ACP-5862-d4 is deuterium labeled ACP-5862. ACP-5862 is a major active, circulating, pyrrolidine ring-opened metabolite of Acalabrutinib with an IC50 of 5.0 nM for Bruton tyrosine kinase (BTK). ACP-5862 is a weak time-dependent inactivator of CYP3A4 and C