A study presented at the 2018 American Society of Hematology Annual Meeting found that the use of an intravenous (IV) rituximab biosimilar resulted in cost savings compared to subcutaneous reference rituximab in a patient with non-Hodgkin lymphoma (NHL).
The researchers conducted a time-and-cost simulation analysis for one patient with NHL over the course of six treatment cycles with R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone) using either standard or rapid-infusion rituximab. The rituximab component of R-CHOP consists of an IV initiation in cycle one followed by IV standard infusion or 90-minute rapid-infusion, or subcutaneous administration in subsequent cycles.
The investigators used Q1 2018 average sales prices and 2018 reimbursement rates as listed in the Current Procedural Terminology code set to develop costs of the subcutaneous and the IV reference rituximab products. Costs for the biosimilar were estimated at 15% to 35% discounts from reference rituximab. Patients were classified by body size: small (1.6 m2), average (1.85 m2), and large (21.2 m2).
Following the first cycle of IV reference rituximab, switching to the subcutaneous formulation saved 650, 720, and 791 minutes for patients with small, average, and large body sizes, respectively, over the next five cycles compared to continued IV use.
Assuming a switch from the IV reference rituximab to the subcutaneous formulation at cycle two, the cost for six cycles of R-CHOP was $54 higher than rapid-infusion but $104 lower than the standard infusion of the IV reference for patients with small body size. For patients with medium body size, the cost of subcutaneous administration was lower than the cost of rapid and standard IV administration ($3,854 and $4,012, respectively). For patients with large body size, the subcutaneous product saved $7,762 and $7,920 versus the two IV infusions.
Compared to an IV biosimilar rituximab, the subcutaneous option was more expensive. For patients with small body size, the subcutaneous formulation cost $3,647 to $8,649 more versus standard infusion and $3,805 to $8,807 more versus rapid infusion of the biosimilar. For patients with medium body size, these ranges were $325 to $6,109 and $484 to $6,267 for the two infusions. For patients with large body size, at a biosimilar discount of 25% or greater, subcutaneous administration cost at least $286 more at a standard infusion rate. At a discount of at least 24%, subcutaneous administration cost at least $116 more than the rapid-infusion biosimilar rituximab.