From the Guidelines
PD-L1 testing is not recommended for routine clinical decision-making in patients with advanced renal cell carcinoma (aRCC) due to its limited utility in predicting treatment response to immune checkpoint inhibitors (ICIs) 1.
PD-L1 Expression and Treatment Response
The role of PD-L1 expression in predicting treatment response to ICIs in aRCC is complex and not fully understood. While some studies suggest that PD-L1 expression may be associated with improved treatment outcomes, others have found that PD-L1-negative patients can still respond to ICIs. For example, in the CheckMate 025 study, PD-L1 expression was analyzed using the 28-8 Dako assay, and results showed that PD-L1 expression was prognostic of poor outcome but not predictive of an overall survival effect with nivolumab monotherapy 1.
Limitations of PD-L1 Testing
There are several limitations to PD-L1 testing, including the use of different assays and antibodies, and discrepancies in defining PD-L1 positivity. These limitations can make it challenging to interpret PD-L1 test results and use them to guide treatment decisions. Additionally, PD-L1 expression can vary within a tumor and between different tumor samples, which can further limit the utility of PD-L1 testing.
Clinical Implications
In clinical practice, PD-L1 testing is not routinely recommended for patients with aRCC. Instead, treatment decisions should be based on other factors, such as tumor histology, patient performance status, and prior treatment history. However, PD-L1 testing may be useful in certain clinical trials or research settings, where it can help to identify patients who are more likely to respond to ICIs.
- Key points to consider:
- PD-L1 testing is not recommended for routine clinical decision-making in aRCC
- PD-L1 expression is not a reliable predictor of treatment response to ICIs
- Treatment decisions should be based on other factors, such as tumor histology and patient performance status
- PD-L1 testing may be useful in certain clinical trials or research settings 1
From the FDA Drug Label
A retrospective scoring of a patient’s tumor PD-L1 status using Combined Positive Score (CPS) was also conducted using the PD-L1-stained tumor specimens used for randomization. Patients were stratified by TC PD-L1 expression (≥1% vs. <1% or indeterminate) The unstratified OS HR for YERVOY with nivolumab (n=164) vs. chemotherapy (n=165) was 0. 97 (95% CI: 0.74,1.26) with median OS of 12 months (95% CI: 10.1,16.0) on the YERVOY with nivolumab arm and 12.2 months (95% CI: 10. 7,14) on the chemotherapy arm. The unstratified OS HR was 0.76 (95% CI: 0.62,0.93) for PD-L1 CPS ≥1 subgroup and 1.0 (95% CI: 0.52,1. 94) for PD-L1 CPS <1 subgroup.
The PD-L1 status is significant in determining the efficacy of ipilimumab and nivolumab.
- Patients with PD-L1 expression ≥1% had a better overall survival with YERVOY and nivolumab compared to chemotherapy.
- The hazard ratio for overall survival was 0.78 for PD-L1 CPS ≥1 subgroup, indicating a reduced risk of death.
- However, for patients with PD-L1 CPS <1, the hazard ratio was 1.0, indicating no significant difference in overall survival between the treatment arms 2.
- Similarly, in the CHECKMATE-274 study, patients with PD-L1 ≥1% had a better disease-free survival with nivolumab compared to placebo, with a hazard ratio of 0.55 3.
From the Research
PD-L1 Laboratory Significance
- PD-L1 expression is a crucial biomarker for predicting the efficacy of immune checkpoint inhibitors in patients with non-small cell lung cancer (NSCLC) 4
- The expression of PD-L1 is closely associated with the progression of human cancers and is a promising biomarker for cancer therapy 5
- PD-L1 serves as a natural receptor for PD-1, and their interaction is one of the important mechanisms by which human tumors generate immune escape 5
Treatment Options Based on PD-L1 Expression
- For patients with <1% PD-L1 expression, platinum-based chemotherapy plus pembrolizumab or nivolumab and ipilimumab is associated with the best survival rates 6
- For patients with 1-49% PD-L1 expression, platinum-based chemotherapy plus pembrolizumab produces better survival than chemotherapy 6
- For patients with ≥50% PD-L1 expression, platinum-based chemotherapy plus pembrolizumab/atezolizumab and pembrolizumab/cemiplimab monotherapy are associated with better survival than chemotherapy 6
- In patients with PD-L1-negative NSCLC, pembrolizumab and chemotherapy (PCT) could be a favorable treatment option 4
Efficacy and Safety of Anti-PD-1/PD-L1 Inhibitors
- Anti-PD-1/PD-L1 inhibitors provide a survival advantage over conventional therapies for the treatment of advanced or metastatic cancer 7
- The efficacy and toxicity of anti-PD-1/PD-L1 inhibitors vary depending on factors such as PD-L1 expression, age, and smoking status 7
- Combination therapy with anti-PD-1 and anti-CTLA-4 inhibitors shows greater response rates than anti-PD-1 antibody alone in melanoma 8