Discovery of SHR5133, a Highly Potent and Novel HBV Capsid Assembly Modulator

Capsid assembly modulators (CpAMs) represent a new class of antivirals targeting hepatitis B virus (HBV) core protein to disrupt the assembly process. In this work, a novel chemotype featuring a fused heterocycle amide was discovered through pharmacophore exploration. Lead optimization resulted in compound 8 with an EC₅₀ value of 511 nM, and then methyl substitution on the piperazine was found to improve the in vitro potency remarkably. Further SAR studies established the key compound SHR5133, which showed high in vitro antiviral potency, favorable pharmacokinetic profiles across species, and robust in vivo efficacy.