A quality evaluation strategy for multi-sourced active pharmaceutical ingredient (API) starting materials.

Establishing appropriate impurity specifications for active pharmaceutical ingredient (API) starting materials is an important component of the commercialization and registration of an API. Multiple sources and routes of manufacture of starting materials and the capability of the API synthetic process for tolerating impurities introduced with starting materials must be understood. A strategy for purity method development and use test evaluation of starting materials to aid in establishing quality requirements is described. Phenyl methyl amino propanol (PMAP), a starting material that may be used for fluoxetine hydrochloride and atomoxetine hydrochloride, is used to illustrate the quality evaluation strategy. Knowledge of actual and potential synthetic routes was used to predict potential impurities and guide purity method development. Multiple analytical methods that were semi-orthogonal in the nature of impurity retention (ion-pairing, ion interaction and hydrophilic interaction chromatographic modes) along with use tests were investigated.

Identification, synthesis and pharmacological activity of moxonidine metabolites.

The metabolism of moxonidine, 4-chloro-N-(4,5-dihydro-1H-imidazol-2-yl)-6-methoxy-2-methyl-5-pyrimidinamine, LY326869, in rats, mice, dogs, and humans has been examined. At least 17 metabolites were identified or tentatively identified in the different species by HPLC, LC/MS and LC/MS/MS. The identities of seven of the major metabolites have been verified by independent synthesis. The metabolites are generally derived from oxidation and conjugation pathways. Oxidation occurred at the imidazolidine ring as well as the methyl at the 2 position of the pyrimidine ring. All seven metabolites were examined in the spontaneously hypertensive rats (3 mg kg(-1), i.v.) for pressure and heart rate. Only one, 2-hydroxymethyl-4-chloro-5-(imidazolidin-2-ylidenimino)-6-methoxypyrimidine, exerted a short-lasting decrease in blood pressure, albeit attenuated in magnitude compared to moxonidine.