Modelling the Public Health Impact of MenACWY and MenC Adolescent Vaccination Strategies in Germany

INTRODUCTION

Invasive meningococcal disease (IMD) causes significant mortality and long-term sequelae. This study assesses the potential public health impact of adolescent vaccination strategies employing MenACWY and MenC vaccines in Germany, where the existing meningococcal immunisation programme predominantly involves MenC administration in toddlers.

METHODS

A dynamic transmission model was developed to simulate the carriage of five meningococcal serogroup compartments (AY/B/C/W/Other) from 2019 until 2060 within 1-year age groups from 0 to 99 years of age. IMD cases were estimated based on case-carrier ratios. The model considered vaccine effectiveness against carriage acquisition and IMD.

RESULTS

The model predicts that introducing MenACWY adolescent vaccination could lead to a considerable reduction in IMD incidence, with the potential to prevent up to 65 cases per year and a cumulative total of 1467 cases by 2060. This decrease, mainly driven by herd effects, would result in a reduction of IMD incidence across all age groups, regardless of vaccination age. Furthermore, implementing MenACWY vaccination in adolescents is projected to decrease annual MenACWY-related IMD mortality by up to 64%, equating to an overall prevention of 156 IMD deaths by 2060. These protective outcomes are expected to culminate in approximately 2250 life years gained (LYG) throughout the model's projected time horizon. In contrast, the adoption of MenC vaccination in adolescents is predicted to have minimal influence on both IMD incidence and mortality, as well as on LYG.

CONCLUSION

The results of this study demonstrate that implementing MenACWY vaccination for adolescents in Germany is likely to notably reduce IMD incidence and mortality across age groups. However, the introduction of MenC adolescent vaccination shows only limited impact. Considering the extensive healthcare resources typically required for IMD management, these findings suggest the potential for economic benefits associated with the adoption of MenACWY adolescent vaccination, warranting further cost-effectiveness analysis.

Functional studies with IgM and IgA immunoglobulins: binding to pIgR, FcαμR, FcμR, and CDC activities

IgMs are the first antibodies produced by the immune system upon encounter of a possible pathogen and are one of five antibody subclasses in humans. For IgG, the most intensively studied antibody class, the N-linked glycosylation site located in the Fc-domain is directly involved in high affinity binding to the respective receptors and initiation of corresponding immune response. IgM molecules have five N-glycosylation sites and one N-glycosylation site in the J-chain, which can be incorporated in IgM or IgA molecules. There is only limited knowledge available concerning the function of these N-glycosylations in IgMs. To address this question, we produced IgM molecules lacking a particular N-glycosylation site and tested these variants as well as IgA molecules for binding to the known receptors: the polymeric immunoglobulin receptor (pIgR), the dual receptor for IgA and IgM, FcαμR, and the specific receptor for IgM, FcμR. The single glycosylation sites did not show an impact on expression and multimerization, except for variant N402Q, which could not be expressed. In SPR measurements, no major impact on the binding to the receptors by particular glycosylation sites could be detected. In cellular assays, deglycosylated variants showed some alterations in induction of CDC activity. Most strikingly, we observed also binding of IgA to the FcμR in the same affinity range as IgM, suggesting that this might have a physiological role. To further substantiate the binding of IgA to FcμR we used IgA from different origins and were able to confirm binding of IgA preparations to the FcμR.

Glycated haemoglobin, HOMA2-B, C-peptide to glucose ratio and type 2 diabetes clusters as predictors for therapy failure in individuals with type 2 diabetes without insulin therapy: A registry analysis

AIM

Some people with type 2 diabetes mellitus (T2D) and declining β-cell function do require insulin over time. Various laboratory parameters, indices of glucose metabolism or phenotypes of T2D (clusters) have been suggested, which might predict future therapy failure (TF), indicating the need for insulin therapy initiation. This analysis evaluated glycated haemoglobin (HbA1c), homeostatic model assessment (HOMA)2-B, C-peptide to glucose ratio (CGR) and diabetes clusters as predictive parameters for the occurrence of glycaemic TF in individuals diagnosed with T2D without previous insulin therapy.

