Pharmaceutical development and technology

Ethyl methanesulphonate in a parenteral formulation of BMS-214662 mesylate, a selective farnesyltransferase inhibitor: formation and rate of hydrolysis.

PMID 19883257


The objectives of the present study were to investigate the formation and rate of hydrolysis of ethyl methanesulphonate (EMS) in BMS-214662 mesylate drug substance and parenteral formulation by a gas chromatographic/mass spectrometric (GC/MS) method. EMS levels in the drug substance ranged between 0.3 microg/g and 0.8 microg/g. The parenteral formulation contains ethanol and the reaction between residual free methane sulphonic acid and ethanol may lead to the formation of EMS. Given that EMS is a potent mutagen, it is therefore of vital importance to eliminate or reduce the risk of human exposure. Data indicate no significant increase in the levels of EMS following storage of the drug product for 18 weeks at 25 degrees C or six weeks at 60 degrees C indicating that the potential reaction between ethanol and free methane sulphonic acid may not occur in the BMS-214662 formulation under the storage conditions evaluated and therefore causes no plausible safety concerns of EMS exposure in humans. Kinetic studies were conducted by spiking 200 ppb of EMS into water and the diluted and undiluted parenteral formulation. The rates of hydrolysis of EMS at 25 degrees C followed pseudo-first order kinetics and were determined to be 2.35 x 10(-4)min(-1), 67.4 x 10(-4)min(-1), and 1.32 x 10(-4)min(-1) in water, undiluted, and diluted drug product, respectively.