PB28

PB28 is a preclinical **small-molecule** cyclohexylpiperazine sigma receptor ligand used primarily as an academic research compound rather than a commercially developed therapeutic. It has been described as a high-affinity **sigma-2 receptor agonist** and **sigma-1 receptor antagonist**, with reported nanomolar affinity for both receptor classes. In published laboratory studies, PB28 has shown **antitumor activity** in breast cancer models, including inhibition of cell growth, induction of caspase-independent apoptosis, and modulation of P-glycoprotein that can enhance anthracycline activity. It has also shown **in vitro antiviral activity against SARS-CoV-2**. No human clinical development, approved indication, commercial brand name, or clearly identified sponsoring company is established from the provided context, and the compound appears to remain a noncommercial preclinical research agent.

Other names

PB28PB-28PB 28