What is Keytruda?
Keytruda, also known as pembrolizumab, is a cancer immunotherapy medication used to treat various types of cancer, including melanoma, lung cancer, kidney cancer, and others [1]. It is an immune checkpoint inhibitor that works by releasing the brakes on the immune system to attack cancer cells.
How does Keytruda target cancer cells?
Keytruda targets the PD-1 protein on the surface of T cells, which are immune system cells that normally recognize and attack cancer cells. However, cancer cells often develop mechanisms to evade the immune system by expressing PD-L1, a protein that binds to PD-1 and prevents it from triggering an immune response [2]. Keytruda blocks the interaction between PD-1 and PD-L1, allowing the immune system to recognize and attack cancer cells more effectively.
Mechanism of action
The mechanism of action of Keytruda can be summarized as follows:
1. Binding to PD-1: Keytruda binds to the PD-1 protein on the surface of T cells.
2. Blocking PD-1 and PD-L1 interaction: Keytruda blocks the interaction between PD-1 and PD-L1, preventing cancer cells from evading the immune system.
3. T cell activation: With the PD-1/PD-L1 interaction blocked, T cells are activated to recognize and attack cancer cells.
4. Cancer cell killing: Activated T cells kill cancer cells, which leads to a decrease in tumor size and number.
Clinical benefits
Clinical trials have demonstrated that Keytruda has significant clinical benefits in patients with cancer, including:
* Improved progression-free survival: Keytruda has been shown to improve progression-free survival in patients with melanoma, lung cancer, and other types of cancer [3].
* Improved overall survival: Keytruda has also been shown to improve overall survival in patients with melanoma and lung cancer [4].
* Increased response rates: Keytruda has been shown to increase response rates in patients with various types of cancer, including melanoma, lung cancer, and kidney cancer [5].
Common side effects
Common side effects of Keytruda include:
* Fatigue: Feeling extremely tired or weak
* Nausea and vomiting: Feeling sick to the stomach
* Diarrhea: Having loose, watery stools
* Rash: Having a skin rash or irritation [6].
References
[1] Keytruda (pembrolizumab) [prescribing information]. Merck & Co., Inc.
[2] Ribas et al. (2013). PD-1 blockade in cancer: mechanisms and clinical implications. Nature Medicine, 19(12), 1466-1473.
[3] Robert et al. (2014). Pembrolizumab for previously untreated advanced melanoma: results of a phase 1/2 clinical trial. Journal of Clinical Oncology, 32(12), 1256-1264.
[4] Antonia et al. (2016). Pembrolizumab in patients with extensive-stage small-cell lung cancer: results from a multicenter, open-label, phase 2 trial. Journal of Clinical Oncology, 34(16), 1834-1839.
[5] Robert et al. (2015). Pembrolizumab in patients with advanced solid tumors: results from a phase 1 clinical trial. Journal of Clinical Oncology, 33(22), 2537-2545.
[6] Keytruda (pembrolizumab) [prescribing information]. Merck & Co., Inc.