Real-world total cost of care by line of therapy in relapsed/refractory diffuse large B-cell lymphoma

There are multiple recently approved treatments and a lack of clear standard-of-care therapies for relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL). While total cost of care (TCC) by the number of lines of therapy (LoTs) has been evaluated, more recent cost estimates using real-world data are needed. This analysis assessed real-world TCC of R/R DLBCL therapies by LoT using the IQVIA PharMetrics Plus database (1 January 2015-31 December 2021), in US patients aged ≥18 years treated with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) or an R-CHOP-like regimen as first-line therapy.

Treatment costs and resources in the R/R setting were assessed by LoT. A sensitivity analysis identified any potential confounding of the results caused by the impact of the COVID-19 pandemic on healthcare utilization and costs. Overall, 310 patients receiving a second- or later-line treatment were included; baseline characteristics were similar across LoTs. Inpatient costs represented the highest percentage of total costs, followed by outpatient and pharmacy costs.

Mean TCC per-patient-per-month generally increased by LoT ($40,604, $48,630, and $59,499 for second-, third- and fourth-line treatments, respectively). Costs were highest for fourth-line treatment for all healthcare resource utilization categories. Sensitivity analysis findings were consistent with the overall analysis, indicating results were not confounded by the COVID-19 pandemic.

There was potential misclassification of LoT; claims data were processed through an algorithm, possibly introducing errors. A low number of patients met the inclusion criteria. Patients who switched insurance plans, had insurance terminated, or whose enrollment period met the end of data availability may have had truncated follow-up, potentially resulting in underestimated costs.

Total healthcare costs increased with each additional LoT in the R/R DLBCL setting. Further improvements of first-line treatments that reduce the need for subsequent LoTs would potentially lessen the economic burden of DLBCL.