Rosiptor is an activator of SH2-containing inositol-5'-phosphatase 1 (SHIP1).

Rosiptor is a small-molecule SHIP1 activator.The activating effect of Rosiptor on SHIP1 is 28% at 100 μM in the native enzyme but no effect of Rosiptor is observed when the SHIP1δC2 enzyme is used. Rosiptor induces a concentration-dependent decrease in Akt phosphorylation in MOLT-4 cells, while it fails to affect Akt phosphorylation in Jurkat cells. At 0.1 μM Rosiptor the inhibition amounts to an average of 34%, while at 10 μM the inhibition amounts to an average of 82% in two independent experiments. Rosiptor also induces a concentration-dependent decrease in the production of multiple pro-inflammatory mediators in this system, without affecting cell viability. Rosiptor dose dependently inhibits chemotaxis of most cell types at low micromolar concentrations independent of the chemotactic stimulus[1].

In female Sprague-Dawley rats, the single-dose pharmacokinetics of Rosiptor show that the increases in maximal plasma concentration (Cmax) and AUC0-∞ are dose-proportional at the lower end of the dosing regimen and greater than dose proportional at the higher doses. The oral bioavailability of Rosiptor in rats is 66 and 85% at 10 and 30 mg/kg respectively. Oral bioavailability of Rosiptor in dogs is 88 and 104% at 10 and 30 mg/kg respectively. High tissue concentrations of Rosiptor are detected, as compared to plasma concentrations, at each time point studied[1].

[1]. Stenton GR, et al. Characterization of AQX-1125, a small-molecule SHIP1 activator: Part 1. Effects on inflammatory cell activation and chemotaxis in vitro and pharmacokinetic characterization in vivo. Br J Pharmacol. 2013 Mar;168(6):1506-18.