Dynamic transmission models and economic evaluations of pneumococcal conjugate vaccines: a quality appraisal and limitations

An Italian cost-utility analysis of 20-valent pneumococcal conjugate vaccine for routine vaccination in infants

BACKGROUND

Streptococcus pneumoniae represents a significant global public health threat, causing approximately 45 million lower respiratory tract infections and 350,000 deaths annually among children under 5 years of age. Conjugate pneumococcal vaccines (PCVs), such as PCV15 and PCV20, have been developed to mitigate this burden by providing protection against serotypes responsible for the disease. The present analysis aims to evaluate the cost-utility of PCV20 compared to PCV15 as a vaccination strategy for preventing pneumococcal diseases in children in Italy.

METHODS AND MATERIALS

A cost-utility analysis (CUA) was conducted using a static Markov model adapted to the Italian context to simulate the economic and clinical effects of vaccination over a 10-year time horizon. The study adopted the perspective of the Italian National Health Service (NHS), considering only direct healthcare costs. Deterministic and probabilistic sensitivity analyses were performed to explore parameter uncertainty.

RESULTS

The model showed that PCV20 is a dominant strategy compared to PCV15, generating cost savings of €6.45 million and a gain of 101,708 QALYs (quality-adjusted life years). These benefits are attributed to PCV20's broader serotype coverage, which significantly reduces the incidence of invasive and non-invasive pneumococcal diseases. Vaccination with PCV20 offers substantial clinical and economic advantages over PCV15.

CONCLUSIONS

The introduction of PCV20 as a vaccination strategy for children in Italy represents a cost-effective and clinically advantageous option. Its implementation can reduce the burden of pneumococcal disease and associated healthcare costs, improving public health outcomes and the economic efficiency of the healthcare system.

Validating the Predictions of a Dynamic Transmission Model Using Real-World Data from a Universal Varicella Vaccination Program in Germany

Dynamic transmission models (DTMs) have been used to estimate various aspects of the public health impact of varicella vaccination programs. The aim of this study was to validate the predictions of a DTM-developed using the typical approach to varicella modeling-using real-world data from a country with a long-term universal varicella vaccination (UVV) program and to assess the sensitivity of the predictions to changes in model input parameters. A compartmental, age-stratified DTM was developed using the settings corresponding to the existing UVV program in Germany. The model-predicted total number of varicella cases followed the same trend as observed in the reported data. The agreement between the simulations' results and the data was the highest for the age group most exposed to varicella (0-5 years old), while for other age groups, a decline in accuracy was observed. Sensitivity analyses identified the input parameters having a crucial impact on the model's long-term predictions. The results supported the reliability of the DTM for assessing the impact of varicella vaccination programs over the first decades after their introduction and provided an insight into how certain parameters and assumptions influence the model output and thus require careful evaluation in the studies of future varicella vaccination programs.

A dynamic transmission model for assessing the impact of pneumococcal vaccination in the United States

Streptococcus pneumoniae (SP) is a bacterial pathogen that kills more than 300,000 children every year across the globe. Multiple vaccines exist that prevent pneumococcal disease, with each vaccine covering a variable number of the more than 100 known serotypes. Due to the high effectiveness of these vaccines, each new pneumococcal conjugate vaccine (PCV) introduction has resulted in a decrease in vaccine-type disease and a shift in the serotype distribution towards non-vaccine types in a phenomenon called serotype replacement. Here, an age-structured compartmental model was created that reproduced historical carriage transmission dynamics in the United States and was used to evaluate the population-level impact of new vaccine introductions into the pediatric population. The model incorporates co-colonization and serotype competition, which drives replacement of the vaccine types by the non-vaccine types. The model was calibrated to historical age- and serotype-specific invasive pneumococcal disease (IPD) data from the United States. Vaccine-specific coverage and effectiveness were integrated in accordance with the recommended timelines for each age group. Demographic parameters were derived from US-population-specific databases, while population mixing patterns were informed by US-specific published literature on age-group based mixing matrices. The calibrated model was then used to project the epidemiological impact of PCV15, a 15-valent pneumococcal vaccine, compared with the status quo vaccination with PCV13 and demonstrated the value of added serotypes in PCV15. Projections revealed that PCV15 would reduce IPD incidence by 6.04% (range: 6.01% to 6.06%) over 10 years when compared to PCV13.

