BIO5192 hydrate is a selective and potent integrin α4β1 (VLA-4) inhibitor (Kd<10 pM). BIO5192 hydrate selectively binds to α4β1 (IC50=1.8 nM) over a range of other integrins. BIO5192 hydrate results in a 30-fold increase in mobilization of murine hematopoietic stem and progenitors (HSPCs) over basal levels[1][2]. The combination of BIO5192 hydrate (1 mg kg; i.v.) and Plerixafor (5 mg kg; s.c.) exert an additive effect on progenitor mobilization[1].BIO5192 hydrate (30 mg kg; s.c; bid; during days 5 through 14) delays paralysis associated with EAE (experimental autoimmune encephalomyelitis)[2].BIO5192 hydrate (1 mg kg, i.v.) shows the terminal half-life is 1.1 hours. BIO5192 hydrate (3, 10, and 30 mg kg; s.c.) shows half-lives of 1.7, 2.7, and 4.7 hours, respectively. The blood plasma curves show that the AUC for the s.c. route of administration increased about 2.5-fold from 5,460 h*ng ml for the 3 mg kg dose to 14,175 h*ng ml for the 30 mg kg[1]. Animal Model: C57BL 6J x 129Sv J F1 mice[1] [1]. Ramirez P, et al. BIO5192, a small molecule inhibitor of VLA-4, mobilizes hematopoietic stem and progenitor cells. Blood. 2009;114(7):1340‐1343. [2]. Leone DR, et al. An assessment of the mechanistic differences between two integrin alpha 4 beta 1 inhibitors, the monoclonal antibody TA-2 and the small molecule BIO5192, in rat experimental autoimmune encephalomyelitis. J Pharmacol Exp Ther. 2003;305(3):1150-1162.
QLT0267 is an inhibitor targeting integrin-linked kinase (ILK; IC50= 26 nM), showing over 10-fold selectivity against cyclin-dependent kinases 1, 2, and 5 (Cdk1, Cdk2, and Cdk5), and over 1,000-fold selectivity against C-terminal Src kinase (CSK), DNA-PK, Pim-1, Akt, PKC, and casein kinase 2 (CK2) at a concentration of 10 mg/ml. This compound effectively inhibits the proliferation of NPA187 papillary thyroid cancer cells with an IC50 of approximately 3 µM and induces apoptosis in NPA187, DRO, and K4 cancer cell lines. In vivo studies reveal that QLT0267, administered at 100 mg/kg, significantly reduces tumor growth in a DRO mouse xenograft model and diminishes both tumor volume and intratumoral vascularization in a U87MG glioblastoma mouse xenograft model, showcasing its potential for therapeutic applications in cancer treatment.
Echistatin TFA, the smallest active RGD protein belonging to the family of disintegrins that are derived from snake venoms, is a potent inhibitor of platelet aggregation. Echistatin is a potent inhibitor of bone resorption in culture. Echistatin is a potent antagonist of αIIbβ3, αvβ3 and α5β1[1][2][3][4]. [1]. J Musial, et al. Inhibition of platelet adhesion to surfaces of extracorporeal circuits by disintegrins. RGD-containing peptides from viper venoms. Circulation. 1990 Jul;82(1):261-73.[2]. M Sato, et al. Echistatin is a potent inhibitor of bone resorption in culture. J Cell Biol. 1990 Oct;111(4):1713-23.[3]. C C Kumar, et al. Biochemical characterization of the binding of echistatin to integrin alphavbeta3 receptor. J Pharmacol Exp Ther. 1997 Nov;283(2):843-53.[4]. I Wierzbicka-Patynowski, et al. Structural requirements of echistatin for the recognition of alpha(v)beta(3) and alpha(5)beta(1) integrins. J Biol Chem. 1999 Dec 31;274(53):37809-14.