Development of an agent-based model to assess the impact of substandard and falsified anti-malarials: Uganda case study

Improving malaria case management with artemisinin-based combination therapies and malaria rapid diagnostic tests in private medicine retail outlets in sub-Saharan Africa: A systematic review

Private medicine retailers (PMRs) such as pharmacies and drug stores account for a substantial share of treatment-seeking for fever and malaria, but there are widespread concerns about quality of care, including inadequate access to malaria rapid diagnostic tests (RDTs) and artemisinin-based combination therapies (ACTs). This review synthesizes evidence on the effectiveness of interventions to improve malaria case management in PMRs in sub-Saharan Africa (PROSPERO #2021:CRD42021253564). We included quantitative studies evaluating interventions supporting RDT and/or ACT sales by PMR staff, with a historical or contemporaneous control group, and outcomes related to care received. We searched Medline Ovid, Embase Ovid, Global Health Ovid, Econlit Ovid and the Cochrane Library; unpublished studies were identified by contacting key informants. We conducted a narrative synthesis by intervention category. We included 41 papers, relating to 34 studies. There was strong evidence that small and large-scale ACT subsidy programmes (without RDTs) increased the market share of quality-assured ACT in PMRs, including among rural and poorer groups, with increases of over 30 percentage points in most settings. Interventions to introduce or enhance RDT use in PMRs led to RDT uptake among febrile clients of over two-thirds and dispensing according to RDT result of over three quarters, though some studies had much poorer results. Introducing Integrated Community Case Management (iCCM) was also effective in improving malaria case management. However, there were no eligible studies on RDT or iCCM implementation at large scale. There was limited evidence that PMR accreditation (without RDTs) increased ACT uptake. Key evidence gaps include evaluations of RDTs and iCCM at large scale, evaluations of interventions including use of digital technologies, and robust studies of accreditation and other broader PMR interventions.

Health, Economic, and Social Impacts of Substandard and Falsified Medicines in Low- and Middle-Income Countries: A Systematic Review of Methodological Approaches

Little is known about the adverse health, economic, and social impacts of substandard and falsified medicines (SFMs). This systematic review aimed to identify the methods used in studies to measure the impact of SFMs in low- and middle-income countries (LMICs), summarize their findings, and identify gaps in the reviewed literature. A search of eight databases for published papers, and a manual search of references in the relevant literature were conducted using synonyms of SFMs and LMICs. Studies in the English language that estimated the health, social, or economic impacts of SFMs in LMICs published before June 17, 2022 were considered eligible. Search results generated 1,078 articles, and 11 studies were included after screening and quality assessment. All included studies focused on countries in sub-Saharan Africa. Six studies used the Substandard and Falsified Antimalarials Research Impact model to estimate the impact of SFMs. This model is an important contribution. However, it is technically challenging and data demanding, which poses challenges to its adoption by national academics and policymakers alike. The included studies estimate that substandard and falsified antimalarial medicines can account from 10% to ∼40% of total annual malaria costs, and SFMs affect rural and poor populations disproportionately. Evidence on the impact of SFMs is limited in general and nonexistent regarding social outcomes. Further research needs to focus on practical methods that can serve local authorities without major investments in terms of technical capacity and data collection.

Pharmacopeial quality of artemether-lumefantrine anti-malarial agents in Uganda

BACKGROUND

Substandard anti-malarial agents pose a significant challenge to effective malaria control and elimination efforts especially in sub-Saharan Africa. The quality of anti-malarials in most low-and-middle income countries (LMICs) is affected by several factors including inadequate regulation and limited resources. In this study, the pharmacopeial quality of artemether-lumefantrine (AL) in low and high malaria transmission settings in Uganda was assessed.