Cost-effectiveness of PCV20 to Prevent Pneumococcal Disease in the Pediatric Population: A German Societal Perspective Analysis

INTRODUCTION

Since 2009, a pneumococcal conjugate vaccine (PCV) covering 13 serotypes (PCV13) has been included by Germany's Standing Committee on Vaccinations for infants, resulting in major reductions in pneumococcal disease (PD). Higher-valent vaccines may further reduce PD burden. This cost-effectiveness analysis compared 20-valent PCV (PCV20) under a 3+1 schedule with 15-valent PCV (PCV15) and PCV13, both under 2+1 schedule, in Germany's pediatric population.

METHODS

A Markov model with annual cycles over a 10-year time horizon was adapted to simulate the clinical and economic impact of pediatric vaccination with PCV20 versus lower-valent PCVs in Germany. The model used PCV13 clinical effectiveness and impact studies as well as PCV7 efficacy studies for vaccine direct and indirect effect estimates. Epidemiologic, utility, and medical cost inputs were obtained from published sources. Benefits and costs were discounted at 3% from a German societal perspective. Outcomes included PD cases, deaths, costs, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratios (ICERs).

RESULTS

In the base case, PCV20 provided greater health benefits than PCV13, averting more cases of invasive pneumococcal disease (IPD; 15,301), hospitalized and non-hospitalized pneumonia (460,197 and 472,365, respectively), otitis media (531,634), and 59,265 deaths over 10 years. This resulted in 904,854 additional QALYs and a total cost saving of €2,393,263,611, making PCV20 a dominant strategy compared with PCV13. Compared to PCV15, PCV20 was estimated to avert an additional 11,334 IPD, 704,948 pneumonia, and 441,643 otitis media cases, as well as 41,596 deaths. PCV20 was associated with a higher QALY gain and lower cost (i.e., dominance) compared with PCV15. The robustness of the results was confirmed through scenario analyses as well as deterministic and probabilistic sensitivity analyses.

CONCLUSION

PCV20 3+1 dominated both PCV13 2+1 and PCV15 2+1 over 10 years. Replacing lower-valent PCVs with PCV20 would result in greater clinical and economic benefits, given PCV20's broader serotype coverage.

Higher-valency pneumococcal conjugate vaccines in older adults, taking into account indirect effects from childhood vaccination: a cost-effectiveness study for the Netherlands

BACKGROUND

New 15- and 20-valent pneumococcal vaccines (PCV15, PCV20) are available for both children and adults, while PCV21 for adults is in development. However, their cost-effectiveness for older adults, taking into account indirect protection and serotype replacement from a switch to PCV15 and PCV20 in childhood vaccination, remains unexamined.

METHODS

We used a static model for the Netherlands to assess the cost-effectiveness of different strategies with 23-valent pneumococcal polysaccharide vaccine (PPV23), PCV15, PCV20, and PCV21 for a 65-year-old cohort from a societal perspective, over a 15-year time horizon. Childhood vaccination was varied from PCV10 to PCV13, PCV15, and PCV20. Indirect protection was assumed to reduce the incidence of vaccine serotypes in older adults by 80% (except for serotype 3, no effect), completely offset by an increase in non-vaccine serotype incidence due to serotype replacement.

RESULTS

Indirect effects from childhood vaccination reduced the cost-effectiveness of vaccination of older adults, depending on the serotype overlap between the vaccines. With PCV10, PCV13, or PCV15 in children, PCV20 was more effective and less costly for older adults than PPV23 and PCV15. PCV20 costs approximately €10,000 per quality-adjusted life year (QALY) gained compared to no pneumococcal vaccination, which falls below the conventional Dutch €20,000/QALY gained threshold. However, with PCV20 in children, PCV20 was no longer considered cost-effective for older adults, costing €22,550/QALY gained. As indirect effects progressed over time, the cost-effectiveness of PCV20 for older adults further diminished for newly vaccinated cohorts. PPV23 was more cost-effective than PCV20 for cohorts vaccinated 3 years after the switch to PCV20 in children. PCV21 offered the most QALY gains, and its cost-effectiveness was minimally affected by indirect effects due to its coverage of 11 different serotypes compared to PCV20.

CONCLUSIONS

For long-term cost-effectiveness in the Netherlands, the pneumococcal vaccine for older adults should either include invasive serotypes not covered by childhood vaccination or become more affordable than its current pricing for individual use.

