Intravenous immune globulin (IVIG) dosing optimization through use of alternative dosing weights can translate to an average cost reduction up to $3.89 million, according to a new study published in The American Journal of Health-System Pharmacy.

IVIG, a high-cost medication used in a diverse range of settings and at many institutions, is dosed using total body weight (TBW). Recent evidence suggests that alternative dosing weights reduce waste without compromising clinical outcomes, according to the current study. The authors sought to quantify the waste reduction potentially generated through the use of alternative IVIG dosing weights.

In their retrospective analysis, the researchers analyzed all IVIG doses administered from January 2011 to 2016 to adults at or above the age of 18 years. TBW and height at the age of administration were used to calculate prescribed dose (g/kg), ideal body weight (IBW), and adjusted body weight (AdjBW).

The researchers analyzed 3 dosing methods: the use of AdjBW if TBW is >120% IBW; AdjBW for all doses; and IBW for all doses. Outcomes included potential IVIG use averted, direct drug cost savings, and reductions in outpatient infusion times for each method.

A total of 9918 doses were administered to 2564 patients over 5 years, representing an average usage of 75,994 g/year, according to the study. If dosing methods 1, 2, and 3 had been used, the annual use of IVIG would have decreased by 21.9% (16,658 g/year, p < 0.001), 24.2% (18,371 g/year, p < 0.001), and 35.9% (27,252 g/year, p < 0.001), respectively.

According to the study, these data translate into average annual cost differences of $2.37 million, $2.62 million, and $3.89 million and average annual outpatient infusion time savings of 841 hours, 920 hours, and 1366 hours, respectively.

The researchers concluded from the results that IVIG dosing optimization through the use of alternative dosing weights represent a significant source of waste reduction and cost reduction.


REFERENCE

Figgins B, Aitken S, Whited L, et al. Optimization of intravenous immune globulin use at a comprehensive cancer center. Published October 17, 2019. American Journal of Health-System Pharmacy. https://doi.org/10.1093/ajhp/zxz233. Accessed November 4, 2019.