Copanlisib is an inhibitor of class I phosphoinositide 3-kinase (PI3K) isoforms (IC50s = 0.5, 3.7, 6.4, and 0.7 nM for α, β, γ, and δ, respectively).1 It is weakly active or inactive against numerous other kinases. Copanlisib is effective in vivo when administered intravenously, inhibiting PI3K signaling and inducing tumor regression via apoptosis in xenograft tumors in mice.1,2
1.Liu, N., Rowley, B.R., Bull, C.O., et al.BAY 80-6946 is a highly selective intravenous PI3K inhibitor with potent p110α and p110δ activities in tumor cell lines and xenograft modelsMol. Cancer Ther.12(11)2319-2330(2013) 2.Will, M., Qin, A.C.R., Toy, W., et al.Rapid induction of apoptosis by PI3K inhibitors is dependent upon their transient inhibition of RAS-ERK signalingCancer Discov.4(3)334-347(2014)