Cost-effectiveness analysis of 20-valent pneumococcal conjugate vaccine for routine pediatric vaccination programs in Japan

BACKGROUND

The Japanese National Immunization Program currently includes the pediatric 13 valent pneumococcal conjugate vaccine (PCV13) to prevent pneumococcal infections. We aimed to evaluate the cost-effectiveness of 20-valent PCV (PCV20) as a pediatric vaccine versus PCV13.

METHODS

A decision-analytic Markov model was used to estimate expected costs, quality-adjusted life-years (QALYs), and prevented cases and deaths caused by invasive pneumococcal disease, pneumonia, and acute otitis media over a ten-year time horizon from the societal and healthcare payer perspectives.

RESULTS

PCV20 was dominant, i.e. less costly and more effective, over PCV13 (gained 294,599 QALYs and reduced Japanese yen [JPY] 352.6 billion [2.6 billion United States dollars, USD] from the societal perspective and JPY 178.9 billion [USD 1.4 billion] from the payer perspective). Sensitivity and scenario analyses validated the robustness of the base scenario results. When comparing PCV20 with PCV13, the threshold analysis revealed an incremental cost-effectiveness ratio that was within the threshold value (JPY 5 million/QALY) at a maximum acquisition cost of JPY 74,033 [USD 563] (societal perspective) and JPY 67,758 [USD 515] (payer perspective).

CONCLUSIONS

As a pediatric vaccine, PCV20 was dominant over PCV13 regardless of the study perspective.

Economic evaluations of 13-valent pneumococcal conjugate vaccine: a systematic review

INTRODUCTION

Studies on economic evaluations of the 13-valent pneumococcal conjugate vaccine (PCV13) have been increasing over the last decade. No systematic reviews have synthesized the evidence of economic evaluations of the PCV13.

AREAS COVERED

We systematically searched the literature which published on peer-reviewed journals from January 2010 to June 2022. The literature search was conducted in the following electronic databases: PubMed, Web of Science, Embase, the Cochrane Library, CNKI, Wanfang database, VIP database. We identified 1827 records from the database search. After excluding 511 duplicates, 1314 records were screened, of which 156 records were retained for the full-text reviews. A total of 44 studies were included in the review. Among the included studies, 33 studies were economic evaluations of PCV13 among children, and 11 studies were conducted among adults. The literature search initiated in April, 2022, and updated in June 2022.

EXPERT OPINION

Vaccination with PCV13 was found to significantly reduce the mortality and morbidity of pneumococcal diseases and was cost-effective compared to no vaccine or several other pneumococcal vaccines (e.g. PCV10, PPV23). Future research is advised to expand economic evaluations of PCV13 combined with dynamic model to enhance methodologic rigor and prediction accuracy.

Cost-utility of 20-valent pneumococcal conjugate vaccine compared to no vaccination and recommended alternative vaccines among Belgian adults

BACKGROUND

The Belgian Superior Health Council (SHC) preferentially recommended the 20-valent pneumococcal conjugate vaccine (PCV20) for adults aged ≥65 years, immunocompromised patients, and patients aged ≥50 years suffering from conditions that increase their risk for pneumococcal infections. The objective of this paper is to present the cost-utility of PCV20 compared to no vaccination and the alternative sequence of PCV15 followed by the 23-valent pneumococcal polysaccharide vaccine (PPV23) in this population.

RESEARCH DESIGN AND METHODS

The analysis employed a static Markov model capturing lifetime risk of pneumococcal infections, associated disutility, mortality, and costs from different healthcare payer perspectives.

RESULTS

Results indicated use of PCV20 among Belgian older and at-risk adults is highly cost-effective compared to no vaccination, with an incremental cost per quality-adjusted life-year (QALY) of €4,164. Compared to the sequential regimen (PCV15+PPV23), PCV20 vaccination is a cost-saving strategy. Subgroup analysis indicated PCV20 vaccination of at-risk adults aged 65-84 years would also be cost-saving from the national healthcare perspective.

CONCLUSION

Based on current knowledge, this analysis suggests that access to PCV20 should be proposed in all adults recommended for vaccination by the SHC as PCV20 prevents additional hospitalizations and deaths caused by pneumococcal infection at an affordable cost.

