Usefulness of medicine screening tools in the frame of pharmaceutical post-marketing surveillance

Abstract

The negative consequences of Substandard and falsified (SF) medicines are widely documented nowadays and there is still an urgent need to find them in more efficient ways. Several screening tools have been developed for this purpose recently. In this study, three screening tools were used on 292 samples of ciprofloxacin and metronidazole collected in Cameroon. Each sample was then analyzed by HPLC and disintegration tests. Seven additional samples from the nitro-imidazole (secnidazole, ornidazole, tinidazole) and the fluoroquinolone (levofloxacin, ofloxacin, norfloxacin, moxifloxacin) families were analyzed to mimic falsified medicines. Placebo samples that contained only inert excipients were also tested to mimic falsified samples without active pharmaceutical ingredient (API). The three screening tools implemented were: a simplified visual inspection checklist, a low-cost handheld near infrared (NIR) spectrophotometer and paper analytical devices (PADs). Overall, 61.1% of the samples that failed disintegration and assay tests also failed the visual inspection checklist test. For the handheld NIR, one-class classifier models were built to detect the presence of ciprofloxacin and metronidazole, respectively. The APIs were correctly identified in all the samples with sensitivities and specificities of 100%. However, the importance of a representative and up-to-date spectral database was underlined by comparing models built with different calibration set spanning different variability spaces. The PADs were used only on ciprofloxacin samples and detected the API in all samples in which the presence of ciprofloxacin was confirmed by HPLC. However, these PADs were not specific to ciprofloxacin since they reacted like ciprofloxacin to other fluoroquinolone compounds. The advantages and drawbacks of each screening tool were highlighted. They are promising means in the frame of early detection of SF medicines and they can increase the speed of decision about SF medicines in the context of pharmaceutical post-marketing surveillance.

A randomised survey of the quality of antibiotics and other essential medicines in Indonesia, with volume-adjusted estimates of the prevalence of substandard medicines

“…It underlines the need for more affordable medicine testing technologies, as well as greater attention to impurities and non-active ingredients in considering the quality of medicines. [56][57][58] Its limitations notwithstanding, our study remains one of the most comprehensive single-country academic surveys of medicine quality. And yet we underline that the field survey data imperfectly reflect the prevalence of out of specification products in the market, or their true threat to public health.…”

In-Field Implementation of Near-Infrared Quantitative Methods for Analysis of Medicines in Tropical Environments

“…), and the need for representative data sets for the calibration of the models. 23,24 On the other hand, a quantitative approach using NIR handheld devices can be useful for near-site analysis of a large number of samples. This screening step enables a wiser allocation of resources.…”