Healthcare Resource Utilization and Cost in Patients with Relapsed/Refractory Classical Hodgkin's Lymphoma Who Received Autologous Stem Cell Transplantation in the US
Authors: Yang Xiaoqin , Desai Kaushal D , Gilligan Adrienne M , Raut Monika , Nahar Akash 
Published: February 2021

Introduction: Limited real-world studies exist on the management of relapsed/refractory (R/R) classical Hodgkin's lymphoma (cHL) patients (pts) who failed autologous stem transplant (auto-SCT) and their subsequent healthcare resource utilization (HRU) and cost. Current treatment options include chemotherapy, a second auto-SCT, allogenic (allo-) SCT, palliative care, or newer therapies like brentuximab vedotin (BV) or programmed death-1 (PD-1) blocking antibodies. Pts eligible for treatment post auto-SCT failure may consume significant resources and using real-world data may inform the place of therapy of newly approved agents. Therefore, the objectives of this study were to compare HRU and cost among R/R cHL pts who received auto-SCT by transplant success and failure.
Methods: This retrospective cohort study used electronic medical record (EMR) data of US pts from a network of oncology practices, including practices affiliated with CancerLinQ, maintained in the Definitive Oncology Dataset. Eligible adult (≥18 years) pts who had a confirmed diagnosis of cHL and ≥1 R/R event that occurred between 2000 to 2019 were included. Treatment patterns included any systemic anti-cancer therapy received post auto-SCT failure. Descriptive analyses examined differences by auto-SCT success vs failure. Auto-SCT failure was defined as having a R/R event or disease progression after receipt of auto-SCT. HRU included hospitalization rates, emergency department (ED) visits, and infused supportive care drugs. Costs (inflated for 2020$) were based on matched Health Care Utilization Project coded events. HRU and costs were reported per patient per month (PPPM) from initial cHL diagnosis (first-line [1L] therapy) through the second R/R event (third-line [3L] therapy) and for 3L among a subset of pts who failed auto-SCT in second line (2L). PPPM was calculated by dividing the total HRU or cost during the observation period by the number of months of the observation period and then averaged across all pts (regardless of being flagged for a specific service).
Results: A total of 157 pts (54.9%) received auto-SCT among the R/R cHL cohort (n=286). Most pts were Caucasian (77.7%) with a median age of 31 years (range: 19-73) at the first R/R event. Median length of follow-up was 11 months from the first R/R event. Nearly all pts (91.7%) received auto-SCT after the start of 2L (68.2%, n=107) and 3L (23.6%, n=37). Approximately 9.6% (n=15) also received allo-SCT in later lines. Among auto-SCT pts, 62.4% (n=98) had a transplant success vs 37.6% (n=59) with a transplant failure. Across these 59 pts, 46 (78.0%) received treatment post auto-SCT failure. Treatment post auto-SCT failure consisted of 21 different anti-cancer regimens (monotherapy or in combination) and included BV (alone or in combination) (37.3%, n=22), chemotherapy (30.5%, n=18), PD-1 therapy (alone or in combination) (6.8%, n=4), other (5.1%, n=3), and allo-SCT (1.7%, n=1). The 59 pts with auto-SCT failure primarily failed in 2L (66.1%, n=39) and 3L (27.1%, n=16). HRU and costs for the 39 pts who failed auto-SCT in 2L were substantial in 3L. Approximately 92.3% of pts had a hospitalization, 30.8% had an ED visit, and 51.3% received infused supportive care treatment in 3L. Monthly costs in 3L were high: hospitalization $3,903, ED visit $130, infused supportive care $279, anti-cancer therapy $64,572, and $69,186 total.
From the start of 1L through the end of 3L, the proportion of pts with a hospitalization was significantly higher for pts who failed auto-SCT (Table). Subsequently, costs were also higher and average length of stay longer. While HRU did not differ, infused supportive care costs were higher for auto-SCT pts. No significant differences in HRU and cost were observed across the two groups for ED visits and oncology setting outpatient visits. Anti-cancer therapy costs were significantly higher for pts who failed auto-SCT. Total monthly costs were higher for pts who failed auto-SCT.
Conclusion: In the real-world setting, almost 40% of R/R cHL pts failed auto-SCT. There appears to be no clear standard of care post auto-SCT failure and using real-world data may inform the place in therapy of newer therapies. The HRU and cost of managing post auto-SCT failure was substantial and highlights the significant unmet need in this population. These findings add to the scarce real-world data on treatment patterns, utilization, and cost among R/R cHL pts who receive auto-SCT.

Disclosures
Yang: Merck & Co, Inc.: Current Employment. Desai:Merck & Co., Inc: Current Employment, Current equity holder in publicly-traded company. Gilligan:ConcertAI: Current Employment; Merck & Co., Inc.: Research Funding. Raut:Merck & Co., Inc.: Current Employment. Nahar:Merck Sharp & Dohme, Corp., a subsididary of Merck & Co., Inc., Kenlworth, NJ, USA: Current Employment.