Modeling Primary Immunodeficiency Disease Epidemiology and Its Treatment to Estimate Latent Therapeutic Demand for Immunoglobulin

Using a scenario approach to assess for the current and future demand of immunoglobulins: An interview and literature study from The Netherlands

OBJECTIVES

To explore the current and future demand of immunoglobulins globally and specifically for the Netherlands by assessing: (I) which specialties contribute to current demand, (II) new areas of medical need, (III) which transformational factors may impact demand and to what effect, by using a scenario approach.

BACKGROUND

As immunoglobulin demand continues to increase globally, there is concern of increasing shortages and questions of whether and how future demand will continue based on medical need.

METHODS/MATERIALS

In line with scenario principles, a scoping review of Pubmed, Web of Science, Embase and Cochrane and grey literature was conducted. Semi-structured interviews with subject matter experts were held. The results of the review and interviews were analysed for major themes.

RESULTS

The scoping review resulted in 97 articles, 74 regarding clinical uses, and 23 regarding organisational and other themes. Fifteen clinical and non-clinical experts were interviewed. I) Neurology, immunology, and haematology were specialties that contribute most to current demand. II) Regarding potential new areas of medical need, the literature review resulted in more indications than the interviews, for example, post-renal transplants. III) Four groups of key transformational factors were found: factors that could increase immunoglobulin demand (e.g., EMA revisions), decrease demand (e.g., replacement products, Dutch Transfer Act 2021), factors that remain to be seen how it impacts demand (e.g., further evidence), and miscellaneous factors (e.g., supply-related).

CONCLUSION

Having identified the specialties and relevant transformational factors that affect immunoglobulin demand, more research is needed on what clinical or organisational strategies would be effective in controlling demand in general for the Netherlands and abroad. Other blood establishments may also use a scenario approach to increase preparedness for future (un)expected developments.

Predictive Factors for and Complications of Bronchiectasis in Common Variable Immunodeficiency Disorders

Bronchiectasis is a frequent complication of common variable immunodeficiency disorders (CVID). In a cohort of patients with CVID, we sought to identify predictors of bronchiectasis. Secondly, we sought to describe the impact of bronchiectasis on lung function, infection risk, and quality of life. We conducted an observational cohort study of 110 patients with CVID and an available pulmonary computed tomography scan. The prevalence of bronchiectasis was 53%, with most of these patients (54%) having mild disease. Patients with bronchiectasis had lower median serum immunoglobulin (Ig) concentrations, especially long-term IgM (0 vs 0.25 g/l; p < 0.01) and pre-treatment IgG (1.3 vs 3.7 g/l; p < 0.01). CVID patients with bronchiectasis had worse forced expiratory volume in one second (2.10 vs 2.99 l; p < 0.01) and an annual decline in forced expiratory volume in one second of 25 ml/year (vs 8 ml/year in patients without bronchiectasis; p = 0.01). Patients with bronchiectasis also reported more annual respiratory tract infections (1.77 vs 1.25 infections/year, p = 0.04) and a poorer quality of life (26 vs 14 points in the St George's Respiratory Questionnaire; p = 0.02). Low serum immunoglobulin M concentration identifies patients at risk for bronchiectasis in CVID and may play a role in pathogenesis. Bronchiectasis is relevant because it is associated with frequent respiratory tract infections, poorer lung function, a greater rate of lung function decline, and a lower quality of life.

Estimation of the latent therapeutic demand for immunoglobulin therapies in autoimmune neuropathies in the United States

BACKGROUND AND OBJECTIVES

The use of immunoglobulin (IG) solutions as an immunomodulatory therapy in certain neurological conditions has become an established modality and represents a significant proportion of total IG use. The estimation of the evidence-based potential demand designated as the latent therapeutic demand (LTD) for IG in these diseases is required for adequate planning of the plasma supply required to manufacture the product.

