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Background The influx of substandard and falsified medicines is a global public health challenge and its rapid detection is a key solution to the menace. This study used three screening methods and one confirmatory method for the quality assessment of 25 batches of artemether/lumefantrine dosage forms from the Ghanaian market to test that combined screening methods only can rapidly detect substandard and/or falsified medicines in areas where confirmatory methods may not be available. Methods The quality of artemether/lumefantrine tablet products obtained from pharmacies and licensed chemical seller shops within the Accra metropolis in Ghana were analysed using three screening methods (GPHF Minilab, Colorimetry and Counterfeit Drug Indicator) and one confirmatory method (high-performance liquid chromatography). Results The results showed that 18/25 batches of the artemether/lumefantrine samples passed using the combined screening and confirmatory methods and 5/25 batches of the artemether/lumefantrine samples failed using the combined screening and confirmatory methods. However, 1/25 batch of the artemether/lumefantrine samples failed using the combined screening methods but passed using the confirmatory method. Also, 1/25 batch of the artemether/lumefantrine samples passed using the combined screening methods but failed using the confirmatory method. This notwithstanding, the combined screening methods and the confirmatory method provided equivalent quality assessment profiles for 23/25 (92%) batches of the artemether/lumefantrine tablet products. Out of the 6 samples that failed the confirmatory test, 1/6, 2/6, and 3/6 failed on the high (> 110%), low ( Conclusion The combined screening methods may be used for rapid detection of falsified and/or substandard medicines without using a confirmatory method. However, additional research on the best combinations of screening devices/methods to rapidly detect the quality of medicines is recommended.

Background. Leishmaniasis is a neglected tropical disease caused by the Leishmania parasite and transmitted by the female phlebotomine sandfly. The disease can affect the skin (least fatal) or internal organs (most fatal). Current treatment options for leishmaniasis have a number of adverse effects, and there appears to be resistance by the protozoan parasite (Leishmania spp.). Reports suggest that quinine sulphate, not indicated for leishmaniasis, is effective in killing the Leishmania parasite. Indeed, the efficacy of any drug is dependent on the concentration at the target site, which is also almost dependent on drug formulation. The current study assessed the pharmacokinetic profile of the microparticulate formulation of quinine sulphate and its in vitro and in vivo efficacy against Leishmania donovani. Methods. Quinine sulphate was encapsulated in bovine serum albumin by the spray-drying method. Quinine sulphate microparticles were evaluated for size, zeta potential, drug content, encapsulation efficiency, and in vitro release properties. Afterwards, the pharmacokinetic characteristics of quinine sulphate microparticles were estimated and in vivo efficacy studies were also conducted. Results. The size range of the quinine sulphate microparticles was between 2.0 and 5.0 µm. Microparticles had an average zeta potential of −35.2 mV and an encapsulation efficiency of 94.5%. Also, Cmax, t1/2, and AUC were all significantly desirable for quinine sulphate microparticles compared to the drug powder. Quinine sulphate microparticles significantly reduced parasite load in rat organs than amphotericin B. Conclusion. Overall, quinine sulphate microparticles had better pharmacokinetic profile and showed higher efficacy against Leishmania donovani parasites in vivo. Thus, quinine sulphate microparticles have the potential, especially, in treating visceral leishmaniasis.

The use of excipients with the ability to synergize the action of active pharmaceutical ingredients is highly recommended. Although a large spectrum of surfactants can be used in the preparation of polymeric nanoparticles, the poloxamer surfactants are currently being explored because they have been shown to preferentially target cancer cells as well as inhibit Multi-Drug Resistant proteins and other drug efflux transporters on the surface of cancer cells. The proper type and concentration of surfactant used plays a major role in the stability of the nanosuspensions. The aim of the study was to assess the effect of three different poloxamer surfactant (Pluronic F-108, pluronic F-127 and kolliphor P-188) and chitosan on the stability, immunogenicity, cytotoxicity of dasatinib nanoparticles, as well as cellular uptake of nanoparticles by various cell types. A combination of chitosan and the poloxamers enhanced stability of nanoparticles: average size was 190 ± 20 nm just after preparation, changing to 200 ± 40 nm after 28 days of storage. Uptake of dye-loaded nanoparticles into the cells was 1.5 times more than a solution with an equivalent amount of dye. The uptake of nanoparticles into all the cell lines used was highest for P-188 nanoparticles, whilst F-127 nanoparticles were the least taken up. Poloxamers were observed to be non-toxic to the cells, however, stimulation of cell growth was observed in some cases. The properties exhibited by the various poloxamers in this study could guide in the selection of an appropriate poloxamer for the formulation of nanoparticles.

