Evaluation of the quality of amodiaquine and sulphadoxine/pyrimethamine tablets sold by private wholesale pharmacies in Dar Es Salaam Tanzania

Antimalarial stocking decisions among medicine retailers in Ghana: implications for quality management and control of malaria

Global health efforts such as malarial control require efficient pharmaceutical supply chains to ensure effective delivery of quality-assured medicines to those who need them. However, very little is currently known about decision-making processes within antimalarial supply chains and potential vulnerabilities to substandard and falsified medicines. Addressing this gap, we report on a study that investigated decision-making around the stocking of antimalarial products among private-sector medicine retailers in Ghana. Licensed retail pharmacies and over-the-counter (OTC) medicine retail outlets were sampled across six regions of Ghana using a two-stage stratified sampling procedure, with antimalarial medicines categorised as 'expensive,' 'mid-range,' and 'cheaper,' relative to other products in the shop. Retailers were asked about their motivations for choosing to stock particular products over others. The reasons were grouped into three categories: financial, reputation/experience and professional recommendation. Reputation/experience (76%, 95% CI 72.0% to 80.7%) were the drivers of antimalarial stocking decisions, followed by financial reasons (53.2%, 95% CI 48.1% to 58.3%) and recommendation by certified health professionals (24.7%, 95% CI 20.3% to 29.1%). Financial considerations were particularly influential in stocking decisions of cheaper medicines. Moreover, pharmacies and OTCs without a qualified pharmacist were significantly more likely to indicate financial reasons as a motivation for stocking decisions. No significant differences in stocking decisions were found by geographical location (zone and urban/rural) or outlet (pharmacy/OTC). These findings have implications for the management of antimalarial quality across supply chains in Ghana, with potentially important consequences for malaria control, particularly in lower-income areas where people rely on low-cost medication.

Quality of Antimalarial Drugs in East Africa: A Systematic Review

Background

The use of poor quality drugs will have multiple consequences with an extended hazard of growing drug-resistant strains.

Purpose

The review aimed to provide the quality status of antimalarial drugs in East Africa.

Data Source

PubMed, Scopus, Web of Science, and Google Scholar were searched from September 5 to September 12, 2021.

Study Selection

The review included articles available as original research targeted at evaluating the quality of antimalarial drugs. For inclusion, data on at least one of the following quality control parameters were required: packaging and labeling, hardness, friability, weight variation/uniformity of weight, disintegration, dissolution, and assay/percentage purity. Mendeley citation manager version 1.19.4 was used to avoid duplication and organize references, and titles and abstracts were primarily used for screening.

Data Extraction

The sample collection site, drug name, and the quality control parameters tested were retrieved from the selected studies.

Data synthesis

 Totally, 300 antimalarial drug samples from Ethiopia, Kenya and Tanzania were included in this review. No antimalarial drug tested failed the identification and disintegration test. However, 15.93% (36/226), 5.00% (15/300), and 1.90% (3/158) of antimalarial samples failed the dissolution, assay and mass uniformity test, respectively. Moreover, amodiaquine and sulfadoxine/pyrimethamine samples failed dissolution and assay tests. In addition, amodiaquine samples failed the mass uniformity test. However, artemether/lumefantrine and quinine passed all quality control parameters tested. Overall, 19.67% (59/300) of antimalarial drug samples did not meet at least one quality control parameter. And the higher faller rate was reported for sulfadoxine/pyrimethamine accounting for 52.86% (37/70).

Conclusions

An unneglected amount of antimalarial drug failed to meet at least one quality control parameter. Strengthening pharmaceutical management systems, including post-marketing surveillance, and providing the resources required for medication quality assurance, are recommended.

Quality of selected anti-retroviral medicines: Tanzania Mainland market as a case study

Background

Antiretroviral drugs (ARVs) have significantly reduced morbidity, mortality and improved the quality of life of people living with HIV infection. Poor quality ARVs may result in harmful consequences such as adverse drug reactions, treatment failure and development of drug resistant strains and sometimes death, which in turn may undermine the healthcare delivery system. To ensure optimal treatment outcomes, medicines quality control must be undertaken regularly. This study was aimed at evaluating the quality of ARVs circulating on the Tanzania Mainland market.

Methods

This was a survey study. ARVs samples were collected in 20 regions of Tanzania Mainland, between 2012 and 2018. All sampled ARVs were subjected to screening testing using the Global Pharma Health Fund® Mini-Lab kits. Sampled ARV’s that failed screening test or yielded doubtful results and 10 % (10 %) of all that complied with the screening test requirements were selected for full quality control testing. Quality control testing was conducted at the Tanzania Medicines and Medical Devices Authority (TMDA) laboratory a World Health Organisation prequalified. Samples collected from the medicine distribution outlets were also, subjected to product information review.

Results

A total of 2,630 samples were collected, of which 83.7 % (2200/2630) were from port of entry (POEs). All sampled ARVs were screened and conformed to the specifications, except of the fixed dose combination (FDC) lopinavir/ritonavir 0.27 % (7/2630) and lamivudine/zidovudine/nevirapine 0.27 % (7/2630) that failed the disintegration test. Out of the 100 samples selected for full quality control testing, 3 % of them failed to comply with the specifications, of which FDC stavudine/lamivudine/nevirapine failed disintegration and assay tests 2 % (2/100) and 1 % (1/100), respectively. Samples failing the assay test had low content of stavudine (86.6 %) versus specification limits (90 -110 %). Out of the 430 samples which were subjected to product information review, 25.6 % (110/430) failed to comply with the TMDA packaging and labelling requirements.

Conclusions

The quality of majority of ARVs circulating on the Tanzania Mainland market was good, even so, significant deficiencies on labelling and packaging were observed. These results call for continuous monitoring of quality of medicines circulating on the Tanzania Mainland market.

