Ambrx and Fabrus are joining forces to discover antibodies with properties that are optimized for use as antibody-drug conjugates. Fabrus will use its antibody library, screening, and functional maturation approaches to deliver unique, affinity-matured antibodies against a number of targets nominated by Ambrx.
The collaboration antibodies will be modified by Ambrx, using its unnatural amino acid technology, to produce antibody-drug conjugates directed to each therapeutic target. The agreement grants Ambrx the exclusive right to commercialize conjugated forms of the antibodies generated under the collaboration.
Fabrus will receive various up-front payments and is eligible to receive success fees and a share of certain payments received by Ambrx in the future. Ambrx also has an option to acquire a minority equity interest in Fabrus.
Using synthetic biology and automated parallel fermentation/purification technology, Fabrus says that it has generated over 10,000 highly pure human germline Fab fragments in spatially addressed format. This library is analogous to a combinatorial chemistry library, where the sequence of every position is known, and structure-activity-relationships can be obtained upon screening. The composition of the library is based on known V(D)J gene segments that encode the naïve human repertoire. Iterative library creation and screening allows functional optimization.
Ambrx has two antibody-drug conjugates in its pipeline, both in the preclinical phase. One is being developed for oncology, while the other has an undisclosed target and is partnered with Pfizer.