The aim of this study was to formulate, characterise and evaluate the activity of amodiaquine microparticles against Leishmania donovani. Microparticles were formulated by encapsulating the drug in bovine serum albumin using the spray-dryer method. The microparticles were evaluated for size, zeta potential, drug content, encapsulation efficiency and in vitro release profile. The size range of the microparticles formulated was between 1.9 and 10 μm with an average zeta potential of -25.5 mV. Of the expected 20% drug loading, an average of 18.27% was obtained giving an encapsulation efficiency of 91.35%. Pharmacokinetic profile of amodiaquine improved with microencapsulation of the drug with C

We developed and validated a new analytical method for the simultaneous quantification of artemether and lumefantrine in fixed-dose tablets and powders for reconstitution into pediatric suspensions (PSs). The method showed linearity (r2 > 0.9947), precision (coefficient of variation < 2%), accuracy (deviation of mean from actual concentrations < 4%), and specificity (peak purities > 99%). The validated method was used to analyze 24 batches of fixed-dose tablets and PSs of artemether and lumefantrine. Of the samples, 23 were obtained using convenience sampling of commonly available brands within Accra in Ghana and one was obtained from Aarhus University Hospital. In all, 83.3% (confidence interval: 80–120%) passed for both artemether and lumefantrine contents, 16.7% failed by the U.S. Pharmacopoeia standards, 8.3% failed for one content, and 8.3% failed for both contents. All four products (16.7%) that failed were PSs, and two (8.3%) showed higher levels of artemether than prescribed (222% and 756%). We developed and validated a new analytical method for the simultaneous quantification of artemether and lumefantrine in fixed-dose tablets and powders for reconstitution into pediatric suspensions (PSs). The method showed linearity (r(2) > 0.9947), precision (coefficient of variation < 2%), accuracy (deviation of mean from actual concentrations < 4%), and specificity (peak purities > 99%). The validated method was used to analyze 24 batches of fixed-dose tablets and PSs of artemether and lumefantrine. Of the samples, 23 were obtained using convenience sampling of commonly available brands within Accra in Ghana and one was obtained from Aarhus University Hospital. In all, 83.3% (confidence interval: 80-120%) passed for both artemether and lumefantrine contents, 16.7% failed by the U.S. Pharmacopoeia standards, 8.3% failed for one content, and 8.3% failed for both contents. All four products (16.7%) that failed were PSs, and two (8.3%) showed higher levels of artemether than prescribed (222% and 756%).

Aim: To evaluate in vitro the effectiveness of several anti-infective agents alone and in combination against Leishmania donovani. Method: A convenient stratified sampling method was used to obtain selected anti-infective agents. For individual drug samples, Half Maximal Inhibitory Concentrations (IC50) were obtained using the broth dilution method. The IC50’s of the drugs which were active against L. donovani were used as reference values to prepare drug combinations for the modified microdilution checkerboard method. Results: Five (5) out of the fifty-six (56) drugs used showed activity (inhibition of cell growth) against L. donovani cells. They include Quinine sulphate (IC50 = 0.089 μg/ml), gentamicin (IC50 = 8.1 μg/ml), amodiaquine (IC50 = 138 μg/ml) and the two standard drugs: Amphotericin B (IC50 = 6.3 μg/ml) and Pentamidine (IC50 = 25 μg/ml). The remaining fifty-one (51) drugs did not show any inhibition within the range of concentrations used (1.25 - 160 μg/ml). The drug combinations of Pentamidine/Amodiaquine, Pentamidine/ Quinine sulphate, Pentamidine/Gentamicin, Amphotericin B/Quinine Sulphate, Amphotericin B/ Gentamicin, Amodiaquine/Quinine sulphate and Amodiaquine/Gentamicin showed synergistic effects against L. donovani whereas the Amphotericin B/Amodiaquine combination was antagonistic. Notable in the results obtained was the high effectiveness of quinine sulphate in inhibiting the growth of L. donovani. Quinine sulphate, though not indicated for leishmania treatment, was more effective than the two standard drugs and has a potential of playing a significant role in the treatment of leishmaniasis. Conclusion: This study has revealed five (5) anti-infective agents that by themselves or in combinations show activity against L. donovani. Some of the drug combinations which showed synergism should further be investigated. These results have to be confirmed by in vivo studies to define their roles in leishmaniasis treatment.