Patient safety and public health concerns: poor dissolution rate of pioglitazone tablets obtained from China, Myanmar and internet sites

Background

Poor quality medicines have serious implications for public health. The aim of this study was to explore the quality of the antidiabetic pioglitazone, using samples collected in China and Myanmar, and samples purchased online.

Methods

In this cross-sectional study, we examined samples (n = 163) collected from hospitals in Shanghai, China in 2012 (n = 44), products purchased via the internet and imported into Japan in 2013 (n = 59), and samples purchased in shops in Yangon, Myanmar in 2015 (n = 60). Collected samples were subjected to visual inspection, authenticity investigation and quality testing (potency, content uniformity and dissolution test) by high-performance liquid chromatography. Samples were rated as compliant or non-compliant based on the relevant pharmacopoeial acceptance criteria.

Results

Visual inspection of all samples revealed compliant products. However, responses from manufacturers during authenticity investigation were poor. Among the n = 44 samples from China, one was non-compliant in the potency test. Among the n = 59 samples personally imported into Japan, 38% of generic samples were found to be non-compliant. In Myanmar, 13.3% of samples were non-compliant. Non-compliant samples predominantly failed in the dissolution test. All non-compliant samples were generic.

Conclusions

Despite the apparent satisfactory outcome on the samples from China, pioglitazone samples collected in Myanmar and purchased online for personal import into Japan included many substandard products, which failed quality assessment predominantly because of poor dissolution. Internet providers did not comply with Japanese regulations in various respects.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40360-021-00478-x.

In-vitro and in-vivo performance of locally manufactured glimepiride tablet generics compared to the innovator (Amaryl®) tablets

Both physicians and patients in Egypt often express concern as to the clinical efficacy of locally manufactured glimepiride tablet generics whenever adequate control of blood sugar is not achieved with these products. The present study addresses this issue. The pharmaceutical quality of four glimepiride 3 mg tablet generics purchased in Egypt from local pharmacies was assessed relative to the innovator product (Amaryl^®), 3 mg tablets. Uniformity of Content, dissolution rate, disintegration time and hardness were determined. Products were subjected to a 6-month stability study under stress condition (40 °c/75%RH). The same brands were evaluated in vivo in a clinical study conducted in the Main Alexandria University Hospital involving 100 patients (20 patients per brand including innovator). Patients recruited were newly diagnosed type II diabetics. Glimepiride tablets were used as a monotherapy. Fasting blood glucose (FBG) and glycosylated hemoglobin (HbA1C) were measured over a period of 3 months. The results indicated differences (p ≤ .05) in the in vitro and in vivo performance of the tested products; innovator and tested generics substitution was not evident. The stability study indicated that the tablets were prone to deterioration in their physical characteristics, particularly dissolution profiles, upon storage of blisters in a hot humid climate. In vitro/in vivo correlations were investigated seeking to identify an in vitro test to serve as a performance indicator for glimepiride tablets in the post-marketing period. The similarity factor (f₂) of the dissolution data proved to be a good indicator of in vivo performance of the tablets.

Comparison of malaria treatment outcome of generic and innovator's anti-malarial drugs containing artemether-lumefantrine combination in the management of uncomplicated malaria amongst Tanzanian children

Background

In 2006, artemether–lumefantrine (ALU), specifically Coartem^® (Novartis Pharma AG, Basel Switzerland), was approved as the first-line drug for treatment of uncomplicated malaria in Tanzania. Due to poor availability and affordability of the innovator’s product, the government of Tanzania in 2013 prequalified the use of generic anti-malarial drugs, whereby Artefan^® (Ajanta, Pharma Ltd, India) was the first to be approved.

Methods

This was an equivalence prospective study that aimed to determine the effectiveness of anti-malarial generic Artefan^® in comparison with innovator’s product Coartem^®. Patients aged 6 to 59 months with uncomplicated malaria were recruited and randomized to either receive Artefan^® or Coartem^® as a control. Participants were required to revisit clinic five times as follow up to monitor treatment outcome as per World Health Organization recommendations. On each visit, thick and thin blood smears, dried blood spot (DBS), haemoglobin concentrations and auxiliary temperature were performed and documented.

Results

Out of 230 recruited participants, 200 met inclusion criteria and were randomized equally to receive Artefan^® and Coartem^®. The overall PCR uncorrected cure rate were 80% for Artefan^® and 75% for Coartem^® (p = 0.44). Adequate clinical and parasitological response were 82.1% for Artefan^® and 74.7% for Coartem^®, and there was no early treatment failure (ETF) observed in both arms of treatment. Both drugs showed excellent early parasite clearance, whereby no participants had peripheral parasitaemia on day 3. Late clinical failures (LCF) were 3.6% for Artefan^® and 1.3% for Coartem^® (p = 0.31), and late parasitological failure (LPF) were 15.4% for Artefan^® and 22.7% for Coartem^® (p = 0.32). Mean haemoglobin (g/dl) concentrations observed on day 28 were higher compared to day 0 for both drugs, although not statistically significant. Only one (1.3%) participant on Artefan^® had temperature ≥ 37.5 °C on day 3.

Conclusion

The findings of this study indicate that both Artefan^® and Coartem^® are equivalent and effective in the management of uncomplicated malaria amongst children in the Coast part of Tanzania.

Anti-malarial medicine quality field studies and surveys: a systematic review of screening technologies used and reporting of findings

BACKGROUND

Assessing the quality of medicines in low-middle income countries (LMICs) relies primarily on human inspection and screening technologies, where available. Field studies and surveys have frequently utilized screening tests to analyse medicines sampled at the point of care, such as health care facilities and medicine outlets, to provide a snap shot of medicine quality in a specific geographical area. This review presents an overview of the screening tests typically employed in surveys to assess anti-malarial medicine quality, summarizes the analytical methods used, how findings have been reported and proposes a reporting template for future studies.

