biological activity | Bimiralisib (PQR309) is a new type of PI3K/mTOR dual inhibitor that can penetrate into the brain and has anti-lymphoma activity in vitro and in vivo. Compared with other PI3K-related lipid kinase, protein kinase and non-related targets, it has higher selectivity for PI3K/mTOR. |
target | TargetValue PI3Kα (Cell-free say) 1.5 nM (KD) PI3Kβ (Cell-free say) 11 nM (KD) mTOR (Cell-free say) 12 nM (KD) PI3Kγ (Cell-free say) 25 nM (KD) PI3Kδ (Cell-free say) 25 nM (KD) |
Target | Value |
PI3Kα
(Cell-free assay)
| 1.5 nM(Kd) |
PI3Kβ
(Cell-free assay)
| 11 nM(Kd) |
mTOR
(Cell-free assay)
| 12 nM(Kd) |
PI3Kγ
(Cell-free assay)
| 25 nM(Kd) |
PI3Kδ
(Cell-free assay)
| 25 nM(Kd) |
in vitro study | in most of the lymphoma cell lines detected, PQR309 has effective activity with an average IC50 of 233 nM(95% CI, 174-324 nmol/L). Its arrest of cell proliferation is mainly due to cell cycle arrest, which blocks cells in G1 phase, rather than through the apoptosis pathway. PQR309 is more active in B- cell lymphoma cells (such as DLBCL, MCL, CLL and SMZL) than in T-cell-derived ALCL. In lymphoma cell lines, PQR309 inhibited PI3K/mTOR signaling. PQR309 has anti-lymphoma activity in vitro and in vivo, whether given as a single agent or in combination with other drugs. |
in vivo studies | in mice, rats and dogs, PQR309 has oral biological activity, can cross the blood-brain barrier and has good pharmacokinetic parameters. PQR309 had minimal clearance when exposed to rat, dog and human liver microsomes. However, PQR309 was updated quickly in mouse liver microsomes, and 40% compounds were eliminated within 30 minutes. In female mice, the plasma concentration of PQR309 depends on the route of drug administration: the drug half-life of the oral route of administration is about 13-36 minutes, and the drug half-life of the intravenous route is 9-10 minutes. PQR309 has good oral bioavailability (>50%). The male beagle was given 10 mg/kg orally, and the blood concentration peak (Cmax) was 583 ng/ml 60-90 minutes after administration, the half-life was more than 7 hours, and the blood concentration was about 150 ng/ml after 24 hours. PQR309 has an oral bioavailability of 23% in male beagles. In three animal models (Sprague-Dawley rats, CD-1 mice and Beagle dog),PQR309 can be quickly absorbed and has good oral bioavailability. PQR309 has anti-tumor proliferative activity in both PC3 prostate cancer cells and rat PC3 transplanted tumor models. |