Cost-effectiveness analysis of subcutaneous immunoglobulin replacement therapy in Iranian patients with primary immunodeficiencies

Ten-year population trends of immunoglobulin use, burden of adult antibody deficiency and feasibility of subcutaneous immunoglobulin (SCIg) replacement in Hong Kong Chinese

Background

Adult antibody deficiency remains under-recognised and under-studied - especially among Asian populations. Patterns of immunoglobulin use and the feasibility of subcutaneous immunoglobulin (SCIg) replacement among Chinese patients remains unclear.

Objective

To investigate the trends of immunoglobulin use, burden of adult antibody deficiency and the outcomes of patients on SCIg compared to intravenous immunoglobulin (IVIg) replacement in Hong Kong through a retrospective observational study.

Methods

Population-wide data of immunoglobulin recipients in Hong Kong between 2012 and 2021, and longitudinal clinical data of adult immunodeficiency patients at Queen Mary Hospital were collected and analysed.

Results

Total immunoglobulin consumption and recurrent immunoglobulin recipients increased continuously from 175,512g to 298,514g (ρ=0.99, p<0.001) and 886 to 1,508 (ρ=0.89, p=0.001) between 2012-21 in Hong Kong. Among 469 immunoglobulin recipients at Queen Mary Hospital in 2021, 344 (73.3%) were indicated for replacement. Compared to those on IVIg (n=14), patients on SCIg replacement (n=8) had fewer immunodeficiency-related hospitalisations (IRR=0.11) and shorter duration of hospitalisation stay (IRR=0.10) per year, as well as better quality of life (SF-36v2 Health Survey and Life Quality Index). Estimated annual healthcare cost of SCIg replacement per patient was lower than that of IVIg (HKD196,850 [USD25,096] vs HKD222,136 [USD28,319]).

Conclusion

There was a significantly increasing burden of adult antibody deficiency and immunoglobulin consumption in Hong Kong. SCIg was feasible and more cost-effective when compared to IVIg, with SCIg patients experiencing better clinical outcomes and quality of life. Future prospective studies to confirm the long-term efficacy and superiority of SCIg are required.

Trends in IVIG use at a tertiary care Canadian center and impact of provincial use mitigation strategies: 10-year retrospective study with interrupted time series analysis

BACKGROUND

Intravenous immunoglobulin (IVIG) is a fractionated plasma product used to treat a range of autoimmune or inflammatory conditions, as well as immunodeficiency. Demand for this high-cost product is increasing worldwide. Understanding historical changes in IVIG use is important for inventory management and demand forecasting as well as for the development of initiatives aimed at optimizing blood product use.

STUDY DESIGN AND METHODS

This was a 10-year retrospective cohort study of all patient encounters involving an IVIG transfusion from 2007 to 2016 at a four-site tertiary care hospital in Ontario, Canada. IVIG use was reported, including number of hospital encounters and amounts of IVIG prescribed. An interrupted time series analysis was performed to evaluate temporal changes in product use coinciding with the release of 2009-2010 provincial initiatives to optimize IVIG.

RESULTS

A total of 1,658,159.50 g of IVIG was administered from 2007 to 2016. Total annual volume administered initially decreased after implementation of new policies (-2032 g/quarter). The number of IVIG patient encounters also decreased (-49.8 encounters/quarter) but was mirrored by an increase in the total volume administered per patient encounter (+0.88 g/quarter). Use increased 820 g/quarter from 2013 to 2016 but was 21% lower than projected before implementation of provincial policies.

CONCLUSION

Trends in IVIG use show ongoing increases in the number of patients treated with the product. Development and implementation of provincial initiatives to optimize IVIG use coincided with significant short-term changes at a large tertiary care hospital. Novel initiatives aimed at dose minimization and prescription rationalization for this therapy are needed on local as well as larger scales.