2175P - Sex and age-related differences in immunotherapy-induced toxicities

Background

Immune checkpoint inhibitors (ICI) are widely used across various cancers and are associated with immune-related adverse events (irAE) potentially lethal. Therefore, it is important to identify risk factors for developing irAE. Women have a higher risk of AE from cytotoxic therapy, however few studies investigated sex differences with ICI. Elderly remain under-represented in clinical trials, including those with ICI. In this study we aim to detect sex and age differences for toxicities in patients treated with ICI.

Methods

This retrospective study included all cancer patients treated with ICI in a single Portuguese institution between January 2017 to December 2022. Data regarding patient, treatment and toxicity was collected from clinical records. Toxicities were recorded using CTCAE, version 5. A descriptive analysis was performed using SPSS®. The Chi-square test was used for 2 categorical variables: sex (male and female) and age (≥65 and <65).

Results

We included 141 patients with a median age of 66 and the majority (87%) were men. Most patients had lung cancer (76%) and were treated with pembrolizumab (53%). The most reported AE were gastrointestinal (GI) (n=115; 23,8%), cutaneous (n=96; 19,8%) and flu-like symptoms (n=56; 11,6%). Only 14,3% of AE were grade ≥3 and lead to treatment suspension in 11,3% of patients. Women reported a higher mean of AE (4,53 vs 3,19; p=0,03). For grade ≥ 3 toxicities, no differences between sexes were found (5,3% vs 15,6%, p=0,231). Among all AE, no differences were found, except for endocrine AE more likely experienced by women (OR=3,02, p=0,024). There were no differences in all grade and ≥G3 toxicities between age groups with a higher trend in the group ≥ 65 years (18,2% vs 9,3%). In parallel, the elderly discontinued treatment more often (14,3% vs 7,8%) due to toxicity. Patients ≥ 65 years had more all grade GI (OR=2,15; p=0,026) and flu-like AE (OR =2,24; p=0,023). Still, there were more respiratory AE in younger patients (OR=0,21; p=0,006).

Conclusions

Despite study limitations, results showed no sex and age differences in irAE, although women and elderly had a higher number of AE, which translated in higher treatment suspension. This data reinforces the need for further studies to promote age and sex-related interventions in management of irAE.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

ULSM, Hospital Pedro Hispano, Matosinhos.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.