US Budget Impact of Rituximab-abbs vs Subcutaneous Rituximab for CLL and NHL

A budget impact model estimated that intravenous rituximab-abbs may yield significant annual cost savings compared to subcutaneous rituximab for patients with (non-Hodgkin lymphoma) NHL and chronic lymphocytic (CLL), according to a study presented at the virtual 2021 ASCO Annual Meeting.

“Rituximab-abbs is a CD20-directed monoclonal antibody and the first rituximab biosimilar approved in the US, expected to significantly reduce drug acquisition costs,” explained Elizabeth James, MD, Aventine Consulting, LLC, Marblehead, MA, and colleagues.

A budget impact model was created to identify incremental cost differences between intravenous rituximab-abbs and subcutaneous rituximab administrations over a period of one year for a hypothetical Medicare population comprising 5 million members. The budget impact model assumed equal efficacy and safety between both treatment options.

Scientific literature, product labels, and public resources were used to estimate costs for epidemiology, market share, drug dosing, and administration. The body surface area assumed for infused rituximab dosing was 1.8m2.

Annual dose counts of intravenous rituximab-abbs or subcutaneous rituximab per patient were: 10 untreated follicular lymphoma (FL) with maintenance; 8 untreated FL (without maintenance), relapsed/refractory FL, or untreated diffuse large B-cell lymphoma; 6 CLL. Intravenous rituximab-abbs infusion duration was 3 hours.

Drug acquisition and administration costs were derived from 2020 Average Sales Price pricing file and Centers for Medicare and Medicaid Services Physician Fee Schedule, and patient cost share was derived from 2020 Medicare Part B 20% cost-share for office visits and drugs. Further FL maintenance costs were estimated through a scenario analysis.

Among the 5-million member Medicare population, it was estimated that 972 patients would be treated with rituximab for NHL or CLL; 49 of whom would receive subcutaneous rituximab. Results from the budget impact model revealed that one-year incremental savings for a 13-patient shift from subcutaneous rituximab to rituximab-abbs were $57,864. Rituximab-abbs ranged between $2,359 and $8,186 in annual incremental savings per patient. 

“This budget impact model estimated annual savings of over $57,000 ($0.02 per enrolled member per year) for a 5-million-member US payer following a 25% shift of current subcutaneous rituximab use to rituximab-abbs,” concluded Dr James and colleagues, adding, “These findings demonstrate the potential economic benefits of rituximab-abbs vs subcutaneous rituximab that may result in expanded access to rituximab therapy.”—Marta Rybczynski