METHODS

A systematic search of the peer-reviewed and grey literature available in the public domain (including national and multi-national medicine quality surveys) covering the period 1990-2016 was undertaken. Studies were included if they had used screening techniques to assess the quality of anti-malarial medicines. As no standardized set of guidelines for the methodology and reporting of medicine quality surveys exist, the included studies were assessed for their standard against a newly proposed list of criteria.

RESULTS

The titles and abstracts of 4621 records were screened and only 39 were found to meet the eligibility criteria. These 39 studies utilized visual inspection, disintegration, colorimetry and Thin Layer Chromatography (TLC) either as components of the Global Pharma Health Fund (GPHF) MiniLab^® or as individual tests. Overall, 30/39 studies reported employing confirmatory testing described in international pharmacopeia to verify the quality of anti-malarials post assessment by a screening test. The authors assigned scores for the 23 criteria for the standard of reporting of each study.

CONCLUSIONS

There is considerable heterogeneity in study design and inconsistency in reporting of field surveys of medicine quality. A lack of standardization in the design and reporting of studies of medicine quality increases the risk of bias and error, impacting on the generalizability and reliability of study results. The criteria proposed for reporting on the standard of studies in this review can be used in conjunction with existing medicine quality survey guidelines as a checklist for designing and reporting findings of studies. The review protocol has been registered with PROSPERO (CRD42015026782).

Modelling the impact of antimalarial quality on the transmission of sulfadoxine-pyrimethamine resistance in Plasmodium falciparum

Background

The use of poor quality antimalarial medicines, including the use of non-recommended medicines for treatment such as sulfadoxine-pyrimethamine (SP) monotherapy, undermines malaria control and elimination efforts. Furthermore, the use of subtherapeutic doses of the active ingredient(s) can theoretically promote the emergence and transmission of drug resistant parasites.

Methods

We developed a deterministic compartmental model to quantify the impact of antimalarial medicine quality on the transmission of SP resistance, and validated it using sensitivity analysis and a comparison with data from Kenya collected in 2006. We modelled human and mosquito population dynamics, incorporating two Plasmodium falciparum subtypes (SP-sensitive and SP-resistant) and both poor quality and good quality (artemether-lumefantrine) antimalarial use.

Findings

The model predicted that an increase in human malaria cases, and among these, an increase in the proportion of SP-resistant infections, resulted from an increase in poor quality SP antimalarial use, whether it was full- or half-dose SP monotherapy.

Interpretation

Our findings suggest that an increase in poor quality antimalarial use predicts an increase in the transmission of resistance. This highlights the need for stricter control and regulation on the availability and use of poor quality antimalarial medicines, in order to offer safe and effective treatments, and work towards the eradication of malaria.

Amorphous Sulfadoxine: A Physical Stability and Crystallization Kinetics Study

Poor aqueous solubility of drugs and the improvement thereof has always been a challenge for the pharmaceutical industry. With this, one of the focuses of the pharmaceutical research scientist involves investigating possible metastable forms of a given drug to be incorporated into solid dosage forms. The rationale being, the improved solubility offered by the metastable solid-state forms of drugs. Solubility remains a major challenge for formulation scientists, especially with antimicrobial agents where the emergence of resistance is directly dependent on the concentration and duration of the parasite exposed to the drug. Sulfadoxine-pyrimethamine combination therapies are still the recommended treatments for uncomplicated Plasmodium falciparum malaria. The aim of this study was to prepare an amorphous form of sulfadoxine and to investigate the stability and recrystallization behavior thereof. The amorphous form was prepared by the well-known quench cooling of the melt. The physico-chemical properties and stability of amorphous sulfadoxine were studied using hot-stage microscopy (HSM), scanning electron microscopy (SEM), x-ray powder diffractometry (XRPD), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), as well as microcalorimetry. The recrystallization kinetics were studied isothermally by applying the Johnson-Mehl-Avrami model and non-isothermally by applying the Kissinger model. The physical stabilization of the amorphous form was investigated using physical mixtures of amorphous sulfadoxine with polyvinylpyrrolidone-25 (PVP-25). It was proved that sulfadoxine is a good glass former with relative high physical stability; however, water acts as a strong plasticizer for amorphous sulfadoxine, detrimentally affecting the stability during exposure to high moisture conditions.

Quality of Artemisinin-Containing Antimalarials in Tanzania's Private Sector--Results from a Nationally Representative Outlet Survey

Ensuring that artemisinin-containing antimalarials (ACAs) are of good quality is a key component of effective malaria treatment. There are concerns that a high proportion of ACAs are falsified or substandard, though estimates are rarely based on representative data. During a nationally representative survey in Tanzania, ACAs were purchased from private retail drug outlets, and the active pharmaceutical ingredient (API) was measured. All 1,737 ACAs contained the labeled artemisinin derivative, with 4.1% being outside the 85-115% artemisinin API range defined as acceptable quality. World Health Organization (WHO) prequalified drugs had 0.1 times the odds of being poor quality compared with non-prequalified ACAs for the artemisinin component. When partner components of combination therapies were also considered, 12.1% were outside the acceptable API range, and WHO prequalified ACAs had 0.04 times the odds of being poor quality. Although the prevalence of poor quality ACAs was lower than reported elsewhere, the minority of samples found to be substandard is a cause for concern. Improvements in quality could be achieved by increasing the predominance of WHO prequalified products in the market. Continued monitoring of quality standards is essential.

Substandard/counterfeit antimicrobial drugs

Substandard/counterfeit antimicrobial drugs are a growing global problem. The most common substandard/counterfeit antimicrobials include beta-lactams (among antibiotics) and chloroquine and artemisin derivatives (among antimalarials). The most common type of substandard/counterfeit antimicrobial drugs have a reduced amount of the active drug, and the majority of them are manufactured in Southeast Asia and Africa. Counterfeit antimicrobial drugs may cause increased mortality and morbidity and pose a danger to patients. Here we review the literature with regard to the issue of substandard/counterfeit antimicrobials and describe the prevalence of this problem, the different types of substandard/counterfeit antimicrobial drugs, and the consequences for the individuals and global public health. Local, national, and international initiatives are required to combat this very important public health issue.