MATERIALS AND METHODS

The diseases studied included chronic inflammatory demyelinating polyneuropathy (CIDP), Guillain-Barré syndrome (GBS) and multifocal motor neuropathy (MMN). The LTD for IG was assessed using a decision analysis model, using Microsoft Excel. The model analysed the epidemiological and clinical factors contributing to IG usage. One-way sensitivity analysis and probabilistic sensitivity analysis derived the LTD in grams per 1000 inhabitants. The key variables included the treatment schedule and the prevalence of the disease.

RESULTS

The model estimates that an average annual IG demand and standard deviation for CIDP, GBS and MMN in the United States is 83.05 ± 24.5, 6.1 ± 3.2 and 36.1 ± 25.5 g/1000 inhabitants, respectively.

CONCLUSION

Together with previous work on the LTD for IG in immunodeficiencies, these results indicate that current IG usage reflects the estimated LTD for the main indications for IG in the United States The wide range of LTD found in all these studies emphasizes the need for more precise assessment of the underlying variables, particularly disease prevalence and dosage. Further studies on other indications such as secondary immunodeficiencies will augment these results and will assist in guiding demand planning for IG use and plasma collection in the United States and inform blood policy in other countries.

The growing importance of achieving national self-sufficiency in immunoglobulin in Italy. The emergence of a national imperative

Since the inception of industrial plasma fractionation during the Second World War, a succession of protein therapies isolated from plasma have determined the volume of plasma requiring collection, and have also shaped the economics of the industry. These so-called plasma drivers have successively included albumin, coagulation Factor VIII (FVIII) and, for the past thirty years, intravenously (IV) and subcutaneously (SC) administered immunoglobulin (IG) solutions. The sale of IG underpins the profitability of the industry and has experienced continuous growth over the past decades, as the result of growing clinical demand. Modelling this demand using decision analysis indicates that supplying the evidence-based indications for IG therapies will generate a need for IG which exceeds the current plasma collection capacity of most countries. A notable exception to this situation is the United States (US) of America, whose population of compensated plasma donors generates two thirds of the global supply of plasma for fractionation. The US is also the leading consumer of IG, and its health care providers pay the highest price for the product globally. Shortages of IG occur whenever the demand for the product outstrips the supply. Current shortages, following other historical periods of shortage, threaten the well-being of patients dependant on these products and incur heavy costs on health systems. In Italy, the national blood system, which is based on voluntary unpaid donors, reflects a policy of national self-sufficiency in blood-derived therapies (a strategic objective of the national blood system itself), based on solidarity as an ethical principle. This system has increased the collection of plasma for fractionation by 3.8% per annum over 2008-2017, in accordance to a plan for plasma procurement targeting a collection rate of 14.1 L of plasma per thousand (10³) population by 2020. Over the same period, IG usage has increased by 8.5/per annum, to 89.2 g IG/10³ population. In this paper, we review the factors which, increasingly, are causing an imbalance between the global supply and demand for IG, and we assess Italy's capacity to ensure that increasing this level of independence is no longer simply an ethical, but also an economic imperative, with implications for the security of Italy's health system.

Direct and Indirect Costs of Immunoglobulin Replacement Therapy in Patients with Common Variable Immunodeficiency (CVID) and X-Linked Agammaglobulinemia (XLA) in Italy

BACKGROUND

In Italy, there is scarce evidence on the epidemiological and economic burden induced by primary antibody deficiencies.

OBJECTIVE

The aim of this study was to elaborate the available epidemiological and cost data in order to estimate the annual expenditure induced by the management of patients affected by the common variable immunodeficiency (CVID) and X-linked agammaglobulinemia (XLA) requiring immunoglobulin (Ig) replacement therapy.

METHODS

A probabilistic cost-of-illness model was developed to estimate the number of patients with CVID and XLA, and the economic burden associated with their therapy in terms of direct or indirect costs. A systematic literature review was carried out to reveal both epidemiological and economic data. Furthermore, a probabilistic sensitivity analysis with 5000 Monte Carlo simulations was performed.

RESULTS

The epidemiological model allowed us to estimate the number of prevalent patients affected by XLA and CVID in Italy in 2017, corresponding to 1885 (95% confidence interval [CI] 944-3145) and 133 (95% CI 115-152) patients, respectively. The estimated total expenditure for the treatment and management of patients with CVID and XLA requiring Ig replacement therapy amounts to €42.68 million (95% CI €14.38-€86.1 million).

