Ascletis Pharma starts phase-2a of PD-L1 in HBV: https://www.prnewswire.com/news-releases/first-hbv-patient-dosed-in-phase-iia-clinical-trial-of-asc22-a-subcutaneously-administered-pd-l1-antibody-301112931.html As T cell exhaustion in chronic HBV infections is an important factor in immune tolerance, blocking the PD-1/PD-L1 pathway could be an effective immunotherapy approach to improve specific T cell function and lead to an effective clinical cure for chronic hepatitis B. The trial listing is at: https://www.clinicaltrials.gov/ct2/show/NCT04465890 .