The availability of falsified antimalarial drugs can be reduced with effective drug regulatory agencies and proper enforcement. Fundamental to these agencies taking action, rapid identification must be made as soon as they appear in the market place. Since falsified antimalarials occur mostly in developing countries, performing drug analysis presents itself with unique challenges. A fundamental factor in choosing a useful technique is affordability and simplicity. Therefore, we suggest a three-tiered drug evaluation strategy for identifying a falsified drug in resource-poor areas. Tier I is a simple comparison of a tablet's weight and dimensions with official specifications. Tier II uses inexpensive photometric devices (laser and fluorescence) to evaluate a tablet. Suspicious samples from Tier I and II assessments are then subjected to a colorimetric assay for active ingredients identification and quantification. In this article, we evaluate a novel colorimetric assay for the simultaneous assessment of both lumefantrine and artemether in co-formulated Coartem™ tablets, and integrate the method with two novel, low-cost, fluorescence and laser photometric devices. Image analysis software is used for the assessments. Although artemether–lumefantrine is used as an example, the strategy may be adapted to other medicines.

Aim: To evaluate in vitro the effectiveness of several anti-infective agents alone or in combination against Mycobacterium smegmatis. Method: A convenient stratified sampling method was used to obtain selected anti-infective agents. For individual drug samples, Minimum Inhibitory Concentrations (MIC) were obtained using the agar-well plate diffusion technique. Fractional Inhibitory Concentration Indices (FICI) were calculated for drug combinations using their MIC as obtained from the broth dilution method. Results: Of the thirty (30) anti-infective agents analyzed, ten (10) had MIC equivalent to or better than rifampicin (reference TB drug). Seven (7) drugs had MIC higher than rifampicin, while twelve (12) showed no growth inhibition of M. smegmatis. Analysis of the effect of drug combinations on M. smegmatis indicated that four (4) combinations, including rifampicin/ethambutol showed synergism. One (1) was additive, two (2) were indifferent and one (1) combination showed antagonism. Conclusion: Notable in the results obtained was the high effectiveness of the carbapenems in inhibiting the growth of M. smegmatis. Carbapenems, though not indicated for TB treatment, has a potential of playing a significant role in the treatment of tuberculosis. Also the drug combinations which showed synergism, especially those that involved the macrolide antibiotics, should further be investigated. These results have to be confirmed by in vivo clinical studies to define their roles in tuberculosis treatment.

Background: Widespread resistance has been recorded with the use of monotherapy in the management of malaria. In 2000, Ghana initiated the process of using Artemisinin-based combination therapy (ACT) following the World Health Organization’s (WHO) recommendation. Globally and in Ghana, there stands a high risk of development of resistance to the ACTs due to the act of counterfeiting or substandard drugs. In 2009, there was a report that fake Coartem, an ACT had been found in Ghana by the Drug Quality and Information (DQI) Program; this is a serious national problem that needs redress thus the need to conduct this study to check if there are any substandard or counterfeit Artemether/ Lumefantrine tablets on the Ghanaian market. Method: Using Representative sampling method, a total of nine different brands or samples of artemether/lumefantrine tablets were sampled from nine different Pharmacies in Accra. The samples were analyzed using a validated MVHimagePCv8.exe colour software technology. Results: The International Conference on Harmonization (ICH) and United States Pharmacopoeia (USP) recommend that for assay of tablets, the percentage concentration should fall within 80%-120%. After the analysis, seven out of the nine samples passed the test to varying degrees. Two samples (AL-S4 and AL-S6) however failed the test with AL-S4 recording artemether concentration (126.07%) above and Lumefantrine concentration (78.38%) below the recommended figure while AL-S6’s 51.53% failed to meet the minimum allowable concentration for lumefantrine in a tablet. Conclusion: The results presented show that some Artemether/Lumefantrine tablets on the Ghanaian market still have issues with regards to quality or level of active ingredients. There would therefore be the need for further studies to be conducted into these products especially those that failed the test.

