Incorporating economies of scale in the cost estimation in economic evaluation of PCV and HPV vaccination programmes in the Philippines: a game changer?

Comprehensive observational study evaluating the enduring effectiveness of 4CMenB, the meningococcal B vaccine against gonococcal infections in the Northern Territory and South Australia, Australia: study protocol

INTRODUCTION

The effectiveness of antibiotics for treating gonococcal infections is compromised due to escalating antibiotic resistance; and the development of an effective gonococcal vaccine has been challenging. Emerging evidence suggests that the licensed meningococcal B (MenB) vaccine, 4CMenB is effective against gonococcal infections due to cross-reacting antibodies and 95% genetic homology between the two bacteria, Neisseria meningitidis and Neisseria gonorrhoeae, that cause the diseases. This project aims to undertake epidemiological and genomic surveillance to evaluate the long-term protection of the 4CMenB vaccine against gonococcal infections in the Northern Territory (NT) and South Australia (SA), and to determine the potential benefit of a booster vaccine doses to provide longer-term protection against gonococcal infections.

METHODS AND ANALYSES

This observational study will provide long-term evaluation results of the effectiveness of the 4CMenB vaccine against gonococcal infections at 4-7 years post 4CMenB programme implementation. Routine notifiable disease notifications will be the basis for assessing the impact of the vaccine on gonococcal infections. Pathology laboratories will provide data on the number and percentage of N. gonorrhoeae positive tests relative to all tests administered and will coordinate molecular sequencing for isolates. Genome sequencing results will be provided by SA Pathology and Territory Pathology/New South Wales Health Pathology, and linked with notification data by SA Health and NT Health. There are limitations in observational studies including the potential for confounding. Confounders will be analysed separately for each outcome/comparison.

ETHICS AND DISSEMINATION

The protocol and all study documents have been reviewed and approved by the SA Department for Health and Well-being Human Research Ethics Committee (HREC/2022/HRE00308), and the evaluation will commence in the NT on receipt of approval from the NT Health and Menzies School of Health Research Human Research Ethics Committee. Results will be published in peer-reviewed journals and presented at scientific meetings and public forums.

Cost-effectiveness of a 12 country-intervention to scale up short course TB preventive therapy among people living with HIV

INTRODUCTION

In 2017, the Aurum Institute, with support from Unitaid, launched an initiative to expand short-course therapy for the prevention of tuberculosis (TB) in 12 high-burden countries. This study aimed to investigate the importance of "catalytic" effects beyond the original project timeframe when estimating cost-effectiveness of such large investments.

METHODS

We estimated the cost-effectiveness of the IMPAACT4TB (I4TB) initiative from a health system perspective, using a 10-year time horizon. We first conservatively estimated costs using a "top-down" approach considering only the direct health benefits of providing TB preventive therapy to people initiating antiretroviral therapy (ART) through I4TB activities. We then re-estimated the incremental cost-effectiveness of I4TB incorporating the costs and health benefits of potential catalytic effects beyond the program itself.

RESULTS

We estimated that TB preventive therapy through the I4TB initiative alone would prevent 14 201 cases of active TB and 1562 TB deaths over 10 years with an up-front investment of $52.5 million; the estimated incremental cost-effectiveness was $1580 per disability-adjusted life year (DALY) averted. If this initiative could achieve its desired catalytic effects, an additional 375 648 cases and 41 321 deaths could be averted, at an incremental cost of $546 million and cost-effectiveness of $713 per DALY averted.

CONCLUSIONS

Our findings provide donors with reasonable evidence of value for money to support investment in short-course TB preventive therapy for people initiating ART in high-burden settings. Our study also illustrates the importance of considering long-term secondary ("catalytic") effects when evaluating the cost-effectiveness of large-scale initiatives designed to change a global policy landscape.