Retrospective study of burden of infection in patients with and without secondary immunodeficiency disease following diagnosis of chronic lymphocytic leukaemia

Introduction: Patients with lymphoid malignancies such as chronic lymphocytic leukaemia (CLL)/small lymphocytic lymphoma (SLL) are at risk of developing secondary immunodeficiency disease (SID), which can lead to increased susceptibility to severe, recurrent or persistent infections. This study evaluated burden of infection in patients with and without SID following diagnosis of CLL/SLL. Methods: This observational, retrospective cohort study was conducted using anonymized data from the Optum-Humedica database in the USA (1-Oct-15–10-Mar-20). Patients with SID (SID cohort) and without SID (no-SID cohort) were identified 1-Apr-16–10-Mar-19 (selection window). The definition of SID included International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) hypogammaglobulinaemia (HGG) codes, low immunoglobulin G (IgG) levels (<5.0 g/L) and signs/symptoms of SID. The SID index date was the earliest occurrence of an ICD-10-CM HGG code or record of low IgG levels. In patients without SID, the index date was randomly assigned to replicate the distribution of index dates in the SID cohort. CLL/SLL diagnosis and baseline characteristics were identified during a 6-month pre-index period. Included patients were aged ≥18 years with a confirmed diagnosis of CLL/SLL. Infection-related outcomes and overall survival were assessed in patients with ≥12-month and ≥3 months follow-up post-index date, respectively. Results: Of patients with CLL/SLL, 502 and 3928 with and without SID, respectively, were included (SID vs no-SID: mean [standard deviation; SD] age 70.6 [9.7] vs. 71.6 [10.5] years; 59.2% vs 57.7% male). At 12-month follow-up, a larger proportion of patients with SID had ≥1 infection than those without SID (SID: 70.1%; no-SID: 30.4%; p < 0.001). Compared with the no-SID cohort, in the SID cohort there was also a higher number of infections (SID vs no-SID: mean [SD]: 8.4 [12.7] vs. 4.1 [5.4]; p < 0.001), proportion of patients with ≥1 SBI (SID: 39.8%; no-SID: 9.2%; p < 0.001) and proportion of patients with ≥1 infection-associated hospitalization (SID: 27.7%; no-SID: 5.8%; p < 0.001). The most common type of infection was bacterial (SID: 63.7%; no-SID: 24.9%); in those patients who experienced an SBI, the most frequently reported infection was bacterial pneumonia. To assess overall survival, 646 and 4719 patients with and without SID, respectively, were included. Overall survival at 24 months was lower in the SID cohort (77.3%) than the no-SID cohort (87.2%). Conclusions: Patients with CLL/SLL who subsequently developed SID had a greater burden of infection than patients who did not develop SID. Increasing understanding of this burden of infection may help to improve outcomes in this population Encore Abstract—previously submitted to EHA 2023 The research was funded by: Takeda Development Center Americas, Inc. Writing support was funded by: Takeda Pharmaceuticals International AG. Keywords: cancer health disparities, chronic lymphocytic leukemia (CLL), indolent non-Hodgkin lymphoma Conflicts of interests pertinent to the abstract M. S. Davids Consultant or advisory role AbbVie, Adaptive Biotechnologies, Aptitude Health, BeiGene, Bioascend, Celgene, Curio Science, Eli Lilly, Janssen, Merck, Research to Practice and Takeda Other remuneration: Grant support (paid to his institution): Bristol Myers Squibb, Secura Bio and Surface Oncology; grant support (paid to his institution) and consulting fees: Ascentage Pharma, AstraZeneca, Bristol Myers Squibb, Genentech, MEI Pharma, Pharmacyclics and TG Therapeutics. J. Richter Consultant or advisory role Adaptive Biotechnologies, AstraZeneca, Bristol Myers Squibb, Celgene, Janssen, Karyopharm Therapeutics, Oncopeptides, Sanofi, Secura Bio, Takeda and X4 Pharmaceuticals. Honoraria: Bristol Myers Squibb and Janssen C. Anderson-Smits Employment or leadership position: Takeda Development Center Americas, Inc. Stock ownership: Takeda M. Kamieniak Employment or leadership position: Takeda Development Center Americas, Inc. Stock ownership: Takeda K. Ren Employment or leadership position: Takeda Development Center Americas, Inc. Stock ownership: Takeda D. Shah Employment or leadership position: Takeda Development Center Americas, Inc. Stock ownership: Takeda C. Siffel Employment or leadership position: Takeda Development Center Americas, Inc. Stock ownership: Takeda