Ethical considerations in deploying triple artemisinin-based combination therapies for malaria: An analysis of stakeholders’ perspectives in Burkina Faso and Nigeria

Antiplasmodial potential of isolated xanthones from Mesua ferrea Linn. roots: an in vitro and in silico molecular docking and pharmacokinetics study

BACKGROUND

Malaria is a major global health concern, particularly in tropical and subtropical countries. With growing resistance to first-line treatment with artemisinin, there is an urgent need to discover novel antimalarial drugs. Mesua ferrea Linn., a plant used in traditional medicine for various purposes, has previously been investigated by our research group for its cytotoxic properties. The objective of this study was to explore the compounds isolated from M. ferrea with regards to their potential antiplasmodial activity, their interaction with Plasmodium falciparum lactate dehydrogenase (PfLDH), a crucial enzyme for parasite survival, and their pharmacokinetic and toxicity profiles.

METHODS

The isolated compounds were assessed for in vitro antiplasmodial activity against a multidrug-resistant strain of P. falciparum K1 using a parasite lactate dehydrogenase (pLDH) assay. In vitro cytotoxicity against Vero cells was determined using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The interactions between the isolated compounds and the target enzyme PfLDH were investigated using molecular docking. Additionally, pharmacokinetic and toxicity properties were estimated using online web tools SwissADME and ProTox-II, respectively.

RESULTS

Among the seven compounds isolated from M. ferrea roots, rheediachromenoxanthone (5), which belongs to the pyranoxanthone class, demonstrated good in vitro antiplasmodial activity, with the IC50 being 19.93 µM. Additionally, there was no toxicity towards Vero cells (CC50 = 112.34 µM) and a selectivity index (SI) of 5.64. Molecular docking analysis revealed that compound (5) exhibited a strong binding affinity of - 8.6 kcal/mol towards PfLDH and was stabilized by forming hydrogen bonds with key amino acid residues, including ASP53, TYR85, and GLU122. Pharmacokinetic predictions indicated that compound (5) possessed favorable drug-like properties and desired pharmacokinetic characteristics. These include high absorption in the gastrointestinal tract, classification as a non-substrate of permeability glycoprotein (P-gp), non-inhibition of CYP2C19, ease of synthesis, a high predicted LD50 value of 4,000 mg/kg, and importantly, non-hepatotoxic, non-carcinogenic, and non-cytotoxic effects.

CONCLUSIONS

This study demonstrated that compounds isolated from M. ferrea exhibit activity against P. falciparum. Rheediachromenoxanthone has significant potential as a scaffold for the development of potent antimalarial drugs.

Interventions to address antimicrobial resistance: an ethical analysis of key tensions and how they apply in low- income and middle-income countries

Antimicrobial resistance (AMR) is a global health and one health problem. Efforts to mitigate the problem of AMR are challenging to implement due to unresolved ethical tensions. We present an in-depth ethical analysis of tensions that might hinder efforts to address AMR. First, there is a tension between access and excess in the current population: addressing lack of access requires facilitating use of antimicrobials for some populations, while addressing excessive use for other populations. Second, there is a tension between personal interests and a wider, shared interest in curbing AMR. These personal interests can be viewed from the perspective of individuals seeking care and healthcare providers whose livelihoods depend on using or selling antimicrobials and who profit from the sales and use of antimicrobials. Third, there is a tension between the interests of current populations and the interests of future generations. Last, there is a tension between addressing immediate health threats such as pandemics, and AMR as a 'silent', chronic threat. For each of these tensions, we apply 'descriptive ethics' methods that draw from existing evidence and our experiences living and working in low-income and middle-income countries to highlight how these ethical tensions apply in such settings.

Triple artemisinin-based combination therapy (TACT): advancing malaria control and eradication efforts

This paper examines the far-reaching implications of Triple Artemisinin-Based Combination Therapy (TACT) in the global battle against malaria. Artemisinin-Based Combination Therapy (ACT) is recognized for its cost-effectiveness, lower likelihood of adverse events, and widespread acceptance by patients and healthcare providers. However, TACT introduces novel dimensions to the fight against malaria that make them a superior choice in several aspects. TACT has been demonstrated to address resistance, offer a broader spectrum of action, reduce the risk of treatment failure, and can be tailored to meet regional needs, strengthening the global effort to combat malaria. However, maximizing these benefits of TACT depends on accessibility, particularly in resource-limited regions where malaria is most prevalent. Collaborative efforts among stakeholders, sustainable pricing strategies, efficient supply chains, and public-private partnerships are essential to ensure that TACT reaches needy populations. Moreover, dispelling prevalent malaria myths through health education campaigns is critical in this endeavour. The paper underscores the significance of collaborative initiatives and partnerships among governments, international organizations, research institutions, acadaemia, pharmaceutical companies, and local communities. Together, these efforts can pave the way for the acceptance, adoption, and success of TACT, ultimately advancing the global goal of a malaria-free world.

A framework for stakeholder engagement in the adoption of new anti-malarial treatments in Africa: a case study of Nigeria

BACKGROUND

Recent reports of artemisinin partial resistance from Rwanda and Uganda are worrisome and suggest a future policy change to adopt new anti-malarials. This is a case study on the evolution, adoption, and implementation of new anti-malarial treatment policies in Nigeria. The main objective is to provide perspectives to enhance the future uptake of new anti-malarials, with an emphasis on stakeholder engagement strategies.

METHODS

This case study is based on an analysis of policy documents and stakeholders' perspectives drawn from an empirical study conducted in Nigeria, 2019-2020. A mixed methods approach was adopted, including historical accounts, review of programme and policy documents, and 33 qualitative in-depth interviews and 6 focus group discussions.

RESULTS

Based on policy documents reviewed, the adoption of artemisinin-based combination therapy (ACT) in Nigeria was swift due to political will, funding and support from global developmental partners. However, the implementation of ACT was met with resistance from suppliers, distributors, prescribers, and end-users, attributed to market dynamics, costs and inadequate stakeholder engagement. Deployment of ACT in Nigeria witnessed increased developmental partner support, robust data generation, ACT case-management strengthening and evidence on anti-malarial use in severe malaria and antenatal care management. A framework for effective stakeholder engagement for the future adoption of new anti-malarial treatment strategies was proposed. The framework covers the pathway from generating evidence on drug efficacy, safety and uptake; to making treatment accessible and affordable to end-users. It addresses which stakeholders to engage with and the content of engagement strategies with key stakeholders at different levels of the transition process.

CONCLUSION

Early and staged engagement of stakeholders from global bodies to community level end-users is critical to the successful adoption and uptake of new anti-malarial treatment policies. A framework for these engagements was proposed as a contribution to enhancing the uptake of future anti-malarial strategies.