(Inter)nationalising the antibiotic research and development pipeline

In this Personal View, we critically examine the wider context of international efforts to stimulate commercial antibiotic research and development via public-private initiatives. Despite these efforts, antibiotics remain a global resource without an international support structure that is commensurate to the risks from antibiotic-resistant infections and the long-term nature of required solutions. To protect this resource, we propose a two-pronged antibiotic research and development strategy based on a short-term strengthening of incentives (such as market entry rewards) to maximise the delivery of existing opportunities in the pipeline, and on a concurrent medium-term to long-term establishment of a global, publicly funded antibiotic research and development institute. Designed sustainably to deliver novel and first-in-class antibiotics targeting key human health gaps, the institute and its staff would become a global resource that, unlike the private pharmaceutical sector, would be managed as an open science platform. Our model of internationalised public research and development would maximise scientific synergy and cross-fertilisation, minimise replication of effort, acquire and preserve existing know-how, and ensure equitable and sustainable access to novel and effective antibiotics. Its genuinely global focus would also help counteract tendencies to equate donor with global health priorities. Our proposal is not radical. Historical precedent and developments in other research areas show that sustained international funding of publicly owned research can hasten the delivery of critically needed drugs and lower barriers to access.

Targeting of Nanotherapeutics to Infection Sites for Antimicrobial Therapy

Bacterial infections cause a wide range of host immune disorders, resulting in local and systemic tissue damage. Antibiotics are pharmacological interventions for treating bacterial infections, but increased antimicrobial resistance and the delayed development of new antibiotics have led to a major global health threat, the so-called "superbugs". Bacterial infections consist of two processes: pathogen invasion and host immune responses. Developing nanotherapeutics to target these two pathways may be effective for eliminating bacteria and restoring host homeostasis, thus possibly finding new treatments for bacterial infections. This review offers new approaches for developing nanotherapeutics based on the pathogenesis of infectious diseases. We have discussed how nanoparticles target infectious microenvironments (IMEs) and how they target phagocytes to deliver antibiotics to eliminate intracellular pathogens. We also review a new concept-host-directed therapy for bacterial infections, such as targeting immune cells for the delivery of anti-inflammatory agents and vaccine developments using bacterial membrane-derived nanovesicles. This review demonstrates the translational potential of nanomedicine for improving infectious disease treatments.

A framework for improved one health governance and policy making for antimicrobial use

There is a need to develop an evaluation framework to identify intervention priorities to reduce antimicrobial use (AMU) across clinical, agricultural and environmental settings. Antimicrobial resistance (AMR) can be conceptualised and therefore potentially managed in the same way as an environmental pollution problem. That is, over-use of antimicrobial medicines as inputs to human and animal health leads to unintended leakage of resistance genes that further combine with natural or intrinsic resistance in the environment. The diffuse nature of this leakage means that the private use decision is typically neither cognisant, nor made responsible for the wider social cost, which is the depletion of wider antibiotic effectiveness, a common pool resource or public good. To address this so-called market failure, some authors have suggested a potential to learn from similar management challenges encountered in the sphere of global climate change, specifically, capping use of medically important drugs analogous to limits set on greenhouse gas emissions. Drawing on experience of the economics of greenhouse gas mitigation, this paper explores a potential framework to develop AMU budgets based on a systematic comparative appraisal of the technical, economic, behavioural and policy feasibility of AMU reduction interventions across the One Health domains. The suggested framework responds to a call for global efforts to develop multi-dimensional metrics and a transparent focus to motivate research and policy, and ultimately to inform national and global AMR governance.

Time series analysis of antibacterial usage and bacterial resistance in China: observations from a tertiary hospital from 2014 to 2018

Purpose

To describe trends and correlation between antibacterial exposure and bacterial resistance from hospitalized patients in a hospital in southern China.

Patients and methods

This study used hospital-wide data regarding antimicrobial resistance and consumption between January 1, 2014 and December 31, 2018. Antibacterial consumption was expressed as antimicrobial use density (AUD). The changes in trends and associations between antibacterial utilization and resistance were analyzed using linear regression and time series analysis.

Results

The total AUD of all antimicrobials decreased year by year (50.66 in 2014 vs 44.28 in 2018, P=0.03). The annual use of antimicrobials, such as penicillins, monobactams, aminoglycosides, macrolides, and lincosamides, significantly decreased (P<0.05), while the annual use of quinolones and tetracyclines significantly increased (P<0.05). Among the top ten isolated bacteria, antimicrobial resistance trends of Escherichia coli, Pseudomonas aeruginosa, Candida albicans, Staphylococcus aureus, and Staphylococcus epidermidis significantly decreased (P<0.05). Significant positive correlation was found between AUD of carbapenems and resistance rate of Acinetobacter baumannii to imipenem (β=32.87, P<0.01), as well as the correlation between AUD of quinolones and resistance rate of Enterococcus faecium to levofloxacin (β=104.40, P<0.01).

Conclusion

The consumption of antibiotics and antibiotic resistance has been significantly improved in this tertiary hospital. Additionally, the efforts of China’s antibiotic management may be suggested by the relationship between indicated antibiotic resistance and consumption. However, overall AUD levels and poor control of the use of antibiotics, such as quinolones and tetracyclines, still require strengthened management.

Optimising trial designs to identify appropriate antibiotic treatment durations

BACKGROUND

For many infectious conditions, the optimal antibiotic course length remains unclear. The estimation of course length must consider the important trade-off between maximising short- and long-term efficacy and minimising antibiotic resistance and toxicity.

MAIN BODY

Evidence on optimal treatment durations should come from randomised controlled trials. However, most antibiotic randomised controlled trials compare two arbitrarily chosen durations. We argue that alternative trial designs, which allow allocation of patients to multiple different treatment durations, are needed to better identify optimal antibiotic durations. There are important considerations when deciding which design is most useful in identifying optimal treatment durations, including the ability to model the duration-response relationship (or duration-response 'curve'), the risk of allocation concealment bias, statistical efficiency, the possibility to rapidly drop arms that are clearly inferior, and the possibility of modelling the trade-off between multiple competing outcomes.

CONCLUSION

Multi-arm designs modelling duration-response curves with the possibility to drop inferior arms during the trial could provide more information about the optimal duration of antibiotic therapies than traditional head-to-head comparisons of limited numbers of durations, while minimising the probability of assigning trial participants to an ineffective treatment regimen.