PolyTherics will be working with Canadian drug delivery firm Alpha Cancer Technologies (ACT) in a collaboration where it will use its ThioBridge™ technology to produce alpha fetoprotein (AFP) drug conjugates for ACT to test. Per the deal, PolyTherics will conjugate AFP to a derivative of a cytotoxic drug and, using ThioBridge, produce a range of drug conjugates for testing.
ACT brings to the table its targeted drug delivery system based on AFP, a shuttle protein that binds to AFP receptors, which the Canadian firm says are present in large amounts on most cancer cells but only rarely on healthy cells. AFP reportedly has been shown to be safe in Phase I and II trials. ACT adds that its lead candidate ACT-901, which is currently in preclinical development, will use AFP to deliver paclitaxel to ovarian tumors.
PolyTherics, which is a subsidiary of Abzena, says it developed ThioBridge for site-specific conjugation of cytotoxic payloads to disulfide bonds in proteins and antibodies to provide more stable and less heterogeneous drug conjugates. ThioBridge has been the subject of several other collaborations, including one with Biotecnol going back to 2012 to develop multispecific anticancer Tribody-drug conjugates, and another with MacroGenics, which was extended just last month after ThioBridge was successfully used in a 2013 research program to conjugate a cytotoxic payload to a range of DART antibodies.
ACT CEO Igor Sherman said in a statement that he believes ThioBridge “represents an exceptional strategic fit for ACT in our efforts to bring forward targeted cancer treatments, which have the potential to significantly improve cancer care for many patients.”