Abstract 638P
Background
This study aimed to provide insights into the burden of infection in patients with multiple myeloma (MM) with or without secondary immunodeficiencies (SID).
Methods
In this retrospective cohort study, data were extracted from the Optum-Humedica electronic record database during the period 01-Oct-2015 to 10-Mar-2020, which included a 6-month pre-index period (PIP) and 12-month follow-up following patient identification. Patients aged ≥18 years with a confirmed diagnosis of MM in the PIP were included in the analysis and stratified into two cohorts: those with (SID cohort) and those without SID (no-SID cohort). If a patient had SID or primary immunodeficiencies in the PIP, they were excluded. The first occurrence of a hypogammaglobulinemia ICD-10 code, or a low (<5.0 g/L) serum Immunoglobulin G level was defined as the SID index date.
Results
Of patients with MM, 870 with SID and 3768 without SID were included (mean age: 66.5 and 68.7 years; males: 54.3% and 53.6%; respectively). At 12-month follow-up, significantly more patients in the SID cohort experienced ≥1 infection than the no-SID cohort (58.9% vs 32.1%, p<0.001). A similar pattern was observed for mean number of infections, patients experiencing ≥1 severe bacterial infection or ≥1 infection-associated hospitalization (Table). The most common infection in both cohorts was bacterial: SID, mean (standard deviation [SD]) number of bacterial infections 6.83 (8.04) and no-SID, 4.73 (6.57), p<0.001. Kaplan–Meier analysis showed overall survival (OS) at 24 months was lower in the SID cohort (74.9% of patients alive) than the no-SID cohort (81.8%). Table: 638P
Outcome measures at 12 months
| SID n=870 | No-SID n=3768 | p value SID vs no-SID | |
| Number of infections, mean (SD) | 7.07 (9.23) | 4.58 (6.45) | <0.001 |
| Patients with ≥1 severe bacterial infection,a n (%) | 276 (31.7) | 510 (13.5) | <0.001 |
| Patients with ≥1 hospitalization associated with any infection, n (%) | 231 (26.6) | 350 (9.3) | <0.001 |
| Number of hospitalizations, mean (SD) | 6.55 (8.65) | 5.47 (6.90) | 0.11 |
| Length of hospital stay, mean (SD), days | 13.02 (34.95) | 9.69 (26.88) | 0.22 |
aDefined using ICD-10 codes for bacteremia or sepsis, bacterial meningitis, osteomyelitis/septic arthritis, bacterial pneumonia and visceral abscess.
Conclusions
Patients with MM and SID have a substantially higher burden of infection and healthcare resource use, and lower OS than those without SID. Understanding this burden will allow for earlier targeted treatment of individuals at risk of SID. Study/medical writing support funder: Takeda Development Center Americas, Inc.
Clinical trial identification
Editorial acknowledgement
Medical writing services provided by Oxford PharmaGenesis Ltd, were funded by Takeda Development Center Americas, Inc.
Legal entity responsible for the study
Takeda Development Center Americas, Inc.
Funding
Takeda Development Center Americas, Inc.
Disclosure
J. Richter: Financial Interests, Personal and Institutional, Speaker’s Bureau: BMS, Janssen; Financial Interests, Personal and Institutional, Advisory Board: BMS, Adaptive Biotechnologies, AstraZeneca, Celgene, Janssen, Karyopharm, Oncopeptides, Sanofi, Takeda, Secura Bio, X4 Pharmaceuticals. C. Anderson-Smits: Financial Interests, Personal, Full or part-time Employment: Takeda Development Center Americas, Inc. K. Ren: Financial Interests, Personal, Full or part-time Employment: Takeda Development Center Americas, Inc. M. Kamieniak: Financial Interests, Personal and Institutional, Full or part-time Employment: Takeda Pharma. D. Shah: Financial Interests, Personal, Full or part-time Employment: Takeda Development Center Americas, Inc. C. Siffel: Financial Interests, Personal, Full or part-time Employment: Takeda Development Center Americas, Inc.