The impact of PD-L1 as a biomarker of cancer responses to combo anti-PD-1/CTLA-4

Combination therapy of solid tumors with immune checkpoint inhibitors (ICIs) is a promising and rapidly evolving area of clinical research. Combo nivolumab-ipilimumab therapy has demonstrated potent efficacy in recent years, and PD-L1 expression profile has shown to play a key role in determining the most optimal immunotherapeutic regimen in advanced cancer patients. Here, the focus is over the impact of PD-L1 on combo nivolumab-ipilimumab in advanced solid cancer patients. Interpretations of this review indicate that patient responses to combo nivolumab-ipilimumab can be affected from different levels of PD-L1 expression states. A point required attention is the variations in responses among diverse cancer types or between different doses of the immunotherapy drugs. In general, higher rates of responses are seen with higher PD-L1 expression levels in many cancer types. This, however, is not coincided with survival of patients. Taken all into consideration, it could be asserted that considering PD-L1 as a solo biomarker may not be reliable for predicting clinical efficacy of combo nivolumab-ipilimumab. Thus, a search for other biomarkers or combination of PD-L1 with other factors may be considered for predicting patient responses.

Automated summary

This review focuses on the impact of PD-L1 on combo nivolumab-ipilimumab therapy in advanced solid cancer patients, indicating that patient responses can be affected by different levels of PD-L1 expression. Variations in responses are observed among different cancer types or doses of immunotherapy drugs. Therefore, relying solely on PD-L1 as a biomarker may not be reliable for predicting the clinical efficacy of combo nivolumab-ipilimumab. Other biomarkers or a combination of PD-L1 with other factors should be considered for predicting patient responses.