Substandard drugs: a potential crisis for public health

Poor-quality medicines present a serious public health problem, particularly in emerging economies and developing countries, and may have a significant impact on the national clinical and economic burden. Attention has largely focused on the increasing availability of deliberately falsified drugs, but substandard medicines are also reaching patients because of poor manufacturing and quality-control practices in the production of genuine drugs (either branded or generic). Substandard medicines are widespread and represent a threat to health because they can inadvertently lead to healthcare failures, such as antibiotic resistance and the spread of disease within a community, as well as death or additional illness in individuals. This article reviews the different aspects of substandard drug formulation that can occur (for example, pharmacological variability between drug batches or between generic and originator drugs, incorrect drug quantity and presence of impurities). The possible means of addressing substandard manufacturing practices are also discussed. A concerted effort is required on the part of governments, drug manufacturers, charities and healthcare providers to ensure that only drugs of acceptable quality reach the patient.

A pilot study on quality of artesunate and amodiaquine tablets used in the fishing community of Tema, Ghana

BACKGROUND

The ineffectiveness of artesunate and amodiaquine tablets in malaria treatment remains a health burden to WHO and governments of malaria-endemic countries, including Ghana. The proliferation of illegitimate anti-malarial drugs and its use by patients is of primary concern to international and local drug regulatory agencies because such drugs are known to contribute to the development of the malaria-resistant parasites in humans. No data exist on quality of these drugs in the fishing village communities in Ghana although the villagers are likely users of such drugs. A pilot study on the quality of anti-malarial tablets in circulation during the major fishing season at a malarious fishing village located along the coast of Tema in southern Ghana was determined.

METHODS

Blisterpacks of anti-malarial tablets were randomly sampled. The International Pharmacopoeia and Global Pharma Health Fund Minilab protocols were used to assess the quality of anti-malarial tablets per blisterpacks allegedly manufactured by Guilin Pharmaceutical Co Ltd, China (GPCL) and Letap Pharmaceuticals Ltd, Ghana (LPL) and sold in chemical sales outlets at Kpone-on-Sea. Ferric chloride and cobaltous thiocyanate tests confirmed the presence of active ingredients in the tablets. A confirmatory test for the active ingredient was achieved with artesunate (ICRS1409) and amodiaquine (ICRS0209) reference standards. A high performance liquid chromatography analysis confirmed the amount of artesunate found in tablets.

RESULTS

Based on the International Pharmacopoeia acceptable range of 96/98 to 102% for genuine artesunate per tablet, 10% [relative standard deviation (RSD): 3.2%] of field-selected artesunate blisterpack per tablets manufactured by GPCL, and 50% (RSD: 5.1%) of a similar package per tablet by LPL, passed the titrimetric test. However, 100% (RSD: 2.2%) of amodiaquine blisterpack per tablet by GPCL were found to be within the International Pharmacopeia acceptable range of 90 to 110% for genuine amodiaquine in tablet, whilst 17% of a similar package per tablet by LPL failed spectrophotometric testing.

CONCLUSION

Inadequate amounts of artesunate and amodiaquine detected in the tablets suggest that both pharmaceutical companies may not be following recommended drug formulation procedures, or the active pharmaceutical ingredients might have been degraded by improper storage conditions. Thus, drugs being sold at Kpone-on-Sea, Ghana may likely be classified as substandard drugs and not suitable for malaria treatment.

Review of the quality of pediatric medications in developing countries

The quality of essential medicines for pediatric populations in developing countries is largely unknown. This review examines quality studies (2000-2011) of medicines on the WHO Essential Medicine List for Children, the quality of a subset of pediatric formulations, and the association of these poor quality medicines with adverse clinical outcomes. We searched Embase, Medline, BIOSIS, and IPA using MeSH subject terms for quality measures, medicine formulations, and substandard medicines and combined these with 267 medicines, and 91 low-income and lower-middle-income countries. Seventy articles met our inclusion criteria examining the quality of 75 medicines from 28 countries. Content and dissolution tests were utilized most often. Results indicate that antibacterials, antifungals, and antiretrovirals were consistently of good quality. Quality tests on pediatric formulations were performed on 55 of 75 of the medicines studied and followed the general trend of quality results. Three studies were included that examined clinical consequences of substandard medicines-two cases of diethylene glycol poisoning and one case of substandard malaria drugs. We conclude that there is a need for more quality studies of pediatric formulations of essential medicines in developing countries and their clinical consequences.

Poor-quality antimalarial drugs in southeast Asia and sub-Saharan Africa

Poor-quality antimalarial drugs lead to drug resistance and inadequate treatment, which pose an urgent threat to vulnerable populations and jeopardise progress and investments in combating malaria. Emergence of artemisinin resistance or tolerance in Plasmodium falciparum on the Thailand-Cambodia border makes protection of the effectiveness of the drug supply imperative. We reviewed published and unpublished studies reporting chemical analyses and assessments of packaging of antimalarial drugs. Of 1437 samples of drugs in five classes from seven countries in southeast Asia, 497 (35%) failed chemical analysis, 423 (46%) of 919 failed packaging analysis, and 450 (36%) of 1260 were classified as falsified. In 21 surveys of drugs from six classes from 21 countries in sub-Saharan Africa, 796 (35%) of 2297 failed chemical analysis, 28 (36%) of 77 failed packaging analysis, and 79 (20%) of 389 were classified as falsified. Data were insufficient to identify the frequency of substandard (products resulting from poor manufacturing) antimalarial drugs, and packaging analysis data were scarce. Concurrent interventions and a multifaceted approach are needed to define and eliminate criminal production, distribution, and poor manufacturing of antimalarial drugs. Empowering of national medicine regulatory authorities to protect the global drug supply is more important than ever.

