In a nutshell
This study looked at three different immune checkpoint inhibitors and how effective they were at treating patients with non-small-cell lung cancers (NSCLC) with different levels of PD-L1 protein. The authors found that all three drugs analyzed were more effective than chemotherapy for these patients.
Many tumor cells have a protein called PD-L1 which stops the immune system from killing them. New therapies that block PD-L1 are available. These therapies are called immune checkpoint inhibitors (ICIs). They allow the immune system to recognize and kill the cancer cells.
ICIs are now recommended over chemotherapy for patients with NSCLC with high levels of PD-L1. There are three common ICIs, pembrolizumab (Keytruda), nivolumab (Opdivo) and atezolizumab (Tecentriq). Patients with NSCLC have different levels of PD-L1 protein. It is important to understand which drug would be most effective depending on the levels of PD-L1.
Methods & findings
This study analyzed 7 clinical trials on the effectiveness of ICIs in patients with NSCLC, depending on patients PD-L1 levels. In each trial, ICIs were compared to chemotherapy in terms of overall survival (OS, total time patients are alive). Overall, 3688 patients were analyzed. They were separated into 3 groups, based on PD-L1 levels. Group 1 had low levels of PD-L1, group 2 had medium PD-L1 levels and group 3 had high PD-L1 levels.
Overall, ICIs were more effective than chemotherapy for all patient groups. Patients in group 1 treated with ICIs had a 22% higher OS compared to those who received chemotherapy. Group 2 patients had a 16% higher OS with ICIs than with chemotherapy. Group 3 had a 45% better OS with ICIs compared to chemotherapy.
For group 1, nivolumab and atezolizumab improved OS by 21% and 23% compared to chemotherapy. For group 2, pembrolizumab lead to a 24% improved OS compared to chemotherapy. For group 3 all three ICI drugs were effective. In this group, the most effective was atezolizumab, with a 58% improvement in OS compared to chemotherapy.
In patients where ICIs were used as second-line or later treatment, atezolizumab was the most effective for group 1. Nivolumab and pembrolizumab were the most effective for group 2. Although all three drugs were effective for group 3, nivolumab resulted in the best improvement in OS.
The bottom line
The authors concluded that PD-L1 levels could be used as an indicator of treatment and of which specific ICI to use. They found that ICIs were particularly effective for patients with high levels of PD-L1.
The fine print
This study did not give details on side effect rates between each ICI.
Published By :
Aug 06, 2018