Active pharmaceutical ingredient stabilizing

Active Pharmaceutical Ingredients Stability Requirements for Excipients Stability Requirements for Drug Substances (APIs)... 

A written stability-testing programme should be established for active pharmaceutical ingredients. Stability-indicating methods should used. 

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. 

For pharmaceutical scientists, the value in cocrystals would be if such materials would be superior active pharmaceutical ingredients relative to the drug substance itself. This possibility has been studied for the carbamazepine-saccharin cocrystal, where its performance characteristics were compared with the marketed form of carbamazepine [46]. It was learned that the physical and chemical stability of formulations containing the carbamazepine-saccharin cocrystal product were similar to those of carbamazepine in the marketed product, and comparative bioavailability studies demonstrated that the cocrystal was a viable alternative drug substance to the anhydrous drug form used in the conventional solid dose forms. 

Complete Chemistry, Manufacturing, and Control (CMC) information provided, including evidence of purity, stability, toxicology testing, and integrity of active pharmaceutical ingredient (API), placebo, and final product. 

While this is a very positive boundary condition for the development of low-dose formulations, the major drawback of the low-dose formulation range is, as mentioned earlier, the potential exacerbation of chemical instability of active pharmaceutical ingredients. Thus, stabilization techniques are of high interest to the formulator dealing with this formulation space. Specifically, stabilizers from various classes of antioxidants have been applied.23,24 It is obvious that the specific knowledge of potential and actual degradation pathways of the drug will be crucial for the development of stable formulations. 

Formulation design is based on the physical, chemical, and biopharmaceutical properties of a drug substance. A formulation for direct compression is composed of active pharmaceutical ingredients and other inactive ingredients such as fillers, binders, dis-integrants, flow aids, and lubricants. Simplicity is the basis of good formulation design. Minimally, a direct compression tablet formulation must meet requirements for manufacturability, uniformity of dose, physical and chemical stability, appropriate dmg release profiles, and bioavailability. In addition, the formulation must meet many quality standards and special requirements to ensure the efficacy and safety of the product. 

Berry, J., Kline, L. C., Sherwood, J. K., et al. (2004), Influence of the size of micronized active pharmaceutical ingredient on the aerodynamic particle size and stability of a metered dose inhaler, Drug Dev. Ind. Pharm., 30,705-714. 

In Section 8.2, the aim of analysis is emphasized especially for the API (active pharmaceutical ingredient) and the drug product. The workflows and the rationale at major decision points during synthetic processing steps where HPLC can be applied in process development are elaborated upon. For example, a fast method is needed to monitor reaction conversion of two components. However, a more complex method would be needed for stability-indicating purposes where multiple degradation products, synthetic by-products, and excipient peaks need to be resolved from the active pharmaceutical ingredient. 

By the time an active pharmaceutical ingredient (API) is made available to an analytical chemist in the formulation development group, most or all of the physical characteristics of an API has already been studied and the information should be available in some sort of a report from the drug substance group or preformulation group. Some of the key parameters that an analytical chemist in formulation development requires from such a report are the solubility and solution stability. 

Although this is not a new method, several researchers have used this method for removal of solvent from other micronization techniques (e.g., Nanocrystals). Initially, spray drying was used for the removal of solvent from solutions, which caused rapid evaporation of the feed solution and precipitation of the dissolved Active Pharmaceutical Ingredient (API)/Stabilizers. This method. 

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