Nivolumab was the first immunotherapy to be approved for the second-line treatment of metastatic renal cell carcinoma (RCC). Although some patients have long-lasting responses to nivolumab, others have limited benefit and the majority of patients will eventually experience disease progression. There has been a lot of research to identify a biomarker for response to nivolumab, such as PD-L1. A recent study published in Cancer Chemotherapy and Pharmacology this month looks at a biomarker called C-reactive protein (CRP) at one month after treatment with nivolumab to predict the response of patients with metastatic RCC to this immunotherapy.
Sixty-four (64) patients with metastatic RCC who were treated with nivolumab were included in the study. Blood samples were taken at the start of nivolumab treatment and one month after treatment. Response to treatment and progression-free survival were also assessed. Patients were followed for a median of 8.3 months. Median progression-free survival was 4.5 months and the median immune-progression-free survival was 5.3 months. In the group of patients who responded, there was a significant decrease in the levels of C-reactive protein in their blood after nivolumab treatment when compared with the baseline, whereas there was a significant increase in the non-responder group.
In conclusion, these results show that C-reactive protein levels at one month after treatment with nivolumab appear to be a promising predictive biomarker for response to nivolumab treatment in patients with metastatic RCC. It is clinically useful to be able to predict the effect within a short period. Further prospective trials are needed to prove these preliminary findings.