Stability study of tablets containing 20 mg of policosanol as active ingredient

Abstract

The objective of a stability study is to determine the period of time
during which a pharmaceutical drug meets appropiate standards when stored under
defined conditions. The stability studies of tablets containing 20 mg of policosanol,
a new cholesterol lowering drug, were conducted to predict an expiration date and
to search the appearance of putative degradation products. All quality specification
parameters such as colour, moisture content, hardness, disintegration, policosanol
content and microbiological limits of the tablets were done. The content of the
active ingredient was determined by Gas Chromatography, using a validated
analytical method. The effect of drastic treatments such as acid and basic hydrolysis,
oxidative and photolytic degradation as well as thermolysis on such parameters
was studied. In addition, studies under drastic conditions of storage (40 °C and 75 %
R. H.) and under enviromental conditions of storage for climatic zones II and IV
were performed. These studies showed that these tablets are a stable pharmaceutical
formulation, without significant changes on their quality criteria at the conditions
studied. Policosanol content stayed unchanged during all these studies, therefore,
it was not possible to determine an expiration date by kinetic method of Arrhenius
extrapolation. The chromatographic profile of the samples after 9 months of thermal
degradation shows chromatographic
peaks that were identified by Gas
Chromatographic-Mass Spectrometric
analysis, corresponding to the octacosanoyl,
triacontanoyl and hexacosanoyl
esters of palmitate and stearate, being
the only degradation products observed
on these studies.