1637P - Impact of immune-related adverse events (irAEs) and survival (OS) in a cohort of MPM patients (p) treated with immunotherapy (IT)

Background

Studies in solid tumors reported that p treated with IT who developed irAEs presented favorable OS. CheckMate-743 trial demonstrated survival benefit of IT over chemotherapy in 1^st line. In a post-hoc analysis on 52 p who discontinued treatment due to irAEs, the survival benefit was not negatively impacted. We aimed to assess the impact of irAEs and survival outcomes in our series of p treated with IT.

Methods

Clinical records of MPM patients treated with IT at Vall d´Hebron University Hospital between November 2002 and April 2020 were reviewed. Associations between clinical variables and outcome were assessed with Cox regression models and survival data were calculated by the Kaplan-Meier method.

Results

200 p were reviewed. Patient´s characteristics: median age 68 years (29-88), males: 70%, performance status (PS)1: 70%, epithelioid: 81%. First line chemotherapy was offered to 85% of p (60% cisplatin and 30% carboplatin). Median overall survival (OS) was 20.4 m (CI95% 18.8-23.9). Epithelioid histology, PS 0, and treatment with cisplatin vs carboplatin were associated with significant improvements in OS (p<0.001). Fifty-four p were treated with IT: 11 p in first line, 28 p in second line and 15 p in third line. The type of IT agent was antiCTLA4 (18p), PD1/PD-L1 (12 p), oncolytic virus (6 p), anti-mesothelin (5 p) and other checkpoint-inhibitors (13 p). Median OS for patients no treated with IT was 20.47 m versus 34.7 m for p treated with IT (HR0.3 CI95% 0.1-0.7; p=0.01). In first line setting median OS for patients treated with IT was 39.1 m versus 21.3 m for those p not receiving IT (HR0.6 CI95% 0.6-3.7; p=0.34). Median PFS for p treated with IT was 7. 9 m (CI95% 5.4-14.5). Discontinuation of IT due to irAEs was reported in 22% of p. Median PFS for p who discontinued treatment due to irAEs was 11.9 m vs 5.4 m for p who discontinued treatment for another reason (HR0.4 CI95% 0.2-1.1; p=0.06). Median OS for p who discontinued IT due to irAEs was NR vs 11.56 m for p who discontinued due to another reason (HR0.2 CI95% 0.1-0.8; p=0.02).

Conclusions

In our series of patients with MPM treated with IT, the discontinuation of treatment due to irAEs did not negatively impact in OS.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.