The effect of concomitant drugs on oncological outcomes in patients treated with immunotherapy for metastatic urothelial carcinoma: a narrative review

Background: immune checkpoint inhibitors (ICIs) have revolutionized the treatment of metastatic urothelial carcinoma (mUC), significantly improving survival outcomes. However, a subset of patients do not respond to ICIs, prompting research into potential predictive factors. Commonly prescribed medications such as corticosteroids, proton-pump inhibitors (PPIs), antibiotics (Abs), antihypertensives, and analgesics may influence ICI effectiveness. Methods: we conducted a literature search on PubMed to investigate the impact of concomitant medications on the outcomes of patients with mUC, treated with ICIs. We selected the most relevant studies and performed a narrative review. Results: corticosteroids, PPIs and Abs have been associated with reduced survival in ICI-treated patients, including those with mUC. In contrast, antihypertensive agents like renin-angiotensin system inhibitors and beta-blockers may enhance ICI efficacy, though evidence remains inconclusive. The impact of other medications, such as statins, metformin, and analgesics, on ICI outcomes is less clear, with some data suggesting a detrimental impact on immune response. Conclusions: this narrative review synthesizes current evidence on how concomitant medications affect outcomes in mUC patients treated with ICIs.