Review on Pneumococcal Infection in Children

Childhood pneumococcal infection is a growing concern among paediatricians especially, in countries where there is no routine vaccination program against Streptococcal pneumoniae. The disease is associated with significant morbidity and mortality in young children particularly those who are under the age of two years. Its main virulent factors include polysaccharide capsule, autolysin, pneumolysin, choline-binding Protein A, the higher chance for genetic transformation, and the presence of pilli that facilitate enhanced binding of bacteria to host cellular surfaces. More severe and invasive pneumococcal infections are seen in children with immunodeficiencies, hypofunctional spleen, malnutrition, chronic lung disease and nephrotic syndrome. The disease spectrum includes a range of manifestations from trivial upper respiratory tract infections to severe invasive pneumococcal disease (PD). The basis of diagnosis is the isolation of bacteria in the culture of body fluids including blood. Antibiotics are best guided by sensitivity patterns and the emergence of resistance is a growing concern.

The incremental burden of invasive pneumococcal disease associated with a decline in childhood vaccination using a dynamic transmission model in Japan: A secondary impact of COVID-19

The coronavirus disease 2019 (COVID-19) pandemic has disrupted childhood vaccinations, including pneumococcal conjugate vaccine (PCV). Evaluating the possible impact on the invasive pneumococcal disease (IPD) incidence associated with a decline in childhood pneumococcal vaccination is important to advocate the PCV programs. Using a deterministic, dynamic transmission model, the differential incidence and burden of IPD in children younger than 5 years in Japan were estimated between the rapid vaccination recovery (January 2021) and the delayed vaccination recovery (April 2022) scenarios for the next 10 years. In our model, the IPD incidence was reduced from 11.9/100,000 in 2019 to 6.3/100,000 in 2020, caused by a reduced transmission rate due to the COVID-19 mitigation measures. Assuming a recovery in the transmission rate in 2022 April, the incidence of IPD was estimated to increase with maximal incidence of 12.1 and 13.1/100,000 children under 5 years in the rapid and the delayed vaccination recovery scenarios. The difference in the total IPD incidence between these two scenarios was primarily driven by vaccine serotypes IPD incidence. The difference of incidence was not observed between the two scenarios after 2025. The persistent decline in childhood pneumococcal vaccination rates due to the impact of COVID-19 might lead to an increased IPD incidence and an incremental disease burden.

Cost-effectiveness of pneumococcal vaccination for elderly in Sweden

INTRODUCTION

The aim was to assess cost-effectiveness of including pneumococcal vaccination for elderly in a national vaccination programme in Sweden, comparing health-effects and costs of pneumococcal related diseases with a vaccination programme versus no vaccination.

METHOD

We used a single-cohort deterministic decision-tree model to simulate the current burden of pneumococcal disease in Sweden. The model accounted for invasive pneumococcal disease (IPD) and pneumonia caused by pneumococci. Costs included in the analysis were those incurred when treating pneumococcal disease, and acquisition and administration of the vaccine. Health effects were measured as quality-adjusted life years (QALY). The time-horizon was set to five years, both effects and costs were discounted by 3% annually. Health-effects and costs were accumulated over the time-horizon and used to create an incremental cost-effectiveness ratio. The 23-valent polysaccharide vaccine (PPV23) was used in the base-case analysis. The 13-valent pneumococcal conjugate vaccine PCV13 was included in sensitivity analyses.

RESULTS

A vaccination programme using PPV23 would reduce the burden of pneumococcal related disease significantly, both when vaccinating a 65-year-old cohort and a 75-year-old cohort. IPD would decrease by 30% in the 65-year-old cohort, and by 29% in the 75-year-old cohort. The corresponding figures for CAP (communicable acquired pneumonia) are 19% and 15%. The cost per gained QALY was estimated to EUR 94,000 for vaccinating 65-year-olds and EUR 29,500 for 75-year-olds. With one dose PCV13 given instead of PPV23, the cost per gained QALY would increase by around 400% for both cohorts. The results were robust in sensitivity analyses.

CONCLUSION

Introducing a vaccination programme against pneumococcal disease for 65-year-olds in Sweden is unlikely to be cost-effective, whereas it for 75 year-olds and using PPV23 can be considered good value for money. Our model indicates that vaccine price needs to be reduced by 55% for vaccination of 65-year-olds to be cost-effective, given a threshold of EUR 50,000.