In a nutshell
This article looked at several clinical trials to assess the safety of pembrolizumab (Keytruda) in patients with triple-negative breast cancer (TNBC). The authors found that pembrolizumab had an acceptable safety profile and was effective in treating all stages of TNBC.
Some background
Breast cancer (BC) is one of the most common cancers found in women worldwide. TNBC is a type of breast cancer that does not grow in response to female hormones or the protein HER2. TNBC accounts for 10-15% of all BCs. TNBC is known to be difficult to treat and usually has a poorer prognosis when compared to other forms of BCs.
Pembrolizumab is an immunotherapy drug. It binds to PD-L1, a protein found in cancer cells that block the immune system so they can grow undetected. Therefore, pembrolizumab reactivates the immune system to detect and kill cancer cells. Currently there are limited targeted therapies for TNBC and chemotherapy is mainstay of treatment. The effect of pembrolizumab on different types of TNBC is still not clear.
Methods & findings
The authors analyzed 15 trials for this study. The studies included patients with TNBC treated with pembrolizumab.
Pembrolizumab was well tolerated by all patients with TNBC. The most common side effect was low level of white blood cells. In patients with early-stage TNBC pembrolizumab was more effective when compared to other treatments. A complete removal of the tumor was achieved in 60-64.8% of those treated with pembrolizumab compared to 22-51.2% of those in the control groups.
In advanced-stage TNBC pembrolizumab was as effective as a single-agent chemotherapy and was associated with a better safety profile. Pembrolizumab was found to be effective in treating all stages of TNBC regardless of the amount of PD-L1 protein on cancer cells. Pembrolizumab was associated with a longer survival without cancer progression when compared to patients not taking pembrolizumab.
The bottom line
The authors concluded that pembrolizumab had a good safety profile and was effective in both early-stage and advanced-stage TNBC.
The fine print
Many of the trials analyzed had only one treatment group and did not use a comparison group.
Published By :
Critical reviews in oncology/hematology
Date :
Dec 10, 2020
