QM385 is a potent sepiapterin reductase (SPR) inhibitor with an IC50 of 1.49 nM, which blocks T-cell proliferation and autoimmunity at nanomolar potency and with good oral bioavailability[1]. IC50: 1.49 nM (Sepiapterin reductase)[1]
QM385 effectively inhibits the proliferation of human CD4+ T cells at low doses[1].
[1]. Cronin SJF, et al. The metabolite BH4 controls T cell proliferation in autoimmunity and cancer. Nature. 2018 Nov;563(7732):564-568.