Analytical method stability testing

The other reasons for disharmony of the content is the fact that the three major pharmacopoeias are different in terms of monographs and methods required, with the consequence that industry is forced to duplicate testing and generate different specifications, analytical testing, validation of methods, stability testing and summaries. In order to harmonise General... 

For validating analytical methods for testing stability samples, the following elements need to be considered accuracy, precision, linearity, range, specificity, robustness, and detection and quantitation limits. Each of these terms is defined and discussed below. 

This system includes measures and activities related to laboratory procedures, testing, analytical methods development and validation or verification, and the stability program. 

The choice of reaction medium is important and the most important criteria that must be complied with are (i) unreactivity towards reactants and products, (ii) a large range between the melting and boiling points, (iii) good chemical and thermal stability, (iv) compatibility with the analytical methods used to test the reaction, and (v) good solubility of the reactants, and sometimes of products, even if excellent results can be obtained in the heterogeneous phase. 

Use of thermal stability tests (DTA s) to determine the heat sensitivity of a given process mixture is desirable. Recent advances in analytical methods permit good calorimetric determination of heat of reaction. Heat of reaction data are critical for exothermic reactor vent sizing. Heat impact from fire is usually small in comparison, but should not be neglected. 

The validation process begun in Phase I is extended during Phase II. In this phase, selectivity is investigated using various batches of drugs, available impurities, excipients, and samples from stability studies. Accuracy should be determined using at least three levels of concentration, and the intermediate precision and the quantitation limit should be tested. For quality assurance evaluation of the analysis results, control charts can be used, such as the Shewart-charts, the R-charts, or the Cusum-charts. In this phase, the analytical method is refined for routine use. 

Laboratory Control System This includes laboratory test methods, stability program, and analytical method validation. 

Final methods are developed for transfer to operational quality control (QC) laboratories for the release testing of production batches. Additionally, the methods are intended to be applied during Registration Stability studies and for the release of the DP or DS validation batches during the pre-approval development stage. The analytical methods should last for the entire product lifetime therefore, the aim of final method development is to generate fast, robust, reliable, and transferable HPLC methods (preferably isocratic and at low cost). 

Analytical data generated in a testing laboratory are generally used for development, release, stability, or pharmacokinetic studies. Regardless of what the data are required for, the analytical method must be able to provide reliable data. Method validation (Chapter 7) is the demonstration that an analytical procedure is suitable for its intended use. During the validation, data are collected to show that the method meets requirements for accuracy, precision, specificity, detection limit, quantitation limit, linearity, range, and robustness. These characteristics are those recommended by the ICH and will be discussed first. 

Reliable quality control in the field of pharmaceutical analysis is based on the use of valid analytical methods. For this reason, any analytical procedures proposed for a particular active pharmaceutical ingredient and its corresponding dosage forms shonld be validated to demonstrate that they are scientifically sonnd nnder the experimental conditions intended to be used. Since dissolntion data reflect drng prod-net stability and quality, the HPLC method used in snch tests shonld be validated in terms of accuracy, precision, sensitivity, specificity, rngged-ness, and robustness as per ICH guidelines. 

Apart from the qualification dossiers provided by vendors there seems, at present, to be very little information published on the performance of an operational qualification for capillary electrophoresis (CE) instruments other than a chapter in Analytical Method Validation and Instrument Performance. The chapter, written by Nichole E. Baryla of Eli Lilly Canada, Inc, discusses the various functions (injection, separation, and detection) within the instrument and provides guidance on the type of tests, including suggested acceptance criteria, that may be performed to ensure the correct working of the instrument. These include injection reproducibility and linearity, temperature and voltage stability, detector accuracy, linearity, and noise. 

Bofors Analytical Methods for Powders and Explosives , A.B. Bofors, Nobel-krut, Bofors, Sweden (I960), pp 22-30 (Physical methods of examination) 41-62 (Stability tests) 63-5 (Explosive character tests)... 

Initially, tests were performed to determine the LAQL for each analyte. The long-term stability of each sorbed analyte at its LAQL was also determined. Finally, the accuracy and precision of the analytical method alone and also the overall accuracy and precision of the combined sampling and analytical methods were determined. All tests were performed with the previously developed analytical procedures and sampling devices. 

The analytical method had to be previously developed and tested for items such as sample collection efficiency, recovery, and sample stability. 

The stress studies should demonstrate that impurities and degradants from the active ingredient do not interfere with the quantitation of the API [12]. Stress testing of the API, in addition to validating the stability-indicating power of the analytical method, can also help establish the degradation pathways and the intrinsic stability of the molecule [7]. 

PQ should be performed on a daily basis or whenever the instrument is used. The test frequency not only depends on the stability of the equipment but on everything in the system that may contribute to the results. For a liquid chromatograph, this may be the chromatographic column or a detector s lamp. The test criteria and frequency should be determined during the development and validation of the analytical method. 

The key elements of an inspection are to ensure that the facility is capable of fulfilling the application commitments to manufacture, process, control, package, and label a drug product following GMP the adequacy and accuracy of analytical methods submitted, to ensure that these methods are proper for the testing proposed correlation between the manufacturing process for clinical trial material, bioavailability study material, and stability studies and submitted process that the scientific data support full-scale production procedures and controls that only factual data have been submitted and that the protocols are in place to validate the manufacturing process. 

I Laboratory controls Analytical methods, testing for release component testing and stability testing... 

Outsourcing the development, validation, and performance of analytical methods in recent years has become a popular means to facilitate movement of product through the development process. A recent industry survey reported that the vast majority (86%) of the companies responding say they outsource analytical methods development to contract laboratories. Twenty-five percent of the responding firms indicated that they often or always contract out stability testing on development compounds [37]. There are important criteria to follow in working with contract laboratories to ensure that their methods validation procedures yield results that are consistent with those of the client company [38]. This topic will be discussed later in this chapter. 

Analytical testing (preformulation, stability, product release) is a core component of pharmaceutical operations from early R D through manufacturing of the commercial product. The original analytical methods are usually developed by the pioneer pharmaceutical firm and transferred to the provider. In some cases, the early methods are only preliminary methods and are not sufficiently robust to test the quality of downstream (clinical, commercial, and line extension) products and facility quality practices (cleaning validation). In those situations, the supplier is often asked to develop new methods, and in some cases those methods are transferred back to the client. In either scenario, the transfer of validated analytical methodology consists of the following four main tasks [52] ... 

Cleaning validation protocols should describe the equipment to be cleaned, procedures, materials, acceptance criteria, parameters to be monitored and controlled, and the analytical methods to be employed for testing. Validation of cleaning procedures should reflect equipment to be used for key and final intermediates and APIs. The selection of cleaning procedures to be employed should be based on material solubility and cleaning difficulty. The calculation of residue limits should consider the potency, toxicity, and stability of critical materials. 

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