BB-Cl-Amidine hydrochloride is an inhibitor of peptidylarginine deminase (PAD) [1].

Treatment with BB-Cl-amidine modestly reduces splenomegaly in MRL/lpr mice and trends towards an increase in circulating anti-NET antibodies when treated with PAD inhibitors. However, PAD inhibitors do not impact body weight or total IgG levels. Notably, both Cl-amidine and BB-Cl-amidine treatments significantly enhance endothelium-dependent vasorelaxation, with BB-Cl-amidine also displaying a pronounced trend towards IRG downregulation. Furthermore, either compound significantly ameliorates muzzle alopecia, often preventing it entirely. This study involved subcutaneous injection of 1 mg/kg doses administered daily to MRL/lpr mice aged 8 to 14 weeks, resulting in markedly improved vasorelaxation and a strong IRG downregulation trend.