METHODS

This was a cross-sectional study conducted among randomly selected private drug outlets. The AL anti-malarials available in drug outlets were purchased using overt method. The samples were screened for quality using visual inspection, weight uniformity, content assay and dissolution tests. The assay test was done using liquid chromatography-mass spectrometry (LC-MS). The samples were considered substandard if the active pharmaceutical ingredient (API) content was outside 90-110% range of the label claim. Dissolution test was conducted following United States Pharmacopoeia (USP) method. Data was analysed using descriptive statistics and presented as means with standard deviations, frequencies, and proportions. Correlation between medicine quality and independent variables was determined using Fisher's exact test of independence at 95% level of significance.

RESULTS

A total of 74 AL anti-malarial samples were purchased from high (49/74; 66.2%) and low (25/74; 33.8%) malaria transmission settings. The most common batch of AL was LONART, 32.4% (24/74), with 33.8% (25/74) being 'Green leaf'. Overall prevalence of substandard quality artemether-lumefantrine was 18.9% (14/74; 95% CI: 11.4-29.7). Substandard quality AL was significantly associated with setting (p = 0.002). A total of 10 samples (13.5%) failed artemether content assay test while, 4 samples (5.4%, 4/74) failed the lumefantrine assay test. One sample from a high malaria transmission setting failed both artemether and lumefantrine assay content test. Of the samples that failed artemether assay test, 90% had low (< 90%) artemether content. All the samples passed visual inspection and dissolution tests.

CONCLUSION

Artemether-lumefantrine agents, the recommended first-line treatment for uncomplicated malaria with APIs outside the recommended pharmacopeial content assay limit is common especially in high malaria transmission settings. There is need for continuous surveillance and monitoring of the quality of artemisinin-based anti-malarials across the country by the drug regulatory agency.

Modeling the Health and Economic Impact of Substandard and Falsified Medicines: A Review of Existing Models and Approaches

Substandard and falsified medicines are harmful to patients, causing prolonged illness, side effects, and preventable deaths. Moreover, they have an impact on the health system and society more broadly by leading to additional care, higher disease burden, productivity losses and loss of trust in health care. Models that estimate the health and economic impacts of substandard and falsified medicines can be useful for regulators to contextualize the problem and to make an economic case for solutions. Yet these models have not been systematically catalogued to date. We reviewed existing models that estimate the health and economic impact of substandard and falsified medicines to describe the varying modeling approaches and gaps in knowledge. We compared model characteristics, data sources, assumptions, and limitations. Seven models were identified. The models assessed the impact of antimalarial (n = 5) or antibiotic (n = 2) quality at a national (n = 4), regional (n = 2), or global (n = 1) level. Most models conducted uncertainty analysis and provided ranges around potential outcomes. We found that models are lacking for other medicines, few countries' data have been analyzed, and capturing population heterogeneity remains a challenge. Providing the best estimates of the impact of substandard and falsified medicines on a level that is actionable for decision-makers is important. To enable this, research on the impact of substandard and falsified medicines should be expanded to more medicine types and classes and tailored to more countries that are affected, with greater specificity.

Assessing the Impact of Substandard and Falsified Antimalarials in Benin

Substandard and falsified antimalarials contribute to the global malaria burden by increasing the risk of treatment failures, adverse events, unnecessary health expenditures, and avertable deaths, yet no study has examined this impact in western francophone Africa to date. In Benin, where malaria remains endemic and is the leading cause of mortality among children younger than 5 years, there is a lack of robust data to combat the issue effectively and inform policy decisions. We adapted the Substandard and Falsified Antimalarial Research Impact model to assess the health and economic impact of poor-quality antimalarials in this population. The model simulates population characteristics, malaria infection, care-seeking behavior, disease progression, treatment outcomes, and associated costs of malaria. We estimated approximately 1.8 million cases of malaria in Benin among children younger than 5 years, which cost $193 million (95% CI, $192-$193 million) in treatment costs and productivity losses annually. Substandard and falsified antimalarials were responsible for 11% (n = 693) of deaths and nearly $20.8 million in annual costs. Moreover, we found that replacing all antimalarials with quality-ensured artemisinin combination therapies (ACTs) could result in $29.6 million in cost savings and prevent 1,038 deaths per year. These results highlight the value of improving access to quality-ensured artemisinin combination therapies for malaria treatment and increasing care-seeking in Benin. Policymakers and key stakeholders should use these findings to advocate for increased access to quality-ensured antimalarials, inform policies and interventions to improve health-care access and quality, and reduce the burden of malaria.

