Economic evaluation: immunoglobulin vs prophylactic antibiotics in hypogammaglobulinemia and hematological malignancies.

Patients with hematological malignancies are at high risk of developing hypogammaglobulinemia (HGG) and infections. Immunoglobulin (Ig) is one recommended option to prevent these infections, but it is expensive and its cost-effectiveness compared with other prevention strategies remains unknown. We conducted a trial-based economic evaluation from the Australian healthcare system perspective to estimate the 12-month cost-effectiveness of prophylactic Ig versus prophylactic antibiotics in 63 adults with HGG and hematological malignancies participating in the RATIONAL feasibility trial. Two analyses were conducted: 1) Cost-utility analysis (CUA) to assess the incremental cost per quality-adjusted life-year (QALY) gained; 2) Cost-effectiveness analysis (CEA) to assess the incremental cost per serious infection prevented (grade greater or equal to 3) and per any infection (any grade) prevented. Over 12 months, the total cost per patient was significantly higher in the Ig group than in the antibiotic group (mean difference AU$29,140, p<0.001). Most patients received intravenous Ig (IVIg), which was the main cost driver, only two patients in the intervention arm received subcutaneous Ig (SCIg). There were non-significant differences in health outcomes. Results showed Ig was more costly than antibiotics and associated with fewer QALYs. The incremental cost-effectiveness ratio (ICER) of Ig versus antibiotics was AU$111,262 per serious infection prevented, but Ig was more costly and associated with more infections when all infections were included. On average and for this patient population, Ig prophylaxis may not be cost-effective compared to prophylactic antibiotics. Further research is needed to confirm these findings in a larger population and considering longer-term outcomes. The trial was registered on the Australian and New Zealand Clinical Trials Registry (ACTRN12616001723471).