The pharmacokinetics of Amphotericin B (AmB) from polyethylene glycol 2000 (PEG 2000) entrapped cross-linked bovine serum albumin (BSA) microsphere formulations were investigated and compared with solution formulation. The microsphere preparations were characterized for particle size using electron microscopy, zeta potential and encapsulation efficiency. The microsphere formulations demonstrated a sustained release of AmB for a longer period of time, with no rise in plasma creatinine and potassium levels. The enhanced AmB accumulation in lungs was observed which could be of importance since lungs are the primary target in most fungal infections. The stealth property of submicron cross-linked BSA microspheres in formulations containing PEG 2000 (formulation F-2N) and without PEG 2000 (formulation F-1N) was also evaluated. There was no evidence that microspheres embedded with PEG remained longer in circulation; however, it was noticed that the internalization of formulation F-2N microspheres was delayed when compared with microspheres from formulation F-1N.

The high performance liquid chromatography method is useful., We developed a colorimetric and chromatographic assay for oseltamivir to assess the authenticity of Tamiflu (F. Hoffmann-La Roche Ltd., Basel, Switzerland) because of a growing concern about counterfeit oseltamivir. The colorimetric assay is quantitative and relies on an extractable colored ion-pair complex of oseltamivir with Congo red or bromochlorophenol blue. The reverse-phase chromatographic assay uses an alkaline mobile phase with UV detection. Both methods were evaluated for variability and selectivity and subsequently applied to batches of oseltamivir products acquired through the Internet. The Congo red test showed greater assay sensitivity, linearity, and accuracy. Colorimetric and chromatographic analysis showed all batches of oseltamivir product were within ±15% of the stated amount of active ingredient.

The proliferation of counterfeit and poor-quality drugs is a major public health problem; especially in developing countries lacking adequate resources to effectively monitor their prevalence. Simple and affordable field methods provide a practical means of rapidly monitoring drug quality in circumstances where more advanced techniques are not available. Therefore, we have evaluated refractometry, colorimetry and a technique combining both processes as simple and accurate field assays to rapidly test the quality of the commonly available antimalarial drugs; artesunate, chloroquine, quinine, and sulfadoxine. Method bias, sensitivity, specificity and accuracy relative to high-performance liquid chromatographic (HPLC) analysis of drugs collected in the Lao PDR were assessed for each technique. The HPLC method for each drug was evaluated in terms of assay variability and accuracy. The accuracy of the combined method ranged from 0.96 to 1.00 for artesunate tablets, chloroquine injectables, quinine capsules, and sulfadoxine tablets while the accuracy was 0.78 for enterically coated chloroquine tablets. These techniques provide a generally accurate, yet simple and affordable means to assess drug quality in resource-poor settings.

Microparticles are widely employed as carriers of biologically active compounds with many possible applications. For targeted drug delivery and sustained release purposes, biopolymers (i.e. polysaccharides and proteins) have been proposed. In this study, microsphere formulations of vancomycin were prepared by the spray-drying method. Bovine serum albumin (BSA) was used as a polymer matrix and was cross-linked with glutaraldehyde after microsphere preparation. The product yield obtained from the spray-drying method was approximately 75%. The mean particle size was 5 +/- 1.6 microm, with the majority of particles between 4 and 8 microm. The extent of cross-linking affected the release of vancomycin from microspheres. Moreover, both rate and extent of vancomycin release from microspheres decreased with increasing glutaraldehyde concentration. Encapsulation of vancomycin did not alter the bioactivity of the drug and it was more effective in killing Staphylococcus aureus than the solution form.

