EC50: 2 nM for caspase activation

MPI-0441138 is an inducer of apoptosis and growth inhibition.

Apoptosis or programmed cell death is a process that organisms use to eliminate excessive cells and to control cell numbers. Caspases, a family of cysteine proteases, plays a critical role for the initiation as well as execution of apoptosis.

In vitro: MPI-0441138 was identified as a highly active inducer of apoptosis and as a potent inhibitor of cell proliferation in T47D cells. MPI-0441138 also inhibited tubulin polymerization and was effective in cells overexpressing ABC transporter Pgp-1. It was found that the methyl group on the nitrogen linker was critical for the apoptosis-inducing activity [1].

In vivo: MPI-0441138 could inhibit tumor growth dose-dependently and produced >95% tumor growth inhibition with once weekly dosing at 10 mg/kg and was well tolerated. The maximum tolerated dose of MPI-0441138 was determined to be 25 mg/kg when dosed once weekly, resulting in a good therapeutic index of 2.5. In addition, MPI-0441138 at a dose of 2.5 mg/kg could produce 90% tumor growth inhibition in the MX-1 model when dosed once every day for 5 days for 2 weeks. Furthermore, in nude mice, MPI-0441138 significantly inhibited the growth of human PC-3 prostate cancer xenografts [1].

Clinical trial: Up to now, MPI-0441138 is still in the preclinical development stage.