CONCLUSIONS

This information provides a comprehensive perspective of the economic issues, and facilitates better-informed public health decision making, in the management of CVID and XLA in Italy.

Common Variable Immunodeficiency and Liver Involvement

Common variable immunodeficiency (CVID) is a primary B-cell immunodeficiency disorder, characterized by remarkable hypogammaglobulinemia. The disease can develop at any age without gender predominance. The prevalence of CVID varies widely worldwide. The underlying causes of CVID remain largely unknown; primary B-cell dysfunctions, defects in T cells and antigen-presenting cells are involved. Although some monogenetic defects have been identified in some CVID patients, it is likely that CVID is polygenic. Patients with CVID develop recurrent and chronic infections (e.g., bacterial infections of the respiratory or gastrointestinal tract), autoimmune diseases, lymphoproliferation, malignancies, and granulomatous lesions. Interestingly, autoimmunity can be the only clinical manifestation of CVID at the time of diagnosis and may even develop prior to hypogammaglobulinemia. The diagnosis of CVID is largely based on the criteria established by European Society for Immunodeficiencies and Pan-American Group for Immunodeficiency (ESID/PAGID) and with some recent modifications. The disease can affect multiple organs, including the liver. Clinical features of CVID patients with liver involvement include abnormal liver biochemistries, primarily elevation of alkaline phosphatase (ALP), nodular regenerative hyperplasia (NRH), or liver cirrhosis and its complications. Replacement therapy with immunoglobulin (Ig) and anti-infection therapy are the primary treatment regimen for CVID patients. No specific therapy for liver involvement of CVID is currently available, and liver transplantation is an option only in select cases. The prognosis of CVID varies widely. Further understanding in the etiology and pathophysiology will facilitate early diagnosis and treatments to improve prognosis.

Latent therapeutic demand model for the immunoglobulin replacement therapy of primary immune deficiency disorders in the USA

BACKGROUND AND OBJECTIVES

Our research aim is to model latent therapeutic demand (LTD) for the immunoglobulin replacement therapy (IgGRT) of primary immune deficiency disorders (PIDDs) in the USA. Given the high level of variability of IgGRT use and major differences among American and European practices in the management of patients with PIDDs, we develop a USA-specific LTD model for common variable immune deficiency (CVID), hyper IGM syndrome, severe combined immune deficiency, Wiskott-Aldrich syndrome and X-linked agammaglobulinemia (XLA).

METHODS AND MATERIALS

We use decision analysis methods to model the underlying IgGRT demand for PIDDs by assessing USA-specific epidemiology and treatment. Data for the epidemiology and treatment variables were obtained from the medical literature, USIDNET and Immune Deficiency Foundation. The uncertainty surrounding the variables was modelled using probability distributions and evaluated using Monte Carlo simulation.

RESULTS

The mean treatment dose from USIDNET and European Society for Immunodeficiencies (ESID) was significantly different for treating CVID, and the number of annual infusions from USIDNET and ESID was significantly different for treating CVID and XLA. The mean and standard deviation of LTD for all PIDDs is 105·1 ± 88·5 g per 1000 population, with CVID contributing the most to LTD.

CONCLUSION

Estimating country-specific LTD is important to ensure an adequate supply of IgGRT and an optimal treatment for patients with PIDDs and for improving national healthcare policymaking and production planning.

Errors and Omissions: Donor Compensation Policies and Richard Titmuss

Many global and national systems of regulation of blood donors and donor compensation rely for intellectual support on Richard Titmuss's views, represented in The Gift Relationship. Based on selective interpretation of data from the 1960s, Titmuss engineered an ethical view pertaining to donors and, in so doing, created not only ongoing stereotypes, but created a cause for followers to perpetuate misunderstandings about the nature of such donations. In many cases, donors are, in fact compensated, but regulatory systems persevere in using definitional fig leaves in order to perpetuate an ongoing political goal of diminishing private sector participation in health care. However, in more recent works, including new views of critical sociology and evolutionary psychology, the Titmuss worldview has been turned upside-down. Evidence readily available today proves the safety of compensated donation and the lives saved by encouraging policies for both compensated and non-compensated donation.