MATERIALS AND METHODS

In total, 159 individuals with T2D [41% female, median age 50 (IQR: 53-69) years, diabetes duration 9 (5-15) years], without insulin therapy were prospectively evaluated for the occurrence of a composite primary endpoint, including HbA1c increasing or remaining >8.0% (64 mmol/mol) 3 months after baseline on non-insulin glucose-lowering agents, insulin initiation or hospital admissions because of acute hyperglycaemic events. Diabetes clusters were formed according to previously described characteristics. Only severe autoimmune diabetes clusters were excluded because of a small amount of glutamate decarboxylase antibody-positive participants. The other clusters were distributed as mild age-related diabetes 33%; severe insulin-deficient diabetes 31%; mild obesity-related diabetes 20%; and severe insulin-resistant diabetes 15%.

RESULTS

During a median observation of 57 months, higher tertiles of HbA1c at baseline, HOMA2-B, as well as a lower CGR were significantly predictive for the occurrence of the primary endpoint. The probability of meeting the primary endpoint was the highest for mild obesity-related diabetes [hazard ratio 3.28 (95% confidence interval 1.75-6.2)], followed by severe insulin-deficient diabetes [hazard ratio 2.03 (95% confidence interval 1.1-3.7)], mild age-related diabetes and the lowest for severe insulin-resistant diabetes. The best performance to predict TF with an area under the curve (AUC) of 0.77 was HbA1c at baseline, followed by HOMA2-B (AUC 0.69) and CGR (AUC 0.64).

CONCLUSION

HbA1c, indices of insulin secretion capacity (HOMA2-B and CGR) and T2D clusters might be applicable tools to guide practitioners in the decision of whether insulin is required in people already diagnosed with T2D. These findings need to be validated in prospective studies.

Polysialic acid promotes remyelination in cerebellar slice cultures by Siglec-E-dependent modulation of microglia polarization

Multiple sclerosis is an inflammatory demyelinating disease of the central nervous system. Spontaneous restoration of myelin after demyelination occurs, but its efficiency declines during disease progression. Efficient myelin repair requires fine-tuning inflammatory responses by brain-resident microglia and infiltrating macrophages. Accordingly, promising therapeutic strategies aim at controlling inflammation to promote remyelination. Polysialic acid (polySia) is a polymeric glycan with variable chain lengths, presented as a posttranslational modification on select protein carriers. PolySia emerges as a negative regulator of inflammatory microglia and macrophage activation and has been detected on oligodendrocyte precursors and reactive astrocytes in multiple sclerosis lesions. As shown recently, polySia-modified proteins can also be released by activated microglia, and the intrinsically released protein-bound and exogenously applied free polySia were equally able to attenuate proinflammatory microglia activation via the inhibitory immune receptor Siglec-E. In this study, we explore polySia as a candidate substance for promoting myelin regeneration by immunomodulation. Lysophosphatidylcholine-induced demyelination of organotypic cerebellar slice cultures was used as an experimental model to analyze the impact of polySia with different degrees of polymerization (DP) on remyelination and inflammation. In lysophosphatidylcholine-treated cerebellar slice cultures, polySia-positive cells were abundant during demyelination but largely reduced during remyelination. Based on the determination of DP24 as the minimal polySia chain length required for the inhibition of inflammatory BV2 microglia activation, pools with short and long polySia chains (DP8-14 and DP24-30) were generated and applied to slice cultures during remyelination. Unlike DP8-14, treatment with DP24-30 significantly improved remyelination, increased arginase-1-positive microglia ratios, and reduced the production of nitric oxide in wildtype, but not in Siglec-E-deficient slice cultures. In vitro differentiation of oligodendrocytes was not affected by DP24-30. Collectively, these results suggest a beneficial effect of exogenously applied polySia DP24-30 on remyelination by Siglec-E-dependent microglia regulation.