The overall study goal was to produce a microparticle formulation containing atropine sulfate for ocular administration with improved efficacy and lower side effects, compared with that of the standard marketed atropine solution. The objective was to prepare an atropine sulfate-loaded bovine serum albumin-chitosan microparticle that would have longer contact time on the eyes as well as better mydriatic and cycloplegic effect using a rabbit model. The microparticle formulation was prepared by method of spray-drying technique. The percent drug loading and encapsulation efficiency were assessed using a USP (I) dissolution apparatus. The particle sizes and zeta potential were determined using laser scattering technique and the surface morphology of the microparticles was determined using a scanning electron microscope. The product yield was calculated from relative amount of material used. In vitro cytotoxicity and uptake by human corneal epithelial cells were examined using AlamarBlue and confocal microscopy. The effects of the microparticle formulation on mydriasis in comparison with the marketed atropine sulfate solution were evaluated in rabbit eyes. The prepared microparticle formulation had ideal physicochemical characteristics for delivery into the eyes. The in vivo studies showed that the microparticles had superior effects on mydriasis in rabbits than the marketed solutions

Background In vivo efficacy assessments of the first-line treatments for Plasmodium falciparum malaria are essential for ensuring effective case management. In Ethiopia, artemether-lumefantrine (AL) has been the first-line treatment for uncomplicated P. falciparum malaria since 2004. Methods Between October and November 2009, we conducted a 42-day, single arm, open label study of AL for P. falciparum in individuals >6 months of age at two sites in Oromia State, Ethiopia. Eligible patients who had documented P. falciparum mono-infection were enrolled and followed according to the standard 2009 World Health Organization in vivo drug efficacy monitoring protocol. The primary and secondary endpoints were PCR uncorrected and corrected cure rates, as measured by adequate clinical and parasitological response on days 28 and 42, respectively. Results Of 4426 patients tested, 120 with confirmed falciparum malaria were enrolled and treated with AL. Follow-up was completed for 112 patients at day 28 and 104 patients at day 42. There was one late parasitological failure, which was classified as undetermined after genotyping. Uncorrected cure rates at both day 28 and 42 for the per protocol analysis were 99.1% (95% CI 95.1-100.0); corrected cure rates at both day 28 and 42 were 100.0%. Uncorrected cure rates at day 28 and 42 for the intention to treat analysis were 93.3% (95% CI 87.2-97.1) and 86.6% (95% CI 79.1-92.1), respectively, while the corrected cure rates at day 28 and 42 were 94.1% (95% CI 88.2-97.6) and 87.3% (95% CI 79.9-92.7), respectively. Using survival analysis, the unadjusted cure rate was 99.1% and 100.0% adjusted by genotyping for day 28 and 42, respectively. Eight P. falciparum patients (6.7%) presented with Plasmodium vivax infection during follow-up and were excluded from the per protocol analysis. Only one patient had persistent parasitaemia at day 3. No serious adverse events were reported, with cough and nausea/vomiting being the most common adverse events. Conclusions AL remains a highly effective and well-tolerated treatment for uncomplicated falciparum malaria in the study setting after several years of universal access to AL. A high rate of parasitaemia with P. vivax possibly from relapse or new infection was observed. Trial Registration NCT01052584

As multidrug resistance continues to be a problem in cancer treatment, controlled release delivery systems, such as microspheres, may aid to give a slower release of anticancer drugs into drug resistant tumor cells. In this study doxorubicin microspheres microencapsulated in an albumin matrix were prepared via the spray-drying method and characterized for particle size, content analysis, and release studies. They were then evaluated in vitro using drug resistant murine melanoma tumor cells for uptake and efflux studies. Spray-drying produced a dispersed powder with a mean particle size of 4.91 ± 1.2 µm, 60% product yield, and encapsulation efficiency of 85% and a ζ potential range of 37 to -40 mV. Intracellular doxorubicin concentrations were higher in drug resistant tumor cells treated with microspheres as opposed to solution, and efflux of doxorubicin from the tumor cell was inhibited. Greater cytotoxic effects were seen in tumor cells treated with doxorubicin microspheres versus solution up to and after 3 days. In vivo pharmacokinetic studies conducted in male Sprague-Dawley rats, revealed a plasma-level time curve indicative of a two-compartment model, and showed prolonged half-life of doxorubicin, greater area under the plasma concentration time curve, and increased plasma concentrations of doxorubicin in rats at 8 and 24 h after administration of doxorubicin microspheres.