Quality of anti-malarials collected in the private and informal sectors in Guyana and Suriname

Background

Despite a significant reduction in the number of malaria cases in Guyana and Suriname, this disease remains a major problem in the interior of both countries, especially in areas with gold mining and logging operations, where malaria is endemic. National malaria control programmes in these countries provide treatment to patients with medicines that are procured and distributed through regulated processes in the public sector. However, availability to medicines in licensed facilities (private sector) and unlicensed facilities (informal sector) is common, posing the risk of access to and use of non-recommended treatments and/or poor quality products.

Methods

To assess the quality of circulating anti-malarial medicines, samples were purchased in the private and informal sectors of Guyana and Suriname in 2009. The sampling sites were selected based on epidemiological data and/or distance from health facilities. Samples were analysed for identity, content, dissolution or disintegration, impurities, and uniformity of dosage units or weight variation according to manufacturer, pharmacopeial, or other validated method.

Results

Quality issues were observed in 45 of 77 (58%) anti-malarial medicines sampled in Guyana of which 30 failed visual & physical inspection and 18 failed quality control tests. The proportion of monotherapy and ACT medicines failing quality control tests was 43% (13/30) and 11% (5/47) respectively. A higher proportion of medicines sampled from the private sector 34% (11/32) failed quality control tests versus 16% (7/45) in the informal sector. In Suriname, 58 medicines were sampled, of which 50 (86%) were Artecom®, the fixed-dose combination of piperaquine-dihydroartemisinin-trimethoprim co-blistered with a primaquine phosphate tablet. All Artecom samples were found to lack a label claim for primaquine, thus failing visual and physical inspection.

Conclusions

The findings of the studies in both countries point to significant problems with the quality of anti-malarial medicines available in private and informal sector facilities as well as the availability of therapy not compliant with national treatment guidelines. They also stress the need to strengthen regulatory control efforts on the availability of anti-malarial medicines in these sectors and in endemic areas.

Implementation of basic quality control tests for malaria medicines in Amazon Basin countries: results for the 2005-2010 period

Background

Ensuring the quality of malaria medicines is crucial in working toward malaria control and eventual elimination. Unlike other validated tests that can assess all critical quality attributes, which is the standard for determining the quality of medicines, basic tests are significantly less expensive, faster, and require less skilled labour; yet, these tests provide reproducible data and information on several critical quality attributes, such as identity, purity, content, and disintegration. Visual and physical inspection also provides valuable information about the manufacturing and the labelling of medicines, and in many cases this inspection is sufficient to detect counterfeit medicines. The Promoting the Quality of Medicines (PQM) programme has provided technical assistance to Amazon Malaria Initiative (AMI) countries to implement the use of basic tests as a key screening mechanism to assess the quality of malaria medicines available to patients in decentralized regions.

Methods

Trained personnel from the National Malaria Control Programmes (NMCPs), often in collaboration with country’s Official Medicine Control Laboratory (OMCL), developed country- specific protocols that encompassed sampling methods, sample analysis, and data reporting. Sampling sites were selected based on malaria burden, accessibility, and geographical location. Convenience sampling was performed and countries were recommended to store the sampled medicines under conditions that did not compromise their quality. Basic analytical tests, such as disintegration and thin layer chromatography (TLC), were performed utilizing a portable mini-laboratory.

Results

Results were originally presented at regional meetings in a non-standardized format that lacked relevant medicines information. However, since 2008 information has been submitted utilizing a template specifically developed by PQM for that purpose. From 2005 to 2010, the quality of 1,663 malaria medicines from seven AMI countries was evaluated, mostly collected from the public sector, 1,445/1,663 (86.9%). Results indicate that 193/1,663 (11.6%) were found not to meet quality specifications. Most failures were reported during visual and physical inspection, 142/1663 (8.5%), and most of these were due to expired medicines, 118/142 (83.1%). Samples failing TLC accounted for 27/1,663 (1.6%) and those failing disintegration accounted for 24/1,663 (1.4%). Medicines quality failures decreased significantly during the last two years.

Conclusions

Basic tests revealed that the quality of medicines in the public sector improved over the years, since the implementation of this type of quality monitoring programme in 2005. However, the lack of consistent confirmatory tests in the quality control (QC) laboratory, utilizing methods that can also evaluate additional quality attributes, could still mask quality issues. In the future, AMI countries should improve coordination with their health authorities and their QC lab consistently, to provide a more complete picture of malaria medicines quality and support the implementation of corrective actions. Facilities in the private and informal sectors also should be included when these sectors constitute an important source of medicines used by malaria patients.

Quality of essential drugs in tropical countries: evaluation of antimalarial drugs in the Brazilian Health System

INTRODUCTION: The emergence of drug resistance is one of the main problems concerning malaria treatment. The use of counterfeit and/or substandard antimalarial drugs can contribute to the development of parasite resistance. Thus, the aim of this study was to evaluate the quality of antimalarial drugs distributed in Brazil. METHODS: Samples containing chloroquine phosphate, mefloquine hydrochloride, primaquine phosphate, and quinine sulfate tablets were delivered to the Rio de Janeiro central storeroom (CENADI), state storerooms (SS), and Basic Health Units (BHUs) in the north region of Brazil - a total of 10 sample sets. After 5 months of storage, the samples were collected, and in vitro quality control analyses according to official and published methods were performed. RESULTS: Inadequate drug storage conditions were found in two SS and in all BHUs evaluated. There were no quality deviations found in the chloroquine samples. The quinine samples exhibited weight variation above the allowed limits. The primaquine samples were found to have packaging deficiency. The release of mefloquine in samples from some regions showed a statistically significant difference when compared with the CENADI samples. CONCLUSIONS: It is important to periodically evaluate the quality and storage conditions of essential drugs. The quality deviations found with the primaquine and quinine samples are not related to storage conditions and must be addressed urgently. The decreased mefloquine release from tablets is related to formulation problems or influenced by inadequate storage conditions, prompting further investigation. Even with the mentioned problems, the samples would probably not contribute to resistant parasite selection.

