The diagnostic accuracy of the hand-held Raman spectrometer for the identification of anti-malarial drugs.

BACKGROUND: There is a need for accurate and field-applicable instruments for the evaluation of the quality of anti-malarial drugs. The aim of this study was to determine the diagnostic accuracy of the NanoRam(®), a handheld Raman spectrometer (RS), to identify anti-malarial drugs. METHODS: In total, 289 anti-malarial drugs collected in a randomized field survey in Gabon were evaluated. The samples were compared with authentic products as supplied by the official manufacturer. To determine the sensitivity and specificity of the handheld NanoRam(®) spectrometer in the identification of anti-malarial drugs, a two-gate reversed-flow design was applied. The standards for reporting of diagnostic accuracy studies (STARD) were followed. The index test was the handheld RS. The reference test standards were thin layer chromatography and high performance liquid chromatography with ultraviolet photo diode array detection. RESULTS: The sensitivity [95% confidence interval (95% CI)] and specificity of the RS to correctly identify an anti-malarial drug were 100% (95% CI 94.9-100%) and 96% (95% CI 92.3-99.0%), respectively. The RS could not differentiate between different batches of the same product or different manufacturers of the same product. Intra-observer agreement for 289 samples was 100%. The average time to conduct the RS was 15 s per sample compared to 45 min per sample for TLC. CONCLUSION: The handheld RS holds promise as an easy-to-use, quick and field-applicable instrument for the evaluation of quality of anti-malarial drugs, potentially empowering pharmacists, drug inspectors and medical regulatory authorities. Trial registration NTR4341 (Dutch Trial Registry).

Assessing the quality of anti-malarial drugs from Gabonese pharmacies using the MiniLab®: a field study.

BACKGROUND: Recent studies alluded to the alarming scale of poor anti-malarial drug quality in malaria-endemic countries, but also illustrated the major geographical gaps in data on anti-malarial drug quality from endemic countries. Data are particularly scarce from Central Africa, although it carries the highest burden of malaria. The aim of this medicine quality field survey was to determine the prevalence of poor-quality anti-malarial drugs in Gabon. METHODS: A field survey of the quality of anti-malarial drugs in Gabonese pharmacies was conducted using the Global Pharma Health Fund Minilab(®) tests, following the Medicine Quality Assessment Reporting Guidelines. Anti-malarial drugs were purchased randomly from selected pharmacies in Gabon. Semi-quantitative thin-layer chromatography (TLC) and disintegration testing were carried out to measure the concentration of active pharmaceutical ingredients (APIs). The samples failing the TLC test were analysed by high-performance liquid chromatography. Following the collection of anti-malarial drugs, a street survey was conducted to understand where people purchase their anti-malarial drugs. RESULTS: A total of 432 samples were purchased from 41 pharmacies in 11 cities/towns in Gabon. The prevalence of poor-quality anti-malarial drugs was 0.5% (95% CI 0.08-1.84%). Two out of 432 samples failed the MiniLab(®) semi-quantitative TLC test, of which a suspected artemether-lumefantrine (AL) sample was classified as falsified and one sulfadoxine-pyrimethamine (SP) sample as substandard. High performance liquid chromatography with ultraviolet photo diode array detection analysis confirmed the absence of APIs in the AL sample, and showed that the SP sample did contain the stated APIs but the amount was half the stated dose. Of the people interviewed, 92% (187/203) purchased their anti-malarial drugs at a pharmacy. CONCLUSION: Using the GPHF Minilab(®), the prevalence of poor-quality anti-malarial drugs is far lower than anticipated. The findings emphasize the need for randomized and robust sampling methods in order to collect representative data on anti-malarial drug quality. TRIAL REGISTRATION: NTR4341 (Dutch Trial Registry).

Rabies antibody response after two intradermal pre-exposure prophylaxis immunizations: An observational cohort study.

BACKGROUND: Rabies is a lethal, but vaccine preventable disease. Vaccination uptake is however hampered by the time-consuming three-dose, 21/28-day schedule. The aim of this study was to examine whether adequate rabies antibody titers are reached after two intradermal (ID) doses of rabies vaccine, with a seven-day window. METHOD: We conducted an observational cohort study with military personnel. A titer was assessed by RFFIT, on the day of the third vaccination, to ensure an adequate rabies antibody response after ID immunization. RESULTS: After this abbreviated two-dose, seven-day ID schedule, seroconversion was reached in 99.3% (427/430) with a geometric mean titer of 7.59 IU/mL (95% CI 7.04-8.17). CONCLUSIONS: Implementation of this two-dose schedule will protect more people against Rabies. Travelers and military personnel under time constraints, who otherwise would remain unvaccinated, can be considered adequately protected after this two-dose schedule. For populations in endemic areas, local application of a two-dose schedule could provide an opportunity to vaccinate more people with less vaccine. Given the paucity of published data, this study adds relevant evidence in support of the new policy (2017) of WHO, concerning a two-dose, seven-day schedule is approved for all healthy individuals.