to evaluate the safety, tolerability, pharmacokinetics, immunogenicity and antitumor activity of BA3021 in patients with advanced solid tumors including non-small cell lung cancer (NSCLC), triple negative breast cancer and soft tissue sarcoma. CAB-ROR2-ADC is BioAtla’s second CAB investigational product to enter clinical trials following BA3011, CAB-AXL-ADC in February of this year.


The first patient in the BA3021 clinical study was enrolled and dosed at Sarah Cannon Research Institute at Tennessee Oncology in Nashville, TN under the direction of the principal investigator, Howard A. “Skip” Burris III, MD. Dr. Burris, a recognized leader in clinical oncology, serves as chief medical officer and president of clinical operations at Sarah Cannon. “Innovative advancements in the treatment of cancer include tumor specific activation of therapy and promoting appropriate immune response. Providing access to cutting-edge therapies in clinical trials, such as the BA3021 clinical study, further supports our mission to advance care for cancer patients,” said Dr. Burris.


The ROR2 transmembrane protein tyrosine kinase is an onco-fetal protein that acts as a non-canonical Wnt 5A receptor.  ROR2 is found to be highly expressed during embryonic development and in several important cancer types, and the level of expression in tumors is tightly correlated with patient prognosis.  Recently, ROR2 and its ligand Wnt 5A have been shown to be induced in cancers that are resistant to treatment with immune checkpoint inhibitors such as anti-PD-1 antibody immune therapy suggesting a mechanistic role of this receptor-ligand axis in resistance to standard cancer treatments resulting in relapsing, minimal residual disease.  However, low to moderate levels of expression of ROR2 in multiple normal adult tissues are predicted based on RNA expression, histological analysis and functional studies. To minimize the risk of potential disruption of normal function of ROR2 receptors on normal cells, BioAtla applies its proprietary CAB technology to develop its CAB antibody-drug conjugate (ADC) targeting ROR2 with the intent to activate binding to the ROR2 receptor only in the tumor microenvironment and deliver the toxic payload to the cancerous cells.  The CAB-ROR2-ADC BA3021 is designed to maximize efficacy on ROR2 expressing tumors while minimizing toxicity, leading to better clinical outcomes.  


About Conditionally Active Biologics (CABs)

Conditionally Active Biologic proteins are generated using BioAtla’s proprietary protein discovery, evolution and expression technologies. These proteins can be monoclonal antibodies, enzymes and other proteins designed with functions dependent on changes in microphysiological conditions (e.g., pH level, oxidation, temperature, pressure, presence of certain ions, hydrophobicity and combinations thereof) both outside and inside cells.


Studies have shown that cancerous tumors create highly specific conditions at their site that are not present in normal tissue. These cancerous microenvironments are primarily a result of the well understood unique glycolytic metabolism associated with cancer cells, referred to as the Warburg Effect. CAB proteins are designed to deliver their therapeutic payload and/or recruit the immune response in specific and selected locations and conditions within the body and to be active only in the presence of a particular cellular microenvironment. In addition, the activation is designed to be reversible to repeatedly switch ‘on and off’ should the CAB move from a diseased to a normal cellular microenvironment and vice versa. CABs can be developed in a variety of formats including antibodies, antibody drug conjugates (ADCs), bi-specifics, chimeric antigen receptor T-cells (CAR-Ts) and combination therapies.


About BioAtla, LLC

BioAtla is a global biotechnology company with operations in San Diego, California, and Beijing, China. BioAtla develops novel monoclonal antibody and other protein therapeutic product candidates designed to have more selective targeting, greater efficacy, and more cost-efficient and predictable manufacturing than traditional antibodies.




Richard Waldron

Chief Financial Officer

BioAtla, LLC