Is cancer treatment with immune checkpoint inhibitors associated with infection risk?

This study is aimed to evaluate the risk of infection for patients who are treated with immune checkpoint inhibitors (ICI) for solid tumors. The study concluded that in frail patients, ICI therapy alone is safer compared to chemotherapy (CT).  

Immunotherapy is a type of cancer treatment that makes use of the immune system to fight cancer. The cancer cell has some proteins present on the surface that help to turn off the immune system by binding proteins on the surface of the immune cells such as PD-1/PD-L1 or CTLA-4.

Previous studies showed that ICI therapy for cancer patients is associated with fewer side effects compared to CT. However, the occurrence, severity, and risk of infection are not studied in detail in patients receiving ICIs.

The study included data from 36 clinical trials. Overall, 21,451 patients were included. The study involved patients with lung cancer, breast cancer, melanoma, colorectal cancer, and prostate cancer. Patients were treated with either ICIs alone, a combination of ICIs, CT alone, a combination of ICIs+CT, or no active treatment. 

Overall, ICI treatment was associated with a similar risk of infections compared to non-ICI treatments. ICI with single-agent was associated with a 42% lower risk of infections compared to CT alone. However, ICI combined with CT was associated with a 37% higher risk for severe infection.

Compared to no treatment, ICIs alone increased the risk of severe infections by 2.1 times.

The study concluded that ICIs alone reduced the risk of infections compared to CT alone.

This study did not include information about the type of infections reported as side effects. Other risk factors for infections such as additional medical conditions, additional medications, or patients' age were not taken into account. Further studies are needed. 

Discuss the option of the right choice of ICI treatment with your doctor.