Availability of antimalarial drugs and evaluation of the attitude and practices for the treatment of uncomplicated malaria in bangui, central african republic

National malaria management policy is based upon the availability of effective and affordable antimalarial drugs. This study was undertaken to evaluate the quality of the treatment of uncomplicated malaria cases in Bangui, an area with multidrug-resistant parasites, at a time preceding implementation of a new therapeutic policy relying on the artemisinin derivative combined treatment artemether-lumefantrine. A cross-sectional study was carried out in Bangui city to assess availability of antimalarial drugs and the performances of health workers in the management of uncomplicated malaria. Availability of drugs was recorded in all drugs wholesalers (n = 3), all pharmacies in health facilities (n = 14), private drugstores (n = 15), and in 60 non-official drug shops randomly chosen in the city. Despite a limited efficacy at the time of the survey, chloroquine remained widely available in the official and nonofficial markets. Artemisinin derivatives used in monotherapy or in combination were commonly sold. In health care facilities, 93% of the uncomplicated malaria cases were treated in the absence of any laboratory confirmation and the officially recommended treatment, amodiaquine-sulfadoxine/pyrimethamine, was seldom prescribed. Thus, the national guidelines for the treatment of uncomplicated malaria are not followed by health professionals in Bangui. Its use should be implemented while a control of importation of drug has to be reinforced.

Quality of anti-malarial drugs provided by public and private healthcare providers in south-east Nigeria

Background

There is little existing knowledge about actual quality of drugs provided by different providers in Nigeria and in many sub-Saharan African countries. Such information is important for improving malaria treatment that will help in the development and implementation of actions designed to improve the quality of treatment. The objective of the study was to determine the quality of drugs used for the treatment of malaria in a broad spectrum of public and private healthcare providers.

Methods

The study was undertaken in six towns (three urban and three rural) in Anambra state, south-east Nigeria. Anti-malarials (225 samples), which included artesunate, dihydroartemisinin, sulphadoxine-pyrimethamine (SP), quinine, and chloroquine, were either purchased or collected from randomly selected providers. The quality of these drugs was assessed by laboratory analysis of the dissolution profile using published pharmacopoeial monograms and measuring the amount of active ingredient using high performance liquid chromatography (HPLC).

Findings

It was found that 60 (37%) of the anti-malarials tested did not meet the United States Pharmacopoeia (USP) specifications for the amount of active ingredients, with the suspect drugs either lacking the active ingredients or containing suboptimal quantities of the active ingredients. Quinine (46%) and SP formulations (39%) were among drugs that did not satisfy the tolerance limits published in USP monograms. A total of 78% of the suspect drugs were from private facilities, mostly low-level providers, such as patent medicine dealers (vendors).

Conclusion

This study found that there was a high prevalence of poor quality drugs. The findings provide areas for public intervention to improve the quality of malaria treatment services. There should be enforced checks and regulation of drug supply management as well as stiffer penalties for people stocking substandard and counterfeit drugs.

A nationwide survey of the quality of antimalarials in retail outlets in Tanzania

INTRODUCTION

Retail pharmaceutical products are commonly used to treat fever and malaria in sub-Saharan African countries. Small scale studies have suggested that poor quality antimalarials are widespread throughout the region, but nationwide data are not available that could lead to generalizable conclusions about the extent to which poor quality drugs are available in African communities. This study aimed to assess the quality of antimalarials available from retail outlets across mainland Tanzania.

METHODS AND FINDINGS

We systematically purchased samples of oral antimalarial tablets from retail outlets across 21 districts in mainland Tanzania in 2005. A total of 1080 antimalarial formulations were collected including 679 antifol antimalarial samples (394 sulfadoxine/pyrimethamine and 285 sulfamethoxypyrazine/pyrimethamine), 260 amodiaquine samples, 63 quinine samples, and 51 artemisinin derivative samples. A systematic subsample of 304 products was assessed for quality by laboratory based analysis to determine the amount of the active ingredient and dissolution profile by following the published United States Pharmacopoeia (USP) monogram for the particular tablet being tested. Products for which a published analytical monogram did not exist were assessed on amount of active ingredient alone. Overall 38 or 12.2% of the samples were found to be of poor quality. Of the antifolate antimalarial drugs tested 13.4% were found to be of poor quality by dissolution and content analysis using high-performance liquid chromatography (HPLC). Nearly one quarter (23.8%) of quinine tablets did not comply within the tolerance limits of the dissolution and quantification analysis. Quality of amodiaquine drugs was relatively better but still unacceptable as 7.5% did not comply within the tolerance limits of the dissolution analysis. Formulations of the artemisinin derivatives all contained the stated amount of active ingredient when analysed using HPLC alone.

CONCLUSIONS

Substandard antimalarial formulations were widely available in Tanzania at the time of this study. No products were detected that did not contain any amount of the stated active ingredient. Quinine and sulfadoxine/pyrimethamine products were the most widely available and also the most likely to be of poor quality. Substandard products were identified in all parts of the country and were labeled as made by both domestic and international manufacturers. With the expansion of the retail pharmaceutical sector as a delivery channel for antimalarial formulations the need for regular nationwide monitoring of their quality will become increasingly important.

Substandard medicines in resource-poor settings: a problem that can no longer be ignored

The circulation of substandard medicines in the developing world is a serious clinical and public health concern. Problems include under or over concentration of ingredients, contamination, poor quality ingredients, poor stability and inadequate packaging. There are multiple causes. Drugs manufactured for export are not regulated to the same standard as those for domestic use, while regulatory agencies in the less-developed world are poorly equipped to assess and address the problem. A number of recent initiatives have been established to address the problem, most notably the WHO pre-qualification programme. However, much more action is required. Donors should encourage their partners to include more explicit quality requirements in their tender mechanisms, while purchasers should insist that producers and distributors supply drugs that comply with international quality standards. Governments in rich countries should not tolerate the export of substandard pharmaceutical products to poor countries, while developing country governments should improve their ability to detect substandard medicines.

