Evaluation of the dosing strategies of biologic agents and the theoretical impact of dose rounding.

Introduction Monoclonal antibodies possess unique pharmacokinetic properties that permit flexible dosing. Increased use and high costs of these medications have led to the development of cost-containing strategies. This study aims to quantify the cost savings and clinical impact associated with dose rounding monoclonal antibodies to the nearest vial size. Methods This study was a single-arm, retrospective chart review assessing all monoclonal antibody doses dispensed at an outpatient community infusion center associated with an academic medical center between August 2014 and August 2015. All monoclonal antibody doses were reviewed to determine the cost of drug wasted using two methods. The waste-cost analysis described the amount of drug disposed of due to the use of partial vials. The theoretical dose savings described potential cost avoidance based on rounding the ordered dose to the nearest vial size. The theoretical rounded dose was compared to the actual ordered dose to explore clinical implications. Results A total of 436 doses were included. Of these, 237 were not rounded to the nearest vial size and included in the analysis. The cost of waste associated with these doses was $108,013.64 using actual wholesale price. The potential cost avoidance associated with the theoretical dose calculation was $83,595.53. Rounding these doses to the nearest vial size resulted in a median 6.7% (range, 1.4-20%) deviation from ordered dose. Conclusions Rounding monoclonal antibodies to the nearest vial size could lead to significant cost and waste savings with minimal deviation from the actual ordered dose.