Implementation of field detection devices for antimalarial quality screening in Lao PDR-A cost-effectiveness analysis

Substandard and falsified (SF) antimalarials have devastating consequences including increased morbidity, mortality and economic losses. Portable medicine quality screening devices are increasingly available, but whether their use for the detection of SF antimalarials is cost-effective is not known. We evaluated the cost-effectiveness of introducing such devices in post-market surveillance in pharmacies in Laos, conservatively focusing on their outcome in detecting SF artemisinin-based combination therapies (ACTs). We simulated the deployment of six portable screening devices: two handheld near-infrared [MicroPHAZIR RX, NIR-S-G1], two handheld Raman [Progeny, TruScan RM]; one portable mid-infrared [4500a FTIR] spectrometers, and single-use disposable paper analytical devices [PADs]. We considered two scenarios with high and low levels of SF ACTs. Different sampling strategies in which medicine inspectors would test 1, 2, or 3 sample(s) of each brand of ACT were evaluated. Costs of inspection including device procurement, inspector time, reagents, reference testing, and replacement with genuine ACTs were estimated. Outcomes were measured as disability adjusted life years (DALYs) and incremental cost-effectiveness ratios were estimated for each device compared with a baseline of visual inspections alone. In the scenario with high levels of SF ACTs, all devices were cost-effective with a 1-sample strategy. In the scenario of low levels of SF ACTs, only four devices (MicroPHAZIR RX, 4500a FTIR, NIR-S-G1, and PADs) were cost-effective with a 1-sample strategy. In the multi-way comparative analysis, in both scenarios the NIR-S-G1 testing 2 samples was the most cost-effective option. Routine inspection of ACT quality using portable screening devices is likely to be cost-effective in the Laos context. This work should encourage policy-makers or regulators to further investigate investment in portable screening devices to detect SF medicines and reduce their associated undesired health and economic burdens.

Impact of substandard and falsified antimalarials in Zambia: application of the SAFARI model

BACKGROUND

Many countries are striving to become malaria-free, but global reduction in case estimates has stagnated in recent years. Substandard and falsified medicines may contribute to this lack of progress. Zambia aims to eliminate their annual burden of 1.2 million pediatric malaria cases and 2500 child deaths due to malaria. We examined the health and economic impact of poor-quality antimalarials in Zambia.

METHODS

An agent-based model, Substandard and Falsified Antimalarial Research Impact (SAFARI), was modified and applied to Zambia. The model was developed to simulate population characteristics, malaria incidence, patient care-seeking, disease progression, treatment outcomes, and associated costs of malaria for children under age five. Zambia-specific demographic, epidemiological, and cost inputs were extracted from the literature. Simulations were run to estimate the health and economic impact of poor-quality antimalarials, the effect of potential artemisinin resistance, and six additional malaria focused policy interventions.

RESULTS

We simulated annual malaria cases among Zambian children under five. At baseline, we found 2610 deaths resulting in $141.5 million in annual economic burden of malaria. We estimated that elimination of substandard and falsified antimalarials would result in an 8.1% (n = 213) reduction in under-five deaths, prevent 937 hospitalizations, and realize $8.5 million in economic savings, annually. Potential artemisinin resistance could further increase deaths by 6.3% (n = 166) and cost an additional $9.7 million every year.

