Estimating the Economic and Clinical Value of Introducing Ceftazidime/Avibactam into Antimicrobial Practice in Japan: A Dynamic Modelling Study

Estimating the value of new antibiotic treatment strategies in Zhejiang province, China: cost-effectiveness analysis based on a validated dynamic model

OBJECTIVES

This analysis aims to better reflect the value of new antibiotic treatment strategies, thereby informing clinical antibiotic use, antimicrobial reimbursement and/or hospital formulary decision-making in China.

DESIGN

We adapted a published and validated dynamic disease transmission and cost-effectiveness model to evaluate the clinical and economic outcomes of introducing a new antibiotic, ceftazidime/avibactam (CAZ-AVI) for treating resistant infections in Zhejiang province, China. Outcomes were assessed over a 10-year infectious period and an annual discount rate of 5%. Costs were extracted from the hospital's Health Information System (HIS) and obtained after data cleaning, aggregation and discounting.

SETTING

The Chinese healthcare system perspective.

PARTICIPANTS

10 905 patients in a Chinese tier-3 hospital from 2018 to 2021 with any of the three common infections (complicated intra-abdominal infection (cIAI), hospital-acquired/ventilator-associated pneumonia (HAP/VAP) and infections with limited treatment options (LTO)) caused by three common resistant pathogens (Escherichia coli, Klebsiella spp. and Pseudomonas aeruginosa).

INTERVENTIONS

(1) Current treatment strategy (piperacillin-tazobactam (pip/taz) and meropenem); (2) CAZ-AVI at the third line; (3) CAZ-AVI at the second line; (4) CAZ-AVI at the first line; (5) CAZ/AVI first line, two lines diversified (i.e., equal pip/taz and CAZ-AVI at the first line; meropenem at the last line) and (6) CAZ/AVI first line, all-lines diversified.

PRIMARY OUTCOME MEASURES

Quality-adjusted life years (QALYs) lost, hospitalisation costs and incremental net monetary benefit (INMB) were used to assess cost-effectiveness.

RESULTS

Over 10 years, the introduction of CAZ-AVI to the current treatment strategy led to lower hospitalisation costs and more QALYs across all five treatment strategies, with between 68 284 and 78 571 QALYs gained whilst saving up to US$236.37 for each additional QALY gained. The INMB of introducing CAZ-AVI is estimated up to US$3 550 811 878.

CONCLUSIONS

Introducing CAZ-AVI had a positive impact on clinical and economic outcomes for treating antimicrobial resistance, and diversifying the antibiotics use early in the treatment might yield the best benefits.

Quenching of quorum sensing in multi-drug resistant Pseudomonas aeruginosa: insights on halo-bacterial metabolites and gamma irradiation as channels inhibitors

BACKGROUND

Anti-virulence therapy is a promising strategy to treat multi-drug resistant (MDR) pathogens. Pseudomonas aeruginosa is a potent opportunistic pathogen because of an array of virulence factors that are regulated by quorum sensing systems.

METHODS

The virulence features of four multi-drug resistant P. aeruginosa strains were investigated upon exposure to the sub-lethal dose of gamma rays (1 kGy), and sub-inhibitory concentrations of bioactive metabolites recovered from local halophilic strains in comparison to control. Then, the gene expression of AHL-mediated quorum sensing systems (las/rhl) was quantitatively determined in treated and untreated groups by real-time PCR.

RESULTS

The bioactive metabolites recovered from halophilic strains previously isolated from saline ecosystems were identified as Halomonas cupida (Halo-Rt1), H. elongate (Halo-Rt2), Vigibacillus natechei (Halo-Rt3), Sediminibacillus terrae (Halo-Rt4) and H. almeriensis (Halo-Rt5). Results revealed that both gamma irradiation and bioactive metabolites significantly reduced the virulence factors of the tested MDR strains. The bioactive metabolites showed a maximum efficiency for inhibiting biofilm formation and rhamnolipids production whereas the gamma irradiation succeeded in decreasing other virulence factors to lower levels in comparison to control. Quantitative-PCR results showed that AHL-mediated quorum sensing systems (las/rhl) in P. aeruginosa strains were downregulated either by halo-bacterial metabolites or gamma irradiation in all treatments except the upregulation of both lasI internal gene and rhlR intact gene in P. aeruginosa NCR-RT3 and both rhlI internal gene and rhlR intact gene in P. aeruginosa U3 by nearly two folds or more upon exposure to gamma irradiation. The most potent result was observed in the expression of lasI internal gene that was downregulated by more than ninety folds in P. aeruginosa NCR-RT2 after treatment with metabolites of S. terrae (Halo-Rt4). Analyzing metabolites recovered from H. cupida (Halo-Rt1) and H. elongate (Halo-Rt2) using LC-ESI-MS/MS revealed many chemical compounds that have quorum quenching properties including glabrol, 5,8-dimethoxyquinoline-2-carbaldehyde, linoleoyl ethanolamide, agelasine, penigequinolones derivatives, berberine, tetracosanoic acid, and liquidambaric lactone in the former halophile and phloretin, lycoctonine, fucoxanthin, and crassicauline A in the latter one.