Substandard anti-malarial drugs in Burkina Faso

BACKGROUND

There is concern about an increasing infiltration of markets by substandard and fake medications against life-threatening diseases in developing countries. This is particularly worrying with regard to the increasing resistance development of Plasmodium falciparum against affordable anti-malarial medications, which has led to a change to more expensive drugs in most endemic countries.

METHODS

A representative sample of modern anti-malarial medications from licensed (public and private pharmacies, community health workers) and illicit (market and street vendors, shops) sources has been collected in the Nouna Health District in north-western Burkina Faso in 2006. All drugs were tested for their quality with the standard procedures of the German Pharma Health Fund-Minilab. Detected low standard drugs were re-tested with European Pharmacopoeia 2.9.1 standards for disintegration and ultraviolet-visible spectroscopy at the laboratory of the Heidelberg University for confirmation.

RESULTS

Overall, 86 anti-malarial drug samples were collected, of which 77 samples have been included in the final analysis. The sample consisted of 39/77 (50%) chloroquine, 10/77 (13%) pyrimethamine-sulphadoxine, 9/77 (12%) quinine, 6/77 (8%) amodiaquine, 9/77 (12%) artesunate, and 4/77 (5%) artemether-lumefantrine. 32/77 (42%) drug samples were found to be of poor quality, of which 28 samples failed the visual inspection, nine samples had substandard concentrations of the active ingredient, four samples showed poor disintegration, and one sample contained non of the stated active ingredient. The licensed and the illicit market contributed 5/47 (10.6%) and 27/30 (90.0%) samples of substandard drugs respectively.

CONCLUSION

These findings provide further evidence for the wide-spread existence of substandard anti-malarial medications in Africa and call for strengthening of the regulatory and quality control capacity of affected countries, particularly in view of the now wider available and substantially more costly artemisinin-based combination therapies.

Antimalarial drug quality in the most severely malarious parts of Africa - a six country study

A range of antimalarial drugs were procured from private pharmacies in urban and peri-urban areas in the major cities of six African countries, situated in the part of that continent and the world that is most highly endemic for malaria. Semi-quantitative thin-layer chromatography (TLC) and dissolution testing were used to measure active pharmaceutical ingredient content against internationally acceptable standards. 35% of all samples tested failed either or both tests, and were substandard. Further, 33% of treatments collected were artemisinin monotherapies, most of which (78%) were manufactured in disobservance of an appeal by the World Health Organisation (WHO) to withdraw these clinically inappropriate medicines from the market. The high persistence of substandard drugs and clinically inappropriate artemisinin monotherapies in the private sector risks patient safety and, through drug resistance, places the future of malaria treatment at risk globally.

Antimalarial drug quality in Africa

BACKGROUND AND OBJECTIVE

There are several reports of sub-standard and counterfeit antimalarial drugs circulating in the markets of developing countries; we aimed to review the literature for the African continent.

METHODS

A search was conducted in PubMed in English using the medical subject headings (MeSH) terms: 'Antimalarials/analysis'[MeSH] OR 'Antimalarials/standards'[MeSH] AND 'Africa'[MeSH]' to include articles published up to and including 26 February 2007. Data were augmented with reports on the quality of antimalarial drugs in Africa obtained from colleagues in the World Health Organization. We summarized the data under the following themes: content and dissolution; relative bioavailability of antimalarial products; antimalarial stability and shelf life; general tests on pharmaceutical dosage forms; and the presence of degradation or unidentifiable impurities in formulations.

RESULTS AND DISCUSSION

The search yielded 21 relevant peer-reviewed articles and three reports on the quality of antimalarial drugs in Africa. The literature was varied in the quality and breadth of data presented, with most bioavailability studies poorly designed and executed. The review highlights the common finding in drug quality studies that (i) most antimalarial products pass the basic tests for pharmaceutical dosage forms, such as the uniformity of weight for tablets, (ii) most antimalarial drugs pass the content test and (iii) in vitro product dissolution is the main problem area where most drugs fail to meet required pharmacopoeial specifications, especially with regard to sulfadoxine-pyrimethamine products. In addition, there are worryingly high quality failure rates for artemisinin monotherapies such as dihydroartemisinin (DHA); for instance all five DHA sampled products in one study in Nairobi, Kenya, were reported to have failed the requisite tests.

CONCLUSIONS

There is an urgent need to strengthen pharmaceutical management systems such as post-marketing surveillance and the broader health systems in Africa to ensure populations in the continent have access to antimalarial drugs that are safe, of the highest quality standards and that retain their integrity throughout the distribution chain through adequate enforcement of existing legislation and enactment of new ones if necessary, and provision of the necessary resources for drug quality assurance.

Drug shop regulation and malaria treatment in Tanzania--why do shops break the rules, and does it matter?

Regulatory infringements are extremely common in low-income countries, especially with respect to retail pharmaceutical sales. There have been few practical suggestions on public policy responses other than stricter regulatory enforcement, which governments are often unable, or unwilling, to do. This paper explores the challenges of regulating retail drug sellers, and potential solutions, through a case study of malaria treatment in rural Tanzania where small drug shops are a common source of medicine. Infringement of health-related regulation was extremely common. Most stores lacked valid permits, and illegal stocking of prescription-only medicines and unpackaged tablets was the norm. Most stocked unregistered drugs, and no serving staff met the qualification requirements. Infringements are likely to have reflected infrequent regulatory inspections, a failure of regulatory authorities to implement sanctions, successful concealment of regulatory violations, and the tacit permission of local regulatory staff. Eliminating regulatory infringements is unlikely to be feasible, and could be undesirable if access to essential medicines is reduced. Alternatives include bringing official drug regulation closer into line with locally legitimate practices; greater use of positive incentives for providers; and consumer involvement. Such a change in approach has the potential to provide a firmer platform for public-private collaboration to improve shop-based treatment.

