Impact of concomitant medication use and immune-related adverse events on response to immune checkpoint inhibitors.

Patients receiving checkpoint inhibitors (CPI) are frequently on other medications for co-morbidities. We explored the impact of concomitant medication use on outcomes.  210 metastatic cancer patients on CPI were identified and association between concomitant medication use and immune-related adverse events with clinical outcomes was determined. Aspirin, metformin, β-blockers and statins were not shown to have any statistically significant difference on clinical benefit. 26.3% patients with clinical benefit developed rash versus 11.8% without clinical benefit (p < 0.05) on multivariate analysis. Use of common prescription and nonprescription medications in patients with multiple co-morbidities appears safe and does not have an adverse effect on CPI efficacy. The presence of rash predicted for a better response.