Detecting falsified oral contraceptives by visual assessment and diffuse reflectance spectroscopy (350–2500 nm): the need for supplementing traditional pharmacopeia techniques and the public health implications

OBJECTIVES: Substandard and falsified pharmaceuticals can present a major health risk, particularly for low- and middle-income countries. In a Sub-Saharan African market, United States Agency for International Development (USAID) staff found an oral contraceptive product (0.15 mg levonorgestrel/0.03 mg ethinyl estradiol) labeled with a logo (and brand name) visually matching one historically used by USAID but purportedly manufactured by an unauthorized source. Additional assessment was conducted to determine if more evidence of falsification was present to better understand the public health impact. STUDY DESIGN: Relative to a control, the suspect sample was assessed visually for tablet features and with United States and International Pharmacopeia methods for levonorgestrel/ethinyl estradiol tablets. Diffuse reflectance spectra (350–2500 nm) were collected to further characterize the sample. RESULTS: Although the suspect sample aligned with pharmacopeia tests, visual examination of tablet characteristics and diffuse reflectance spectroscopy (350–2500 nm) assessments supported the tablets were not the same as control samples, confirming the suspect sample was falsified. These results raised concerns for the overall regulatory oversight available for the market with uncertainty regarding the true clinical bioequivalence levels (although adequate dissolution levels were observed). CONCLUSIONS: Comprehensive characterization of suspect pharmaceuticals from the field can often be required depending on the nature of the sample and can have dramatic implications for understanding the public health risks to the end user within the local market. Simple visual assessment and spectroscopic techniques to screen a sample can help to supplement traditional pharmacopeia approaches. IMPLICATIONS: Proper characterization of suspect pharmaceuticals is necessary to best understand their potential public health impact. Situations can occur where traditional pharmacopeial techniques may not adequately characterize a sample. Visual assessments and diffuse reflectance spectroscopy can be supplemented to provide a more holistic analysis.