Counterfeit or substandard antimicrobial drugs: a review of the scientific evidence

There is growing universal concern regarding counterfeit medications. In particular, counterfeit antimicrobial drugs are a threat to public health with many devastating consequences for patients; increased mortality and morbidity and emergence of drug resistance. In addition, physicians treating these patients lose their confidence in the medications used and report high levels of bacterial resistance. The problem with fake and suboptimal medications got worse with the advent of the World Wide Web; a significant proportion of medications that are sold through Internet pharmacies is counterfeit. Various initiatives of the WHO (the International Medical Products Anti-Counterfeiting Taskforce) are hopefully going to tackle this very important public health issue. In this article, we review the available evidence in peer-reviewed articles and World Wide Web information resources regarding the issue of counterfeit antimicrobials.

Rapid Urban Malaria Appraisal (RUMA) III: epidemiology of urban malaria in the municipality of Yopougon (Abidjan)

Background

The thinking behind malaria research and control strategies stems largely from experience gained in rural areas and needs to be adapted to the urban environment.

Methods

A rapid assessment of urban malaria was conducted in Dar es Salaam in June-August, 2003 using a standard Rapid Urban Malaria Appraisal (RUMA) methodology. This study was part of a multi-site study in sub-Saharan Africa supported by the Roll Back Malaria Partnership.

Results

Overall, around one million cases of malaria are reported every year by health facilities. However, school surveys in Dar es Salaam during a dry spell in 2003 showed that the prevalence of malaria parasites was low: 0.8%, 1.4%, 2.7% and 3.7% in the centre, intermediate, periphery and surrounding rural areas, respectively. Health facilities surveys showed that only 37/717 (5.2%) of presenting fever cases and 22/781 (2.8%) of non-fever cases were positive by blood slide. As a result, malaria-attributable fractions for fever episodes were low in all age groups and there was an important over-reporting of malaria cases. Increased malarial infection rates were seen in persons who travelled to rural areas within the past three months. A remarkably high coverage of insecticide-treated nets and a corresponding reduction in malarial infection risk were found.

Conclusion

The number of clinical malaria cases was much lower than routine reporting suggested. Improved malaria diagnosis and re-defined clinical guidelines are urgently required to avoid over-treatment with antimalarials.

The chemical and pharmaceutical equivalence of sulphadoxine/pyrimethamine tablets sold on the Tanzanian market

This study investigated chemical and pharmaceutical equivalence of 11 brands of pyrimethamine-sulphadoxine combination tablets sold on the Tanzanian market. Physical and chemical tests were performed for all the 11 brands. These tests included hardness test, friability, disintegration, dissolution, weight uniformity and assay for the active components. All the brands passed all the quality specifications of the United States Pharmacopoeia (USP) and British Pharmacopoeia (BP) in terms of hardness, friability, disintegration, assay and dissolution test, except for three brands that failed the hardness, disintegration or friability tests. One brand failed both the hardness and disintegration test; one failed the hardness test, whereas another one failed the friability test. The percentage content of pyrimethamine in the brands was in the range of 91.04-100.20% whereas that of sulphadoxine ranged from 91.53% to 99.88%. There were no major differences between the different brands of tablets containing pyrimethamine and sulphadoxine and the innovator product (Fansidar), and all brands were physically and chemically equivalent. The results indicate that the post-market surveillance and registration process in Tanzania is having an impact on product quality as there was no brand which could be considered of very poor quality. Impurity profiling of all the locally produced brands indicated that they all contained the same sulphadoxine impurity, which was absent in the innovator product, suggesting a common source of generic raw material.

Adoption of the new antimalarial drug policy in Tanzania - a cross-sectional study in the community

OBJECTIVE

To assess the diffusion of the change of first line antimalarial drug from chloroquine (CQ) to sulphadoxine/pyrimethamine (SP) at household level in a rural district of Tanzania less than a year after the policy implementation.

METHODS

Caretakers in 729 households were interviewed on knowledge of the new policy, home stocking of antimalarials, home-treatment practices of children younger than 5 years with fever, health-seeking behaviour and experience of SP. SP and CQ levels in blood were analysed from 328 children younger than 5 years in the households. Twelve focus group discussions (FGD) were performed with mothers, fathers and health workers.

RESULTS

About 51% of the population knew that SP was the first line antimalarial. Only 8% of mothers stocked antimalarials, and only 4% stated self-treatment as the first action. We estimated that 84% of the children who had had fever during the last 4 weeks sought care at public health facilities. SP was detectable in 18% of the total child population and in 32% of those with reported fever, CQ in only 5% and 7%, respectively. The FGDs revealed negative perceptions of SP and fear of severe adverse reactions with mass media reported as key informant.

CONCLUSION

The policy had diffused to the communities in the sense that CQ had been changed to SP, which was well known as first line treatment. Moreover, there was a reported dramatic change from self-treatment with CQ to seeking care at public health facilities where SP was given under observation.

Can amodiaquine be used safely during pregnancy?

Several African countries have begun using amodiaquine-containing combinations as first-line antimalarial treatment, with the result that a substantial number of pregnant women are likely to be exposed to amodiaquine. However, little information is available on amodiaquine safety and efficacy during pregnancy. Between 1948 and 1990 only six published studies reported amodiaquine use in pregnancy. Only one publication mentioned adverse events, without details. Six additional studies on amodiaquine delivered by mass drug administration or medicated salts gave very little information on amodiaquine safety. Therefore, there is an urgent need for studies on amodiaquine safety and tolerability during pregnancy since current data are not sufficient to recommend its use during pregnancy, particularly as intermittent preventive treatment.