BioAtla® Receives Broad Patent Covering Conditionally Active Biologics

April 30, 2014

Proprietary "Smart Antibodies" Allow for Selective Activation in Cancerous Tissues

San Diego, Calif. - April 30, 2014 - BioAtla©, a global biotechnology company focused on the development of differentiated biological therapeutics, today announced that the United States Patent and Trademark Office (USPTO) has issued to BioAtla©U.S. Patent No. 8,709,755, its first patent directed to methods of generating conditionally active antibodies.  Conditionally active antibodies are discovered using sophisticated protein evolution technologies for generating therapeutics that are activated in selected microenvironments within the body, such as those indicative of cancerous tumors.   BioAtla©'s patent covers method-independent approaches of evolving these conditionally active antibodies, thereby providing a novel mechanism for antibody selectivity.

"BioAtla©'s Conditionally Active Biologics (CABs) antibody platform represents a disruptive technology for the development of a powerful new class of immunotherapeutics," said Jay M. Short, Ph.D., president, chief executive officer and chairman of the board of BioAtla©. "CABs can be designed to target specific tissues in cancerous or distressed conditions associated with unique microenvironments in the body.  Most importantly, our technology increases the number of possible tumor targets, improves the selectivity of existing targets, enhances therapeutic safety and enables increased potency of antibody therapeutics by expanding the opportunity to use antibody drug conjugates."

"BioAtla©'s new platform is an important extension of its proprietary protein evolution capabilities that the company has been developing and applying to drug discovery and development for many years. Our first partnered proprietary CAB in development is an anti-tumor compound targeting the KRAS-positive cancers including colorectal, pancreatic and non-small cell lung cancers. The CAB discovery platform promises several novel product candidates and unprecedented "biobetter" antibodies as our strategic direction expands to include developing highly differentiated compounds for our internal pipeline, as well as for our partners. Advancing this class of smart therapeutics offers the hope of new cures for treating devastating, currently untreatable cancers." Dr. Short continued.

About Conditionally Active Biologics (CABs)

Conditionally Active Biologic proteins (CABs) are generated using BioAtla©'s proprietary protein evolution technologies that typically employ uniquely selected amino acid substitutions in a protein that work together to confer selective conditional activation. These proteins can be monoclonal antibodies (mAbs) or enzymes designed with functions dependent on changes in microphysiological conditions (e.g., pH level, oxidation, temperature, pressure, presence of certain ions, hydrophobicity and combinations thereof).

Studies have shown that cancerous tumors create highly specific conditions at their site that are not present in normal tissue. These cancerous microenvironments are a result of the well understood unique glycolytic metabolism associated with cancer cells, referred to as the Warburg Effect, which was first identified in the 1920's and is the basis of the widely-used PET scan cancer detection method today. CAB-designed mAbs can be programmed to deliver their therapeutic payload and/or recruit the immune response in specific and selected locations and conditions within the body. CABs increase safety because the drug is activated when it preferentially binds directly to its intended target protein in the area of disease. In this example, the CAB does not effectively bind to the same protein located in healthy tissue or other part of the body that otherwise results in undesirable toxicity.

CABs allow for higher dosing, the development of effective, non-immunogenic drugs, and the use of targets that are validated for cancer cells but traditionally considered too prevalent among normal cells to be used safely in current drug therapies. This opens a potentially rich range of targets for CABs that cannot be addressed using existing technologies. CABs may also be employed as diagnostic tools to reveal and pinpoint conditions indicative of cancerous activity.