Primary immunodeficiencies in Chile evaluated through ICD-10 coded hospital admissions

BACKGROUND

The epidemiology and hospitalisation trends of primary immunodeficiency (PID) in Chile are unknown. We aimed to evaluate hospitalisation trends and demographic characteristics of PID admissions in Chile.

METHODS

PID admissions between 2001 and 2010 (ICD-10 codes D70.0, D70.4, D71, 72.0, D76.1, D80-D84, E70.3, G11.3) were reviewed using national hospital discharge databases.

RESULTS

During the study period, 5486 admissions due to PID were registered (0.03% of total). 58.5% of patients were male and 66.3% were under 18 years. Median length of stay was one day (range 1-403 days). The most frequent diagnoses were hypogammaglobulinaemia (27.6%), unspecified immunodeficiency (21.9%), haemophagocytic lymphohystiocytosis (18.3%) and common variable immunodeficiency (11.2%). There was a significant increase in PID admission rate and in one-day hospitalisations during this period (β=0.2; P=0.001 and β=33; P≤0.001, respectively), however no significant variation was found for longer admissions (β=4.8; P=0.175). The increasing trend in PID admission rate was significant in patients with private, but not public insurance (β=0.53; P≤0.001 vs. β=0.08; P=0.079, respectively).

CONCLUSIONS

We report an increasing trend in admissions due to PID in Chile over a 10-year period. Increase is mainly due to short hospitalisations, possibly accounting for improvements in IVIG access. Higher admission rates in patients with private vs. public insurance suggest socioeconomic disparities in access to PID treatment. ICD-10 coded hospitalisation databases may be useful to determine hospitalisation trends and demographic characteristics of PID admissions worldwide.

Como se estuda o que não se diz: uma revisão sobre demanda oculta

Objetivos: Pessoas com demandas aparentemente bem delimitadas podem, muitas vezes, ter queixas ou preocupações ocultas ou tardiamente apresentadas, chamadas em inglês de hidden agenda, by the way syndrome ou doorknob syndrome (“síndrome da maçaneta”). Poucos trabalhos abordam o fenômeno em contexto clínico discutindo seus aspectos ou consequências sobre o cuidado do ponto de vista sociocultural. Uma pesquisa qualitativa sobre saúde dos homens realizada pelos autores exigiu estudar a produção científica relacionada à hidden agenda de forma descritiva e interpretativa. Métodos: Esta revisão, do tipo estado da questão, abarcou artigos que tratassem da hidden agenda (ou expressões similares) no contexto clínico geral ou especializado, médico ou multiprofissional, em português, inglês ou espanhol, no período de 2000 a 2014. Partindo de 210 resultados iniciais em 3 bases de dados internacionais, foram selecionadas 39 publicações, que foram avaliadas quanto a características objetivas e subjetivas. Resultados: Identificando os temas predominantes nas pesquisas, notamos que hidden agenda é a expressão mais específica, sendo demanda oculta sua melhor tradução. Quase todos os estudos relacionavam a atenção a demandas ocultas a melhores desfechos ou desdobramentos do atendimento, embora nenhum avaliasse essas consequências de forma aprofundada. Conclusão: A revisão deixa claro que a demanda oculta é um elemento problematizador para pensar a prática médica e potencializador para a clínica, especialmente ao buscar-se um cuidado integral e um diálogo efetivo entre profissional e usuário(a). São necessários estudos que articulem o fenômeno a aspectos socioculturais ou tecnoassistenciais e que contemplem alguma discussão sobre construção da demanda, ausente nos artigos revisados.