Vancomycin (VCN) is a glycopeptide antibiotic that is effective in the treatment of gram-positive bacterial infections, but mainly reserved for methicilin resistant Staphylococcus aureus. It is, however, ineffective against intracellular bacteria and hence a particulate form of VCN would be required. Bovine serum albumin (BSA) microspheres of VCN with a mean particle size of 5 +/- 1.6 microm were used. Human microvascular endothelial cells internalized both S. aureus and VCN microspheres in a time and concentration-dependent manner, however, the uptake was inhibited by cytochalasin D. Action of VCN on S. aureus in the intracellular microenvironment decreased the bacterial load considerably.

A method using solid-phase extraction and high-performance liquid chromatography is evaluated for the simultaneous determination of sulfadoxine and pyrimethamine from 0.1 ml of whole blood dried onto filter paper. Extraction recoveries are about 60% for both drugs. The coefficient of variation for intra-assay precision, inter-assay precision and accuracy is less than 10% for sulfadoxine (10-100 microg/ml) and pyrimethamine (1-10 microg/ml).

BackgroundIn vivo efficacy assessments of antimalarials are essential for ensuring effective case management. In Ethiopia, chloroquine (CQ) without primaquine is the first-line treatment for Plasmodium vivax in malarious areas, but artemether-lumefantrine (AL) is also commonly used.Methods and findingsIn 2009, we conducted a 42-day efficacy study of AL or CQ for P. vivax in Oromia Regional State, Ethiopia. Individuals with P. vivax monoinfection were enrolled. Primary endpoint was day 28 cure rate. In patients with recurrent parasitemia, drug level and genotyping using microsatellite markers were assessed. Using survival analysis, uncorrected patient cure rates at day 28 were 75.7% (95% confidence interval (CI) 66.8-82.5) for AL and 90.8% (95% CI 83.6-94.9) for CQ. During the 42 days of follow-up, 41.6% (47/113) of patients in the AL arm and 31.8% (34/107) in the CQ arm presented with recurrent P. vivax infection, with the median number of days to recurrence of 28 compared to 35 days in the AL and CQ arm, respectively. Using microsatellite markers to reclassify recurrent parasitemias with a different genotype as non-treatment failures, day 28 cure rates were genotype adjusted to 91.1% (95% CI 84.1-95.1) for AL and to 97.2% (91.6-99.1) for CQ. Three patients (2.8%) with recurrent parasitemia by day 28 in the CQ arm were noted to have drug levels above 100 ng/ml.ConclusionsIn the short term, both AL and CQ were effective and well-tolerated for P. vivax malaria, but high rates of recurrent parasitemia were noted with both drugs. CQ provided longer post-treatment prophylaxis than AL, resulting in delayed recurrence of parasitemia. Although the current policy of species-specific treatment can be maintained for Ethiopia, the co-administration of primaquine for treatment of P. vivax malaria needs to be urgently considered to prevent relapse infections.Trial registrationClinicalTrials.gov NCT01052584.

Background Plasmodium falciparum malaria remains a major public health problem. A vital component of malaria control rests on the availability of good quality artemisinin-derivative based combination therapy (ACT) at the correct dose. However, there are increasing reports of poor quality anti-malarials in Africa. Methods Seven collections of artemisinin derivative monotherapies, ACT and halofantrine anti-malarials of suspicious quality were collected in 2002/10 in eleven African countries and in Asia en route to Africa. Packaging, chemical composition (high performance liquid chromatography, direct ionization mass spectrometry, X-ray diffractometry, stable isotope analysis) and botanical investigations were performed. Results Counterfeit artesunate containing chloroquine, counterfeit dihydroartemisinin (DHA) containing paracetamol (acetaminophen), counterfeit DHA-piperaquine containing sildenafil, counterfeit artemether-lumefantrine containing pyrimethamine, counterfeit halofantrine containing artemisinin, and substandard/counterfeit or degraded artesunate and artesunate+amodiaquine in eight countries are described. Pollen analysis was consistent with manufacture of counterfeits in eastern Asia. These data do not allow estimation of the frequency of poor quality anti-malarials in Africa. Conclusions Criminals are producing diverse harmful anti-malarial counterfeits with important public health consequences. The presence of artesunate monotherapy, substandard and/or degraded and counterfeit medicines containing sub-therapeutic amounts of unexpected anti-malarials will engender drug resistance. With the threatening spread of artemisinin resistance to Africa, much greater investment is required to ensure the quality of ACTs and removal of artemisinin monotherapies. The International Health Regulations may need to be invoked to counter these serious public health problems.