CONCLUSIONS

Eliminating substandard and falsified antimalarials is an important step towards a malaria-free Zambia. Beyond the dissemination of insecticide-treated bed nets, indoor residual spraying, and other malaria control measures, attention must also be paid to assure the quality of antimalarial treatments.

Importance of medicine quality in achieving universal health coverage

OBJECTIVE

To assess the importance of ensuring medicine quality in order to achieve universal health coverage (UHC).

METHODS

We developed a systems map connecting medicines quality assurance systems with UHC goals to illustrate the ensuing impact of quality-assured medicines in the implementation of UHC. The association between UHC and medicine quality was further examined in the context of essential medicines in low- and middle-income countries (LMICs) by analyzing data on reported prevalence of substandard and falsified essential medicines and established indicators for UHC. Finally, we examined the health and economic savings of improving antimalarial quality in four countries in sub-Saharan Africa: the Democratic Republic of the Congo (DRC), Nigeria, Uganda, and Zambia.

FINDINGS

A systems perspective demonstrates how quality assurance of medicines supports dimensions of UHC. Across 63 LMICs, the reported prevalence of substandard and falsified essential medicines was found to be negatively associated with both an indicator for coverage of essential services (p = 0.05) and with an indicator for government effectiveness (p = 0.04). We estimated that investing in improving the quality of antimalarials by 10% would result in annual savings of $8.3 million in Zambia, $14 million in Uganda, $79 million in two DRC regions, and $598 million in Nigeria, and was more impactful compared to other potential investments we examined. Costs of substandard and falsified antimalarials per malaria case ranged from $7 to $86, while costs per death due to poor-quality antimalarials ranged from $14,000 to $72,000.

CONCLUSION

Medicines quality assurance systems play a critical role in reaching UHC goals. By ensuring the quality of essential medicines, they help deliver effective treatments that lead to less illness and result in health care savings that can be reinvested towards UHC.

Tackling the blind spot of poor-quality medicines in Universal Health Coverage

BACKGROUND

Universal Health Coverage (UHC) is challenged by the prevalence of poor-quality medicines, those that either do not meet required specifications (substandard) or are outrightly fraudulent (falsified), especially in Low- and Middle-Income Countries, LMICs. Whereas poor-quality medicines are a significant burden in these countries, medicine quality still remains a neglected component of UHC programs. This article describes key barriers to quality medicines and presents five select approaches leveraging the scale-up of UHC for medicine quality assurance.

MAIN BODY

Barriers to medicine quality assurance, while numerous, are described in five key inter-related domains as: low political priority, weak regulatory systems capacity, poor access to accredited facilities and licensed outlets, medicine manufacturing and other supply-chain challenges, and lack of public awareness. Five select approaches for leveraging the scale-up of UHC for medicine quality assurance in LMICs are (1): political commitment (2) strengthening the capacity of regulatory authorities and investment in detection technologies as part of national security (3); licensing of medicines outlets and expanding pharmacovigilance (4); strengthening the supply-chain; and (5) public awareness and participation.

CONCLUSIONS

Unchecked, poor-quality medicines can jeopardize UHC. National governments in LMICs need to prioritize medicine quality assurance through enforcing policies, regulatory strengthening and investments in technologies. Healthcare facilities and insurance schemes under UHC also play critical roles through incorporating medicine quality assurance into procurement practices and by promoting awareness among beneficiaries. Tackling medicine quality with a committed systems approach will enhance progress towards UHC implementation.

