Details

Autor(en) / Beteiligte

• Bellia, Gaetano Francesco

Titel

Investigation of Chemical Differences in Medications Obtained from Diverse Sources Using Novel Spectroscopic and Statistic Approaches

Ort / Verlag

ProQuest Dissertations & Theses

Erscheinungsjahr

2018

Quelle

ProQuest Dissertations & Theses A&I

Beschreibungen/Notizen

• Generic medications are those medicines manufactured by a pharmaceutical company without a license from the company that has first invented and patented the same drug, when the related patent and other exclusivity rights have expired. Only studies of bioequivalence are requested as requirements to introduce a new generic medication in clinics, making easier and financially attractive for many pharmaceutical companies to participate in this typology of market. Organised criminality is strongly attracted by this market both for the high profitability, and for the high similarity to the production and trafficking of illegal controlled substances associated to the extreme difficulties faced by the law enforcement authorities in effectively investigating the online market, because of its anonymity. A significant paradigm continuously frequented in pharmacology is the confliction between views on generic medications that can be used interchangeably with the original medicines. Several clinical studies conducted in certain medical areas have shown as the generic medications present an overlapping therapeutic equivalence to the original ones. On the contrary, for certain other generics, both pharmacokinetics and pharmacodynamics issue have been reported. Also, in some cases issues on the stability of generics have been raised. Despite the numerous research articles and reviews published on the matter of clinical equivalence among generic and original medications, no study to the scientific community has been presented on an analytical evaluation of the chemical composition of the different generic drugs that could shed some lights on the reason of the different clinical performances reported. The main aim of this research was to develop a non-destructive quick qualitative analytical methodology to be able to discriminate differences in the chemical composition from generic medicines that have been reported not presenting similar therapeutic equivalence in clinical comparison studies, obtained from authorised pharmacies and non-authorised online sellers. From the cardio-vascular area, digoxin (with the related cardiac glycosides digitoxin and digoxigenin) and amlodipine (in its different salts maleate, mesylate and besylate used in therapies). In the gastroenterology area, omeprazole both in its racemic and isomeric forms, have been selected as samples to be analysed. In the antihistamine area, cetirizine, in its racemic and isomeric forms, equally for the same reasons as before, have been considered. As starting analytical approaches, voltammetry, FT-IR, Raman spectroscopies and NMR have been considered and a statistical data analysis approach of the analytical data obtained based on multivariate analysis such as principal component analysis, cross validation, correlation scatter plots and factor loadings has been implemented. This work has matched the aims initially set, generating novel methods of analysis to investigate differences in the chemical composition within different groups of generic medications. This study has led to the creation and interpretation of new knowledge, through a systematic acquisition and understanding of a substantial body of scientific literature and through original research, and adjusting the project design in the light of unforeseen problems, conceptualizing, designing and implementing the research project for the generation of novel knowledge.