Travel Burden and Travel Costs of Bispecific Antibodies in Patients with Relapsed/Refractory Diffuse Large B-Cell Lymphoma and Relapsed/Refractory Follicular Lymphoma

Background: Several bispecific antibodies (BsAbs) are approved for the treatment (tx) of relapsed/refractory (R/R) non-Hodgkin lymphoma (NHL), including glofitamab (Glofit) for diffuse large B-cell lymphoma (DLBCL), mosunetuzumab (Mosun) for follicular lymphoma (FL), and epcoritamab (Epcor) for both DLBCL and FL. Real-world data on care delivery factors, such as time toxicity from travel burden, are limited (Gupta et al. JCO 2022). We aim to quantify travel burden and travel costs among patients (pts) with NHL receiving treat-to-progression (TTP; Epcor) or fixed-duration (FD) BsAbs (Glofit or Mosun). Methods: An economic model was developed to estimate total travel costs (TTC) associated with BsAb tx administrations. Number of doses was applied to the model according to each BsAb indication and administration schedule per the FDA Prescribing Information (PI). Mean travel burden was estimated from a retrospective analysis of pts from the 100% Medicare Fee-For-Service database, who were diagnosed with DLBCL or FL between Jan 1, 2022 and Dec 31, 2023, and had received Glofit, Mosun, or Epcor. Mean travel burden was quantified by travel distance (miles) and time (minutes/hours) and calculated based on the one-way trip from each patient's home to the service provider where tx was administered, using centroid 5-digit ZIP codes and Google Maps. We assumed an average travel burden across all BsAbs per administration dose and applied this estimate to the model. TTC included round trip costs (RTC), evaluated using Internal Revenue Service 2024 standard mileage rates, and costs associated with productivity loss (WPC), evaluated using average wage per hour reported by the United States Bureau of Labor Statistics. A 1-year time horizon was used for the base case, and a sensitivity analysis was conducted using mean duration of treatment (DOT), either from each BsAb's pivotal study or estimated from median DOT (methods from Hozo et al. BMC Med Res Methodol 2005). Mean travel burden and costs were reported for Epcor versus (vs) Glofit in DLBCL and Epcor vs Mosun in FL. Results : In DLBCL, Epcor and Glofit require 28 and 14 doses over a 1-year time horizon, respectively; at a mean DOT of 7.8 and 6.5 cycles, number of doses was 20 and 8, respectively. In FL, Epcor and Mosun require 28 and 19 doses over a 1-year time horizon, respectively; at a mean DOT of 9.3 and 8.2 cycles, number of doses was 24 and 10, respectively. Overall mean (standard deviation [SD]) one-way travel distance and time for each dose administration was 80.1 (184.2) miles and 84.5 (165.4) minutes, respectively; 56%, 20%, and 24% of tx administrations involved travelling <30 miles, 30-60 miles, and >60 miles, respectively. Mean travel burden was estimated from 114 pts with NHL: 43 received Glofit or Epcor for DLBCL and 71 received Mosun for FL. Overall, 55% were male, 48% were aged 65-74 years, 76% were non-Latinx White, and 81% lived in urban areas. Over a 1-year time horizon for pts with DLBCL, mean travel burden and costs were higher with Epcor (4,486 miles, 79 hours, and $5,758 [RTC $3,005 and WPC $2,753]) vs Glofit (2,243 miles, 39 hours, and $2,879 [RTC $1,503 and WPC $1,377]); Epcor was associated with an additional cost of $2,879 vs Glofit. At mean DOT, mean travel burden and costs were higher with Epcor (3,204 miles, 56 hours, and $4,113 [RTC $2,147 and WPC $1,967) vs Glofit (1,282 miles, 23 hours, and $1,645 [RTC $859 and WPC $787]); Epcor was associated with an additional cost of $2,468 vs Glofit. Over a 1-year time horizon for pts with FL, mean travel burden and costs were higher with Epcor (4,486 miles, 79 hours, and $5,758 [RTC $3,005 and WPC $2,753]) vs Mosun (3,044 miles, 54 hours, $3,907 [RTC $2,039 and WPC $1,868]); Epcor was associated with an additional cost of $1,851 vs Mosun. At mean DOT, mean travel burden and costs were higher with Epcor (3,845 miles, 68 hours, and $4,936 [RTC $2,576 and WPC $2,360]) vs Mosun (1,602 miles, 28 hours, $2,056 [RTC $1,073 and WPC $983]); Epcor was associated with an additional cost of $2,879 vs Mosun. Conclusions: Travel burden and travel costs in pts with R/R NHL can be considerable for TTP Epcor vs FD BsAbs (Glofit or Mosun). The higher travel burden and travel costs associated with Epcor reflects the more frequent dosing vs Glofit or Mosun; our findings were observed at both mean DOT and 1-year time horizons. Travel burden and travel costs associated with BsAb administrations may provide insight for pts and caregivers during shared decision-making.