2181P - Effect of different corticosteroid treatment strategies on checkpoint inhibitors pneumonitis outcomes

Background

Immune checkpoint inhibitor (ICIs) has opened a new era in the treatment of malignant tumors, but its clinical application has been severely hindered by various immune-related adverse events. Checkpoint inhibitors pneumonitis (CIP) is one of the most common fatal adverse events.The current guideline-recommended treatment strategies are difficult to achieve precise treatment and efficient coverage of CIP. The optimal timing of ICIs suspension and the initiation and dose of corticosteroids still need to be optimized.

Methods

A total of 121 CIP patients of 672 cancer patients were retrospectively analyzed. The detailed treatment process of CIP patients was recorded. Radiographic changes combined with clinical symptoms classified the outcome of CIP into worsening, stable, and improved.

Results

No association were found between continued ICIs after the diagnosis of CIP and worsened outcome in G1 CIP (p=0.296), but continued ICIs treatment was associated with worse outcomes in G2-4 CIP (p=0.009, adjusted p=0.012). For G2 CIP, prompt corticosteroid treatment is closely related with an improved outcome (p=0.015). Initiating corticosteroid in the acute phase is strongly associated with an improved outcome in G2-4 CIP (p=0.021, adjusted p=0.013). Furthermore, patients in the low-dose corticosteroid group were not only conducive to an improved outcome (p=0.024, adjusted p=0.016), but also reduced the risk of residual irreversible fibrotic lesions in G2-4 CIP (p=0.016, adjusted p=0.018).

Conclusions

For G1 CIP, ICIs may be continued conservatively and its safety is manageable. For G2-4 CIP, ICIs should be terminated and corticosteroid therapy initiated as soon as possible after diagnosis to avoid irreversible damage to lung function. Furthermore, initial low doses of corticosteroids(<1mg/kg/d) appear to be more conducive to favorable outcomes than high doses of corticosteroids.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

This work was supported by Outstanding Youth Project of Shaanxi Province (2020JC-35), Research and development projects in Shaanxi Province (2022ZDLSF04-11), Natural Science Foundation of Shaanxi Province (2022JQ-796), Major project of innovation Fund of Chinese Society of Clinical Oncology-MSD (Y-MSD2020-024), Shaanxi Sanqin Scholars Innovation Team (2021-No. 32), Beijing Science Innovation Medical Development Fund (KC2021-JX-0186-5) and National Natural Science Foundation of China (No. 82272073).

Disclosure

All authors have declared no conflicts of interest.