The impact of acute pneumococcal disease on health state utility values: a systematic review

Pediatric Pneumococcal Conjugate Vaccine and Dosing Schedule Perceptions Among Health Care Providers and Caregivers in Germany, France, Spain, and Greece

INTRODUCTION

Most European infant national immunization programs (NIPs) recommend pneumococcal conjugate vaccines (PCVs), which currently cover 10-15 serotypes administered in a three-dose schedule (two primary  plus one booster). Recently, a PCV covering 20 serotypes that is administered in a four-dose schedule (three primary plus one booster) was licensed.

METHODS

An online survey was administered to collect data from health care providers (HCPs) and caregivers of children aged 0-5 (including expectant mothers) in four European countries (Germany, France, Spain, and Greece). All caregiver respondents had a shared or full responsibility to make health decisions for their child. Data on opinions, perceptions, and openness to a change in childhood vaccination dosing schedules were collected, along with demographic information for HCPs as well as caregivers.

RESULTS

A total of 601 HCPs and 1954 caregivers were recruited across the four countries. Nearly all HCPs (93%) agreed that broader serotype coverage against pneumococcal disease for children is a significant unmet need, and 92% had a "sense of urgency" to vaccinate children. Both HCPs and caregivers were supportive of an additional PCV dose and doctor visit, assuming it provided at least 20% more serotype coverage than what is currently available. Caregivers strongly agreed on the importance of full vaccination for pneumococcal disease, even if an extra dose and visit to the doctor was required.

CONCLUSIONS

HCPs and caregivers were virtually unanimous in their support for a PCV with broader serotype coverage and showed a subsequent willingness to include an extra infant dose/visit. These results can help guide broader discussions regarding public health policy and vaccine administration in the context of important efforts to reduce the global disease burden associated with pneumococcal disease.

Cost-effectiveness analyses of 15- and 20-valent pneumococcal conjugate vaccines for Japanese elderly

BACKGROUND

Despite the 23-valent pneumococcal polysaccharide vaccine (PPSV23) vaccination programme implementation, pneumococcal disease (PD) remains an important cause of morbidity and mortality among the elderly in Japan, particularly since childhood pneumococcal conjugate vaccine (PCV) vaccination programme continues to alter the serotype PD distribution among the elderly. Recently, in the United States, PCV15/PCV20 were recommended for adults aged ≥ 65 years and those aged 19-64 years with certain underlying conditions. In Japan, PCV15 is under the approval application process and PCV20 undergoing clinical trials, which has warranted the need in evaluating their value for money.

METHODS

We conducted cost-effectiveness analyses with Markov model and calculated incremental cost-effectiveness ratios of PCV15/PCV20 vaccination programme compared to status quo from payers' perspective. Transition probabilities and utility weights in estimating quality-adjusted life-year (QALY), and disease treatment costs were either estimated or obtained from literature. To reflect the situation of COVID-19 pandemic, epidemiological data from 2020 and beyond were used.

RESULTS

Compared to the current vaccination programme, PCV20 vaccination programme gained more QALYs with less cost, while PCV15 vaccination programme cost ¥35,020 (US$318, US$1 = ¥110) to gain an additional QALY. Replacing PPSV23 vaccination programme with PCV20 vaccination programme is cost-saving. One-way sensitivity analyses revealed that lower VE limits of PCVs against non-bacteremic pneumonia (NBP) have large impact to change the result from PCV20 vaccination programme dominated PPSV23 vaccination programme to PPSV23 vaccination programme dominated PCV20 vaccination programme.

CONCLUSION

In the COVID-19 era, replacing current PPSV23 with a single-dose PCV15- or PCV20 immunisation programme for 65-year-old adults in Japan is highly cost-effective, while the PCV 20 vaccination programme was observed to be more favourable.

Pneumococcal Surface Protein A-Hybrid Nanoparticles Protect Mice from Lethal Challenge after Mucosal Immunization Targeting the Lungs

Pneumococcal disease remains a global burden, with current conjugated vaccines offering protection against the common serotype strains. However, there are over 100 serotype strains, and serotype replacement is now being observed, which reduces the effectiveness of the current vaccines. Pneumococcal surface protein A (PspA) has been investigated as a candidate for new serotype-independent pneumococcal vaccines, but requires adjuvants and/or delivery systems to improve protection. Polymeric nanoparticles (NPs) are biocompatible and, besides the antigen, can incorporate mucoadhesive and adjuvant substances such as chitosans, which improve antigen presentation at mucosal surfaces. This work aimed to define the optimal NP formulation to deliver PspA into the lungs and protect mice against lethal challenge. We prepared poly(glycerol-adipate-co-ω-pentadecalactone) (PGA-co-PDL) and poly(lactic-co-glycolic acid) (PLGA) NPs using an emulsion/solvent evaporation method, incorporating chitosan hydrochloride (HCl-CS) or carboxymethyl chitosan (CM-CS) as hybrid NPs with encapsulated or adsorbed PspA. We investigated the physicochemical properties of NPs, together with the PspA integrity and biological activity. Furthermore, their ability to activate dendritic cells in vitro was evaluated, followed by mucosal immunization targeting mouse lungs. PGA-co-PDL/HCl-CS (291 nm) or CM-CS (281 nm) NPs produced smaller sizes compared to PLGA/HCl-CS (310 nm) or CM-CS (299 nm) NPs. Moreover, NPs formulated with HCl-CS possessed a positive charge (PGA-co-PDL +17 mV, PLGA + 13 mV) compared to those formulated with CM-CS (PGA-co-PDL -20 mV, PLGA -40 mV). PspA released from NPs formulated with HCl-CS preserved the integrity and biological activity, but CM-CS affected PspA binding to lactoferrin and antibody recognition. PspA adsorbed in PGA-co-PDL/HCl-CS NPs stimulated CD80+ and CD86+ cells, but this was lower compared to when PspA was encapsulated in PLGA/HCl-CS NPs, which also stimulated CD40+ and MHC II (I-A/I-E)+ cells. Despite no differences in IgG being observed between immunized animals, PGA-co-PDL/HCl-CS/adsorbed-PspA protected 83% of mice after lethal pneumococcal challenge, while 100% of mice immunized with PLGA/HCl-CS/encapsulated-PspA were protected. Therefore, this formulation is a promising vaccine strategy, which has beneficial properties for mucosal immunization and could potentially provide serotype-independent protection.