Comprehensive activities to increase recognition of primary immunodeficiency and access to immunoglobulin replacement therapy in Poland

The study presents an overview on current situation of primary immunodeficiency (PID) patients in Poland and the 2014 annual report of the Polish Working Group for Immunodeficiency (PWGID). The group was set up in 2005 to improve diagnosis, treatment, and care of patients with immunodeficiencies and currently includes 15 pediatric and 13 adult centers. According to PWGID report 4099, PID patients are recognized in Poland, with the prevalence 10.6/100,000. The majority of them (54.2 %) have predominantly antibody deficiency (PAD). In 2014 alone, a total number of 731 newly diagnosed individuals are reported. As predicted, the vast majority (70 %) of them have PAD. Approximately one third of PAD patients require immunoglobulin replacement therapy. Within the entire cohort, an intravenous route of immunoglobulin therapy dominates (67.3 %). However, within the age groups, distribution of immunoglobulin therapy varies and seems to be age related. Among children, 36 % receive subcutaneous immunoglobulin, while with adults 26 %.

CONCLUSION

Analysis of numbers of either newly recognized or treated patients indicates its dynamic increase in recent years. This is the result of comprehensive activities by PWGID supported by governmental institutions, outstanding foundations, and patient's organization.

WHAT IS KNOWN

• Immunoglobulins' treatment has substantially changed the life of individuals with PAD. Patients with common variable immunodeficiency (CVID) or X-linked agammaglobulinemia (XLA) can live and lead a near normal life. Early diagnosis of the disease followed by earlier implementation of appropriate treatment, including gammaglobulin replacement therapy, improves the quality of life. • Targeted efforts of health care professionals and government are required to optimize diagnostic and therapeutic approach for PAD. What is New: • Comprehensive activities of PWGID lead to better recognition of PID individuals and should improve reporting Polish PIDs to the ESID database. • Following the joint efforts of immunologists, patient's, and governmental organizations in the end of 2014, the Therapeutic Program for Treatment Adults with PID was introduced, leading to universal access to currently available treatment options and to improve the quality of life.

Manufacture of immunoglobulin products for patients with primary antibody deficiencies - the effect of processing conditions on product safety and efficacy

Early preparations of immunoglobulin (Ig) manufactured from human plasma by ethanol (Cohn) fractionation were limited in their usefulness for substitution therapy in patients with primary antibody deficiencies (PAD), as Ig aggregates formed during manufacture resulted in severe systemic reactions in patients when given intravenously. Developments in manufacturing technology obviated this problem through the capacity to produce concentrated solutions of intact monomeric Ig, revolutionizing PAD treatment and improving patient life expectancy and quality of life. As the need for Ig has grown, manufacturers have refined further manufacturing technologies to improve yield from plasma and produce therapies, which are easier and less expensive to deliver. This has led to the substitution, partly or wholly, of ethanol precipitation by other techniques such as chromatography, and has also stimulated the production of highly concentrated solutions capable of rapid infusion. Ig products have been associated, since their inception, with certain adverse events, including infectious disease transmission, hemolysis, and thromboembolism. The introduction of standardized manufacturing processes and dedicated pathogen elimination steps has removed the risk of infectious disease, and the focus of attention has shifted to other problems, which appear to have increased over the past 5 years. These include hemolysis and thromboembolism, both the cause for substantial concern and the subject of recent regulatory scrutiny and actions. We review the development of manufacturing technology and the emerging evidence that changes for the optimization of yield and convenience has contributed to the recent incidents in certain adverse events. Industry measures under development will be discussed in terms of their potential to improve safety and optimize care for patients with PAD.

European consensus proposal for immunoglobulin therapies

The use of immunoglobulin (Ig) preparations (intravenous, IVIg, subcutaneous, SCIg) for replacement and immunomodulation therapy worldwide has tripled in the past 20 years and represents an ever-increasing cost factor for healthcare organizations. The limited access to the starting material of this essential medicinal product is currently the driving force for human plasma collection. Increasing awareness and improved diagnosis of human primary immunodeficiencies and a broadening of immunomodulatory indications are responsible for this development, and on a longer run might lead to plasma supply shortages. Consensus recommendations for the optimal use of Ig in clinical practice, including priority rankings for the most urgent indications, are therefore urgently needed. During a recent meeting in Kreuth, Germany, expert nominees from 36 Council of Europe states, together with colleagues from observer countries and regulatory agencies came up with this consensus statement.