1291PClinical outcomes of immune checkpoint inhibitors in older and younger patients with advanced solid tumours in a real-life setting

Background Age-related immune dysfunction might impair the efficacy of immune checkpoint inhibitors (ICIs) in older patients. We aimed to evaluate, in a real-life setting, if age was associated with long-term clinical outcomes and tolerance of ICIs. Methods All patients receiving an ICI monotherapy [CTLA-4 or PD(L)-1 inhibitors] for the standard treatment of a locally advanced or metastatic cancer were included in this retrospective multicentric series (three hospitals in the Hospices Civils de Lyon, France). The primary endpoint was overall survival (OS). Progression-free survival (PFS) and immune-related adverse events (irAEs) were secondary endpoints. The impact of age was assessed using the threshold of 70 years. Results Between January 2007 and October 2017, 410 patients were included in this series, for a total of 435 lines of treatment. One hundred and fifty lines (34%) were received by patients of 70 years or older. They were administered for a lung cancer (n = 304, 74%), a melanoma (n = 79, 19%) or a urologic cancer (n = 27, 7%). Most of the administered treatments were PD(L)-1 inhibitors (n = 356, 82%). Mean follow-up duration starting at treatment initiation was 46 months in the CTLA-4 cohort, and 20 months in the PD(L)-1 cohort. For both CTLA-4 inhibitors and PD(L)-1 inhibitors, there was no statistical association between age and OS (respectively, HR 0.8, 95% CI: 0.5-1.4; log-rank P = 0.49 and HR = 0.9, 95% CI: 0.7-1.1; Log-rank P = 0.27) or PFS (respectively, HR = 0.7, 95% CI: 0.4-1.1; log-rank P = 0.13 or HR = 0.9, 95% CI: 0.7-1.1; Log-rank P = 0.19) in univariate analysis, and after adjusting on prognosis covariates. Older patients did not have more grade 3-4 irAEs (11% versus 12%, P = 0.87). Conclusions In this large real-world series, the long-term clinical outcomes were not statistically different between patients older or younger than 70 years who had received ICIs as a single agent in standard practice for an advanced solid tumor. Older patients did not have more severe immune-related adverse events. These data suggest that the use of ICI monotherapy for older patients may be safe with no specific monitoring. Legal entity responsible for the study Julien Peron. Funding Has not received any funding. Disclosure All authors have declared no conflicts of interest.