immune checkpoint inhibitor
Also written as: ICI
A class of immunotherapy drugs that block proteins preventing immune system activation, allowing enhanced anti-tumor immune responses.
Full Definition
Immune checkpoint inhibitors are a revolutionary class of cancer therapeutics that work by blocking inhibitory pathways in the immune system, thereby enhancing the body's natural ability to recognize and destroy cancer cells. These drugs target checkpoint proteins such as PD-1, PD-L1, and CTLA-4, which normally serve to prevent excessive immune activation but can be exploited by tumors to evade immune surveillance. In thoracic oncology, checkpoint inhibitors have dramatically improved outcomes for patients with lung cancer, both as monotherapy and in combination with chemotherapy. Examples include pembrolizumab, nivolumab, and atezolizumab.
Usage
Usage note: Use 'immune checkpoint inhibitor' rather than just 'checkpoint inhibitor' to avoid confusion with other medical uses of checkpoints.
In Context
- "The patient achieved a partial response to the immune checkpoint inhibitor pembrolizumab." — Treatment response assessment
- "Immune checkpoint inhibitors have become standard first-line therapy for PD-L1 positive lung cancers." — Treatment guidelines