Highly functional HBV-specific T cells within our immune system are believed to be required for long-term HBV viral control. However, HBV-specific T cells become functionally defective, and reduced in number during chronic HBV infection. One approach to boost HBV-specific T cells is to block the PD-1/PD-L1 protein-protein interaction that is one of the causes of T cell immune disfunction.
Through our comprehensive research, we have identified a class of small molecule oral PD-L1 inhibitors that we believe will allow for controlled checkpoint blockade, enable oral dosing and mitigate systemic safety issues typically seen with checkpoint antibody therapies. We have commenced IND-enabling studies with an oral PD-L1 inhibitor that could potentially be an important part of a combination therapy for the treatment of HBV.