An artificial intelligence-based approach for identifying rare disease patients using retrospective electronic health records applied for Pompe disease

Objective

We retrospectively screened 350,116 electronic health records (EHRs) to identify suspected patients for Pompe disease. Using these suspected patients, we then describe their phenotypical characteristics and estimate the prevalence in the respective population covered by the EHRs.

Methods

We applied Symptoma's Artificial Intelligence-based approach for identifying rare disease patients to retrospective anonymized EHRs provided by the "University Hospital Salzburg" clinic group. Within 1 month, the AI screened 350,116 EHRs reaching back 15 years from five hospitals, and 104 patients were flagged as probable for Pompe disease. Flagged patients were manually reviewed and assessed by generalist and specialist physicians for their likelihood for Pompe disease, from which the performance of the algorithms was evaluated.

Results

Of the 104 patients flagged by the algorithms, generalist physicians found five "diagnosed," 10 "suspected," and seven patients with "reduced suspicion." After feedback from Pompe disease specialist physicians, 19 patients remained clinically plausible for Pompe disease, resulting in a specificity of 18.27% for the AI. Estimating from the remaining plausible patients, the prevalence of Pompe disease for the greater Salzburg region [incl. Bavaria (Germany), Styria (Austria), and Upper Austria (Austria)] was one in every 18,427 people. Phenotypes for patient cohorts with an approximated onset of symptoms above or below 1 year of age were established, which correspond to infantile-onset Pompe disease (IOPD) and late-onset Pompe disease (LOPD), respectively.

Conclusion

Our study shows the feasibility of Symptoma's AI-based approach for identifying rare disease patients using retrospective EHRs. Via the algorithm's screening of an entire EHR population, a physician had only to manually review 5.47 patients on average to find one suspected candidate. This efficiency is crucial as Pompe disease, while rare, is a progressively debilitating but treatable neuromuscular disease. As such, we demonstrated both the efficiency of the approach and the potential of a scalable solution to the systematic identification of rare disease patients. Thus, similar implementation of this methodology should be encouraged to improve care for all rare disease patients.

Intensified lipid-lowering treatment with alirocumab in patients with coronary heart disease

BACKGROUND

Atherosclerotic cardiovascular disease is the leading cause of death and disability in the Western world.

OBJECTIVE

To characterise adults with confirmed coronary heart disease (CHD) and primary heterozygous familial or non-familial hypercholesterolaemia or mixed dyslipidaemia who received alirocumab in a real-world setting.

METHODS

This open, prospective, multicentre, non-interventional study, conducted in Germany, enroled patients with confirmed CHD who were treated with alirocumab according to its summary of product characteristics. Prescription was at the physician's discretion and independent of study participation. Patients were followed for 12 weeks after alirocumab initiation.

RESULTS

In total, 245 patients (mean age 62.2 years; 34.0% female) were documented at 90 sites. Overall, 47.7% had familial hypercholesterolaemia, 48.9% non-familial hypercholesterolaemia and 43.8% mixed dyslipidaemia; 74.6% had hypertension and 29.2% diabetes mellitus. The most common lipid-lowering therapy in the 12 months preceding alirocumab was a statin, often in combination with ezetimibe (73.5%). Statin contraindications were documented for 46.2% patients and statin intolerance for 63.8%. The mean low-density lipoprotein cholesterol (LDL-C)-level prior to alirocumab was 150.5±51.6 mg/dL. Alirocumab prescription was in compliance with German national recommendations and/or European guidelines. The most common starting dose was 75 mg every other week. Overall, 57% patients reached target LDL-C levels (<70 mg/dL) after 12 weeks of treatment. Alirocumab was generally well tolerated.

CONCLUSION

In a real-world setting in Germany, alirocumab was prescribed for patients with atherosclerotic cardiovascular disease who had high baseline LDL-C levels with or without statin intolerance. Efficacy and safety were consistent with findings observed in the ODYSSEY Phase III programme.