SLV-2436 is a highly potent and ATP-competitive inhibitor of MNK1 and MNK2 with IC50s of 10.8 nM and 5.4 nM, respectively.
To confirm the kinome selectivity of SLV-2436 (SEL201), the broad KINOMEscan competitive binding assay is performed at 1 μM, which includes 450 distinct kinases. The observed binding profile for SLV-2436 is significantly concentrated in the CAMK family of kinases that comprises MNK1 and MNK2. SLV-2436-treated KIT-mutant melanoma cells have lower oncogenicity and reduced metastatic ability[1].
To investigate the pharmacodynamic properties of SLV-2436 (SEL201), 5 consecutive oral doses of 10, 25, and 50 mg/kg are administered to mice every 12 hours (twice-daily schedule). At the 10 mg/kg twice-daily dosage, 4 hours after the fifth administration, a low plasma concentration of 125 ng/mL SLV-2436 is determined. However, dosing at 25 and 50 mg/kg twice daily, equivalent to 50 and 100 mg/kg/d of SLV-2436, yields substantially increased dose-dependent plasma exposure, reaching an average level of 1,299 ng/mL and 2,075 ng/mL, respectively. At the 24-hour time point, SLV-2436 is still detectable in the plasma, with dose-dependent concentrations of 9, 73, and 124 ng/mL in the 10, 25, and 50 mg/kg twice-daily treatment groups. Oral (p.o.) administration of SLV-2436 at the dosage of 50 mg/kg twice daily, that is, 100 mg/kg/d, for 37 days is well tolerated in mice[1].
[1]. Zhan Y, et al. MNK1/2 inhibition limits oncogenicity and metastasis of KIT-mutant melanoma. J Clin Invest. 2017 Nov 1;127(11):4179-4192.