Drugs stability characteristics

For drug substances and drug products, applications for enantiomers and racemates should include a stereochemically specific identity test and/or a stereochemically selective assay. The choice of control tests should be based on the method of manufacture and stability characteristics and, in the case of the finished product, its composition. 

Data to demonstrate the stability characteristics of both the drug substance and the drug product must be collected. Studies using three different batches of both substance and product in their respective containers/packaging must be conducted. Real-time data should be collected under conditions of temperature and relative humidity in line with the recommended storage. Conditions in different world climatic zones must be taken into consideration for cases where normal environmental... 

The stability of suspensions, emulsions, creams, and ointments is dealt with in other chapters. The unique characteristics of solid-state decomposition processes have been described in reviews by D. C. Monkhouse [79,80] and in the monograph on drug stability by J. T. Carstensen [81]. Baitalow et al. have applied an unconventional approach to the kinetic analysis of solid-state reactions [82], The recently published monograph on solid-state chemistry of drugs also treats this topic in great detail [83],... 

Single Test Compound Clustering with Several Marketed Drugs on the Basis of the Similarity of In Vitro Profile Results Including Human Absorption, Oral Bioavailability, Permeability, Solubility, Log D, and Metabolic Stability Characteristics... 

Chemical instability of medicinal agents may take many forms, because the drugs in use today are of such diverse chemical constitution. Chemically, drug substances are alcohols, phenols, aldehydes, ketones, esters, ethers, acids, salts, alkaloids, glycosides, and others, each with reactive chemical groups having different stability characteristics. Chemically, the most frequently encountered destructive processes involve hydrolysis and oxidation. 

During the early discovery phase, the primary function of stability studies is to determine the stability characteristics of the drug. Knowing these characteristics helps researchers select and design the most satisfactory chemical or molecular entity for the desired pharmaceutical profile and indication. The pharmaceutical profile focus on obtaining... 

Warning Letter Citation. The firm failed to adequately assess the stability characteristics of drug products in that samples representing all container-closure systems used in packaging in a given year are not included in the annual stability program. 

As with the bulk drug substance, spedfications for both enantiopure and racemic chiral drug products should include both a stereochemically spedfic identity test and stereochemically selective assay method. The analytical method to be used should not be arbitrarily chosen to be the same as for the bulk drug but should be chosen on the basis of the composition, method of manufacture, and stability characteristics of the formulation. 

The study of stability is not restricted to looking at degradation of the active . It is prudent to bear in mind that any degradation of a formulation excipient may lead to a change in the drug release characteristics of the formulation. For example lactose, a frequently used excipient, can undergo anomerisation in solution between its a- and p- forms. It is conceivable that this could take place in the solid state in a formulation stored under extreme conditions. This could be studied by LC (Figure 12.13). 

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