CAR T-cell therapy offers benefit, reduces health care utilization for older patients with DLBCL
ORLANDO — Older patients with multiple comorbidities can successfully undergo chimeric antigen receptor T-cell therapy for non-Hodgkin lymphoma, according to study results presented at ASH Annual Meeting and Exposition.
Long-term efficacy outcomes were not yet available, but the analysis — based on Medicare claims data — showed nearly three-quarters of patients remained alive 6 months after treatment.
Even in that short time, researchers reported a significant decline in treatment costs and health care utilization — including reduced hospitalization rates, fewer bed days and fewer ED visits — in the post-infusion period compared with the pre-infusion period.
That finding “is suggestive of a successful course of treatment,” according to researcher Karl M. Kilgore, PhD, director of advanced analytics at Avalere, a health care consulting firm.
“The magnitude of difference was not surprising, given that many people have talked about CAR T almost in terms of cure,” Kilgore told Healio. “It is important to emphasize this is exclusive of the cost of treatment itself. We looked at ‘pre’ vs. ‘post,’ with treatment as a separate entity. More recent research suggests the difference may be even larger than what we observed.”
An estimated 74,200 Americans are diagnosed with non-Hodgkin lymphoma each year, according to American Cancer Society. About one-third of them have diffuse large B-cell lymphoma, the most common subtype.
Curative treatment options have been limited for patients with relapsed or refractory DLBCL.
In 2017, the FDA approved two CD19-directed CAR T-cell therapies — tisagenlecleucel (Kymriah, Novartis) and axicabtagene ciloleucel (Yescarta; Kite, Gilead) — for the treatment of patients with relapsed or refractory large B-cell lymphoma who underwent at least two prior systemic therapies.
Most patients included in trials that led to those approvals were middle aged, with median ages of 56 to 58 years.
Kilgore and colleagues used Medicare claims data to assess use of this treatment modality for Medicare recipients aged 60 years and older, many of whom have multiple chronic health issues.
Investigators assessed the demographic and clinical characteristics of these patients, and they also compared health care utilization, costs and outcomes before and after CAR T therapy.
Researchers followed a single-group pretest/posttest design, using data from CMS’ 100% Medicare Fee-for-Service Part A and Part B claims data. They did not evaluate pharmacy claims for oral medications because Part D data for the study period were not available.
“This study provides the first real-world look at patients’ CAR T experience, using the first Medicare fee-for-service claims subsequent to product FDA approvals,” Kilgore said.
The analysis included patients with an indicated lymphoma diagnosis who received CAR T-cell therapy between Oct. 1, 2017, and Sept. 30, 2018.
The initial CAR T infusion and associated inpatient stay — if any — served as the index episode of care.
All patients were continuously enrolled in Medicare Fee-for-Service for 6 months prior and 100 days after the index date to allow for evaluation of patient characteristics and treatments before and after infusion.
Researchers compiled information about baseline demographic and clinical characteristics, including age, sex, census region, original reason for entitlement to Medicare, specific B-cell lymphoma diagnosis, comorbidities and prior history of certain conditions.
Their assessment of utilization and cost before and after CAR T infusion included hospitalizations, ICU transfers and ED visits; however, costs associated with the index episode of care were excluded.
The analysis included 207 patients (median age, 71 years; 60% men; 87% white) who underwent CAR T-cell therapy for DLBCL. Half of the patients underwent CAR T therapy as part of a clinical trial.
Most patients were non-dual eligible (91.5%) and qualified for Medicare due to age (87.6%) rather than disability (12.4%).
The majority of patients (78%) had Charlson Comorbidity Index scores greater than 2 (range, 2-15). About half (51%) of patients had one or more chronic conditions that, in many cases, would have made them ineligible for clinical trials. These included heart disease, chronic obstructive pulmonary disease and chronic kidney disease.
Median length of stay for the CAR T procedure was 17 days. About 45% of patients required an ICU stay (median stay, 13 days).
Nearly three-quarters (73%) of patients remained alive at the end of 6-month follow-up.
Results showed patients spent 17% less time in the hospital 6 months after CAR T infusion than during the 6 months prior to CAR T.
More than half of patients had at least one hospitalization during the 6-month pre-index period, and approximately 20% of them had three or more. Of these, 27.1% were readmitted during the post-index period.
Median length of stay was 7 days in the pre-index period and 5 days in the post-index period.
The number of patients who visited the ED declined by approximately one-third from the pre-infusion period to the post-infusion period.
Overall health care costs — excluding costs associated with the CAR T procedure — were 39% lower in the 6 months after infusion than the 6 months preceding infusion.
Total paid amounts for CAR T from all sources — including Medicare and patient contributions — varied significantly based on whether patients received treatment on a clinical trial, and whether the hospital was reimbursed under standard Medicare prospective payment system for inpatient facilities or through the Prospective Payment System exemption.
Although researchers required continuous enrollment in Medicare Fee-For-Service for 6 months, follow-up data for some patients extends approximately 21 months. Median OS had not been reached.
No patients died during the 6-month post-index period, and fewer than 5% were admitted to hospice care.
Claims data showed evidence that only 7.2% of patients underwent subsequent chemotherapy after CAR T, a finding that suggested the majority of patients had no recurrence within the first 6 months after infusion.
The researchers intend to compare data from this patient population to a cohort of patients with private insurance and to a similar group of patients with DLBCL who did not undergo CAR T-cell therapy in hopes of gleaning additional insights into costs and outcomes. – by Mark Leiser
Reference: Kilgore KM, et al. Abstract 793. Presented at: ASH Annual Meeting and Exposition; Dec. 7-10, 2019; Orlando.
Disclosures: Kilgore reports research funding from Kite Pharma. Please see the abstract for all other authors’ relevant financial disclosures.