115P - Immune-related adverse events in cancer patients treated with immune checkpoint inhibitors in Germany: A population-based study

Background

Immune checkpoint inhibitors (ICIs), a standard in the treatment of various cancer types, induce immune-related adverse events (irAEs) that can potentially impact any organ. This can lead to discontinuation of ICI therapy, immunosuppression, hospital admissions, and even long-term sequelae. This study assessed irAE incidence among German ICI therapy patients using a German payers’ database.

Methods

Patients aged ≥ 12 years with hepatic or hepatocellular cancer (HCC), non-small cell lung cancer (NSCLC), renal, urothelial, or skin cancer initiating ICI therapy from 2017-2020 were included. Claims were analyzed for irAE diagnoses (ICD-10 codes; International Statistical Classification of Diseases and Related Health Problems, 10th version) within half a year after treatment initiation and grouped by affected organ. Incident cases were defined as patients with irAE diagnoses and no pre-existing irAE diagnoses / autoimmune disease the year before. Number of patients hospitalized due to an irAE was analyzed.

Results

Of 5,805,407 enrollees, 307,141 had one of the defined cancer types, and 6,350 started ICI therapy. Of these, 4,237 (66.7%) were male, with a mean (SD) age of 66.8 (10.7) years. 75.5% of the cohort had NSCLC, 19.9% skin cancer, 19.7% HCC, 18.6% renal, 10.3% urothelial cancer (including double counts for multiple cancers). Every second patient (n=3,163, 49.8%) was hospitalized with an irAE diagnosis within half a year after treatment initiation. Of the study population, a total of 1,996 patients (31.4% [95% CI: 30.3 – 32.6%] had incident irAEs. The most common irAEs detected by this analysis were respiratory (n=744, 11.7% [11.0 – 12.5%] and gastroenterological ones (n=493, 7.8% [7.1 – 8.5%]). In patients with HCC, 33.9% (95% CI: 31.4% - 36.6%, n=424) experienced irAEs, while in those with skin cancer, the incidence was 30.0% (95% CI: 27.6% - 32.6%, n=380).

Conclusions

This German population-based analysis demonstrates that every second patient treated with ICI needed inpatient treatment due to irAE diagnosis within half a year after ICI start. The incidence of irAEs varied across different types of cancer. irAE should be assigned ICD-10 codes to improve the data quality.

Legal entity responsible for the study

The authors.

Funding

Mallinckrodt Pharmaceuticals.

Disclosure

L. Heinzerling: Other, Institutional, Advisory Role: Mallinckrodt Pharmaceuticals. T. Vogelmann: Financial Interests, Institutional, Advisory Role: Mallinckrodt Pharmaceuticals. I.T. Seemann, A. Ingram: Financial Interests, Personal, Full or part-time Employment: Mallinckrodt Pharmaceuticals. T. Schubert: Financial Interests, Institutional, Advisory Role: Mallinckrodt Pharmaceuticals.