CONCLUSION

QS inhibitors can significantly reduce the pathogenicity of MDR P. aeruginosa strains; and thus can be an effective and successful strategy for treating antibiotic resistant traits.

Quantifying the Economic and Clinical Value of Reducing Antimicrobial Resistance in Gram-negative Pathogens Causing Hospital-Acquired Infections in Australia

INTRODUCTION

Antimicrobial resistance (AMR) is a global public health challenge requiring a global response to which Australia has issued a National Antimicrobial Resistance Strategy. The necessity for continued-development of new effective antimicrobials is required to tackle this immediate health threat is clear, but current market conditions may undervalue antimicrobials. We aimed to estimate the health-economic benefits of reducing AMR levels for drug-resistant gram-negative pathogens in Australia, to inform health policy decision-making.

METHODS

A published and validated-dynamic health economic model was adapted to the Australian setting. Over a 10-year time horizon, the model estimates the clinical and economic outcomes associated with reducing current AMR levels, by up to 95%, of three gram-negative pathogens in three hospital-acquired infections, from the perspective of healthcare payers. A willingness-to-pay threshold of AUD$15,000-$45,000 per quality-adjusted life-year (QALY) gained and a 5% discount rate (for costs and benefits) were applied.

RESULTS

Over ten years, reducing AMR for gram-negative pathogens in Australia is associated with up to 10,251 life-years and 8924 QALYs gained, 9041 bed-days saved and 6644 defined-daily doses of antibiotics avoided. The resulting savings are estimated to be $10.5 million in hospitalisation costs, and the monetary benefit at up to $412.1 million.

DISCUSSION

Our results demonstrate the clinical and economic value of reducing AMR impact in Australia. Of note, since our analysis only considered a limited number of pathogens in the hospital setting only and for a limited number of infection types, the benefits of counteracting AMR are likely to extend well beyond the ones demonstrated here.

CONCLUSION

These estimates demonstrate the consequences of failure to combat AMR in the Australian context. The benefits in mortality and health system costs justify consideration of innovative reimbursement schemes to encourage the development and commercialisation of new effective antimicrobials.

An Economic Evaluation Estimating the Clinical and Economic Burden of Increased Vancomycin-Resistant Enterococcus faecium Infection Incidence in Japan

INTRODUCTION

While incidence rates of vancomycin-resistant Enterococcus faecium have remained comparatively low in Japan, there have been increasing reports of more vancomycin-resistant Enterococcus (VRE) outbreaks, requiring costly measures to contain. Increased incidence of VRE in Japan may lead to more frequent and harder to contain outbreaks with current control measures, causing a significant burden to the healthcare system in Japan. This study aimed to demonstrate the clinical and economic burden of vancomycin-resistant E. faecium infections to the Japanese healthcare system and the impact of increasing rates of vancomycin resistance.

METHODS

A de novo deterministic analytic model was developed to assess the health economic outcomes of treating hospital-acquired VRE infections; patients are treated according to a two-line treatment strategy, dependent on their resistance status. The model considers hospitalisation costs and the additional cost of infection control. Scenarios investigated the current burden of VRE infections and the additional burden of increased incidence of VRE. Outcomes were assessed over a 1-year and 10-year time horizon from a healthcare payer's perspective in a Japanese setting. Quality-adjusted life years (QALYs) were valued with a willingness-to-pay threshold of ¥5,000,000 ($38,023), and costs and benefits were discounted at a rate of 2%.

RESULTS

Current VRE incidence levels in enterococcal infections in Japan equates to ¥130,209,933,636 ($996,204,669) in associated costs and a loss of 185,361 life years (LYs) and 165,934 QALYs over 10 years. A three-fold increase (1.83%) is associated with an additional ¥4,745,059,504 ($36,084,651) in total costs on top of the current cost burden as well as an additional loss of 683 LYs over a lifetime, corresponding to 616 QALYs lost.

CONCLUSION

Despite low incidence rates, VRE infections already represent a substantial economic burden to the Japanese healthcare system. The substantial increase in costs associated with a higher incidence of VRE infections could result in a significant economic challenge for Japan.