Poor-quality antimalarials further health inequities in Uganda

Substandard and falsified medications are a major threat to public health, directly increasing the risk of treatment failure, antimicrobial resistance, morbidity, mortality and health expenditures. While antimalarial medicines are one of the most common to be of poor quality in low- and middle-income countries, their distributional impact has not been examined. This study assessed the health equity impact of substandard and falsified antimalarials among children under five in Uganda. Using a probabilistic agent-based model of paediatric malaria infection (Substandard and Falsified Antimalarial Research Impact, SAFARI model), we examine the present day distribution of the burden of poor-quality antimalarials by socio-economic status and urban/rural settings, and simulate supply chain, policy and patient education interventions. Patients incur US$26.1 million (7.8%) of the estimated total annual economic burden of substandard and falsified antimalarials, including $2.3 million (9.1%) in direct costs and $23.8 million (7.7%) in productivity losses due to early death. Poor-quality antimalarials annually cost $2.9 million to the government. The burden of the health and economic impact of malaria and poor-quality antimalarials predominantly rests on the poor (concentration index −0.28) and rural populations (98%). The number of deaths among the poorest wealth quintile due to substandard and falsified antimalarials was 12.7 times that of the wealthiest quintile, and the poor paid 12.1 times as much per person in out-of-pocket payments. Rural populations experienced 97.9% of the deaths due to poor-quality antimalarials, and paid 10.7 times as much annually in out-of-pocket expenses compared with urban populations. Our simulations demonstrated that interventions to improve medicine quality could have the greatest impact at reducing inequities, and improving adherence to antimalarials could have the largest economic impact. Substandard and falsified antimalarials have a significant health and economic impact, with greater burden of deaths, disability and costs on poor and rural populations, contributing to health inequities in Uganda.

Falsified and Substandard Drugs: Stopping the Pandemic

Falsified and substandard medicines are associated with tens of thousands of deaths, mainly in young children in poor countries. Poor-quality drugs exact an annual economic toll of up to US$200 billion and contribute to the increasing peril of antimicrobial resistance. The WHO has emerged recently as the global leader in the battle against poor-quality drugs, and pharmaceutical companies have increased their roles in assuring the integrity of drug supply chains. Despite advances in drug quality surveillance and detection technology, more efforts are urgently required in research, policy, and field monitoring to halt the pandemic of bad drugs. In addition to strengthening international and national pharmaceutical governance, in part by national implementation of the Model Law on Medicines and Crime, a quantifiable Sustainable Development Goal target and an international convention to insure drug quality and safety are urgent priorities.

The economic impact of substandard and falsified antimalarial medications in Nigeria

INTRODUCTION

Substandard and falsified medications pose significant risks to global health. Nearly one in five antimalarials circulating in low- and middle-income countries are substandard or falsified. We assessed the health and economic impact of substandard and falsified antimalarials on children under five in Nigeria, where malaria is endemic and poor-quality medications are commonplace.

METHODS

We developed a dynamic agent-based SAFARI (Substandard and Falsified Antimalarial Research Impact) model to capture the impact of antimalarial use in Nigeria. The model simulated children with background characteristics, malaria infections, patient care-seeking, disease progression, treatment outcomes, and incurred costs. Using scenario analyses, we simulated the impact of substandard and falsified medicines, antimalarial resistance, as well as possible interventions to improve the quality of treatment, reduce stock-outs, and educate caregivers about antimalarial quality.

RESULTS

We estimated that poor quality antimalarials are responsible for 12,300 deaths and $892 million ($890-$893 million) in costs annually in Nigeria. If antimalarial resistance develops, we simulated that current costs of malaria could increase by $839 million (11% increase, $837-$841 million). The northern regions of Nigeria have a greater burden as compared to the southern regions, with 9,700 deaths and $698 million ($697-$700 million) in total economic losses annually due to substandard and falsified antimalarials. Furthermore, our scenario analyses demonstrated that possible interventions-such as removing stock-outs in all facilities ($1.11 billion), having only ACTs available for treatment ($594 million), and 20% more patients seeking care ($469 million)-can save hundreds of millions in costs annually in Nigeria.

CONCLUSIONS

The results highlight the significant health and economic burden of poor quality antimalarials in Nigeria, and the impact of potential interventions to counter them. In order to reduce the burden of malaria and prevent antimalarials from developing resistance, policymakers and donors must understand the problem and implement interventions to reduce the impact of ineffective and harmful antimalarials.