Longitudinal study of intravenous versus subcutaneous immunoglobulin replacement therapy in hematological malignancy.

AIM: To present findings from a longitudinal study on infection risk, mortality, and patient perspective of intravenous immunoglobulin (IVIg) and subcutaneous immunoglobulin (SCIg) treatment for patients with hypogammaglobulinemia secondary to hematological malignancy or its treatment (abbreviated as SID). METHODS: Observational study period included final year of IVIg (13 patients) and of the first 3 years of SCIg (17 patients) with SID. Data were collected on clinical outcomes from medical records and patient perception via study specific questionnaire. RESULTS: The median age was 63 years (53-76 years), and for 82.4% of patients their hematological malignancy was in complete remission. The annual mean serum IgG trough levels remained stable over the 4 years and were 7.0 g/L (±2.77 g/L) with IVIg, and 8.0 g/L (±1.75 g/L), 8.7 g/L (±2.75 g/L), and 7.6 g/L (±2.89 g/L) (year 1, 2, and 3, respectively) with SCIg. While the annual infection rate was similar, the rate of hospitalization due to infection fluctuated, with 37%, 9%, 15%, and 32% in year 1, 2, 3, and 4 respectively. There were no systemic adverse events with IVIg or SCIg. Patients reported a strong preference for SCIg. One patient died due to progression of underlying disease and infection within the study period. CONCLUSION: SCIg was the preferred treatment mode over IVIg in our cohort, but both were well tolerated without any systemic adverse events in 4-year follow up. The dosage and serum IgG levels were stable throughout. However, the number of infections requiring hospitalization fluctuated. It is anticipated that these findings encourage more hospitals to offer SCIg for SID patients.

Primary immunodeficiency disease: a cost-utility analysis comparing intravenous vs subcutaneous immunoglobulin replacement therapy in Australia.

BACKGROUND: Hospital-based intravenous immunoglobulin (IVIg) treatment has been the standard treatment mode for patients with primary immunodeficiency disease (PID). With the newer home-based subcutaneous immunoglobulin (SCIg) becoming approved for use in most countries, the question arises as to whether SCIg is a cost-effective treatment mode compared to IVIg in Australia. MATERIALS AND METHODS: We developed a Markov cohort simulation model with six health states: PID without infection, PID with infection treated at home or hospital, bronchiectasis without infection, bronchiectasis with infection treated at home or hospital, bronchiectasis with chronic Pseudomonas aeruginosa infection, and death, from an Australian healthcare system perspective. A 10-year time horizon with weekly cycles was chosen, and the expected costs and quality-adjusted life-years (QALYs) of the two treatment options estimated. RESULTS: The cumulative 10-year cost per patient was 297,547 Australian dollars (A$) with IVIg and A$ 251,713 for SCIg. IVIg resulted in 5.55 QALYs and SCIg 5.57 QALYs. Thus, SCIg appears to be a cost-saving option and possibly improves QALY from the Australian healthcare system perspective (i.e., the dominant treatment option). A probabilistic sensitivity analysis showed that the SCIg option is preferred in 93.2% of simulations given willingness to pay of A$ 50,000 per QALY gained. DISCUSSION: The results suggest that home-based SCIg is a cost-effective treatment option for patients with PID in Queensland, Australia.

Cost-utility analysis comparing hospital-based intravenous immunoglobulin with home-based subcutaneous immunoglobulin in patients with secondary immunodeficiency.

BACKGROUND AND OBJECTIVE: Immunoglobulin replacement therapy (IRT) is often used to support patients with primary immunodeficiency disease (PID) and secondary immunodeficiency disease (SID). Home-based subcutaneous immunoglobulin (SCIg) is reported to be a cheaper and more efficient option compared to hospital-based intravenous immunoglobulin (IVIg) for PID. In contrast, there is little information on the cost-effectiveness of IRT in SID. However, patients who develop hypogammaglobulinaemia secondary to other conditions (SID) have different clinical aetiology compared to PID. This study assesses whether SCIg provides a good value-for-money treatment option in patients with secondary immunodeficiency disease (SID). METHODS: A Markov cohort simulation model with six health states was used to compare cost-effectiveness of IVIg with SCIg from a healthcare system perspective. The costs of treatment, infection and quality-adjusted life years (QALYs) for IVIg and SCIg treatment options were modelled with a time horizon of 10 years and weekly cycles. Deterministic and probabilistic sensitivity analyses were performed around key parameters. RESULTS: The cumulative cost for IVIg was A$151 511 and for SCIg A$144 296. The QALYs with IVIg were 3·07 and with SCIg 3·51. Based on the means, SCIg is the dominant strategy with better outcomes and at lower cost. The probabilistic sensitivity analysis shows that 88·3% of the 50 000 iterations fall below the nominated willingness to pay threshold of A$50 000 per QALY. Therefore, SCIg is a cost-effective treatment option. CONCLUSION: For SID patients in Queensland (Australia), the home-based SCIg treatment option provides better health outcomes and cost savings.

Subcutaneous Immunoglobulin Therapy for Hypogammaglobulinemia Secondary to Malignancy or Related Drug Therapy.

Immunoglobulin replacement therapy (IRT) has an important role in minimizing infections and improving the health-related quality of life (HRQoL) in patients with immunodeficiency, who would otherwise experience recurrent infections. These plasma-derived products are available as intravenous immunoglobulin (IVIg) or subcutaneous immunoglobulin (SCIg). The global demand for these products is growing rapidly and has placed pressure on supply. Some malignancies and their treatment (as well as other medical therapies) can lead to secondary hypogammaglobulinemia or secondary immunodeficiency (SID) requiring IRT. Although IVIg use in this cohort has well-established therapeutic benefits, little is known about SCIg use. A literature search in July 2015 found only 7 published articles on SCIg use. These articles found that both IRT modes had equivalent efficacy in regard to reduction of bacterial infections. In addition, SCIg was reported to produce higher serum IgG trough levels compared with IVIg on equivalent dosage with the added benefit of fewer adverse effects. Patient HRQoL reports demonstrate preference for SCIg because of reduced adverse effects and hospital visits. There are no health economic models published on SCIg use in SID, but models on primary immunodeficiency disease and IRT conclude that SCIg provided greater economic benefits than IVIg. The findings of this small number of reports suggest that SCIg therapy for patients with SID is likely to be beneficial for both the patient and health care providers. To substantiate wider use of SCIg in SID, larger and more detailed studies are needed to accurately quantify the effectiveness of SCIg.