Intravenous belimumab had benefits, but also resulted in more health care utilization due to the nature of its administration.
Patients with systemic lupus erythematosus (SLE) who initiate treatment with intravenous belimumab (Benlysta) experience a significant reduction in flare-ups and oral corticosteroid utilization. Yet, they also have higher health care utilization and costs, according to a new analysis.
The report found the average all-cause hospital costs for patients starting belimumab were $11,030 in the 12 months following therapy initiation, versus $7735 in the 12 months before starting the therapy. The study was published in the journal Clinical Therapeutics.
Corresponding author Christopher F. Bell, MSc, of GlaxoSmithKline, and colleagues, noted that patients with SLE often experience organ damage from disease activity, flares, and the long-term use of corticosteroids. This translates into frequent hospitalizations and thus high health care costs.
Belimumab is a recombinant human monoclonal antibody that works by selectively inhibiting B-cell activating factor, which correlates with disease activity in patients with SLE.
Intravenous administration of belimumab, which is marketed by GlaxoSmithKline, has been shown to reduce disease activity, flares, and the use of prednisone in patients with SLE. However, Bell and colleagues said its impact outside of clinical trials has not been thoroughly studied, nor has its impact on health care resource utilization.
In order to change that, the investigators consulted 2 claims databases, a commercial claims database and a Medicare database, looking for adult patients who received their first belimumab IV dose for SLE between 2012 and 2016.
A total of 908 patients were identified, most of whom (93.4%) were female. The patients had a mean Charlson Comorbidity Index score of 0.9, and 94.9% had moderate or severe disease.
Comparing patient claims from the year before treatment to the year after treatment, the authors found severe flare episodes dropped from 16.4% to 10.1% of patients. Moderate flares fell from 92.1% to 85.6%, and mild flares fell from 77.4% to 71.1%.
“Overall, there was a statistically significant reduction across all SLE flare severity categories in the proportion of patients experiencing an SLE flare episode from the 12-month pre-index period to the 12-month post-index period,” the authors wrote.
Meanwhile, the percentage of patients taking oral corticosteroids also fell. The proportion of patients taking a prednisone-equivalent dose of at least 60 mg/day went from 7.3% to 4.2%. The percentage of patients taking doses greater than 40 mg/day dropped from 14.1% to 7.9%.
Yet, there were no statistically significant differences in proportions of patients using all-cause health care services. Inpatient or emergency department hospital visits were similar, the authors said, though the administration of belimumab led to an average of 12.2 health care encounters (either outpatient visits or prescriptions).
Though the data showed a significant jump in mean all-cause hospital-based costs, the authors noted that their study revealed a similar phenomenon to what has been seen in the health care system as a whole; namely, that a small percentage of patients account for an outsize percentage of spending. Though the overall hospital costs increased on average, the costs for patients at the 75th, 90th, and 95th percentile actually decreased over the pre-index to post-index period.
The investigators noted several limitations, including the fact that their data was specific to intravenous belimumab, and thus would not be directly applicable to subcutaneous belimumab.
“Further studies will be useful to increase our understanding of SLE, with the specific goals of incorporating disease activity measures and long-term outcomes in future studies of [healthcare resource utilization], costs, and patient outcomes,” they concluded.
Lokhandwala T, Coutinho AD, Bell CF. Retrospective analysis of disease severity, health care resource utilization, and costs among patients initiating belimumab for the treatment of systemic lupus erythematosus. Clin Ther. Published online July 6, 2021. doi:10.1016/j.clinthera.2021.06.009