Treatment Patterns, Healthcare Resource Utilization, and Costs of Patients With Chronic Lymphocytic Leukemia or Small Lymphocytic Lymphoma in the US

Abstract

Background: Chronic lymphocytic leukemia (CLL) is the most common type of leukemia among US adults and has experienced a rapidly evolving treatment landscape; yet current data on treatment patterns in clinical practice and economic burden are limited. This study aimed to provide an up-to-date description of real-world characteristics, treatments, and costs of patients with CLL or small lymphocytic lymphoma (SLL).

Materials and methods: Using retrospective data from the Optum Clinformatics DataMart database (January 2013 to December 2021), adults with diagnosis codes for CLL/SLL on two different dates were selected. An adapted algorithm identified lines of therapy (LOT). Treatment patterns were stratified by the index year pre- and post-2018. Healthcare resource utilization and costs were evaluated per patient-years.

Results: A total of 18 418 patients with CLL/SLL were identified, 5226 patients (28%) were treated with ≥1 LOT and 1728 (9%) with ≥2 LOT. Among patients diagnosed with CLL in 2014-2017 and ≥1 LOT (N = 2585), 42% used targeted therapy and 30% used chemoimmunotherapy in first line (1L). The corresponding proportions of patients diagnosed with CLL in 2018-2021 (N = 2641) were 54% and 16%, respectively. Total costs were numerically 3.5 times higher and 4.9 times higher compared with baseline costs among patients treated with 1L+ and 3L+, respectively.

Conclusion: This study documented the real-world change in CLL treatment landscape and the substantial economic burden of patients with CLL/SLL. Specifically, targeted therapies were increasingly used as 1L treatments and they were part of more than half of 1L regimens in recent years (2018-2021).

Keywords: chronic lymphocytic leukemia; economic burden; healthcare administrative claims; treatment.

Figure 1.

Sample selection. Notes: 1. CLL and SLL were identified with ICD-9-CM and ICD-10-CM codes. 2. Patients with one SLL diagnosis and one CLL diagnosis on different dates were included. 3. The earliest of all CLL and SLL diagnoses defines the index date. The baseline period is defined as the 12 months prior to the index date. 4. Diagnosis of MCL was identified using ICD-9-CM diagnosis code 200.4x and ICD-10-CM diagnosis code C83.1x. Abbreviations: allo-HSCT, allogeneic hematopoietic stem cell transplantation; CLL, chronic lymphocytic leukemia; CPT, Current Procedural Terminology; HRU, healthcare resource use; ICD-9/10-CM, International Classification of Diseases, 9th/10th Revision, Clinical Modification; MCL, mantle cell lymphoma; SLL, small lymphocytic lymphoma.

Figure 2.

Treatments received in each line of therapy by patients with CLL/SLL, stratified by period of first diagnosis¹. Notes: 1. The observation period spanned from CLL/SLL diagnosis to the earliest of death, end of continuous enrollment, or end of data availability. 2. A total of 7679 patients had a first diagnosis in the period from 2014 to 2017 (1L, n = 2585; 2L, n = 1048; 3L+, n = 452), and 10 739 had a first diagnosis between 2018 and 2021 (1L, n = 2641; 2L, n = 680; 3L+, n = 195). Abbreviations: 1/2/3L+, first/second/third or later line; CHEMO, chemotherapy; CIT, chemoimmunotherapy; CLL, chronic lymphocytic leukemia; SLL, small lymphocytic lymphoma; TARGET, targeted therapy.