What is the recommended dose of adjuvant pembrolizumab (programmed death receptor-1 inhibitor) for the treatment of triple negative breast cancer?

From the Guidelines

The recommended dose of adjuvant pembrolizumab for triple negative breast cancer is 200 mg administered as an intravenous infusion every 3 weeks, for a total treatment duration of approximately one year (up to 9 cycles).

Key Considerations

• This treatment is specifically indicated for patients with high-risk, early-stage triple negative breast cancer (TNBC) who have residual invasive disease following neoadjuvant chemotherapy.
• Pembrolizumab should be used in combination with chemotherapy before surgery, then continued as a single agent after surgery.
• Patients should be monitored for immune-related adverse effects during treatment, including thyroid dysfunction, colitis, pneumonitis, and hepatitis.

Evidence-Based Recommendations

The recommendation is based on the most recent and highest quality study, which suggests that pembrolizumab should be administered every 3 weeks throughout the neoadjuvant phase and for nine 3-week cycles during the adjuvant phase, regardless of pCR status 1.

Important Notes

• The efficacy of pembrolizumab in this setting is based on its mechanism as a PD-1 inhibitor that enhances T-cell immune responses against tumor cells, which is particularly beneficial in TNBC due to its higher immunogenicity compared to other breast cancer subtypes.
• Clinical trials have demonstrated significant improvements in event-free survival with this regimen compared to standard chemotherapy alone.
• The use of dose-dense schedules of chemotherapy, with granulocyte colony-stimulating factor support, should be considered given their documented benefit over non-dose-dense schedules 1.

From the Research

Adjuvant Pembrolizumab in Triple Negative Breast Cancer

The recommended dose of adjuvant pembrolizumab for the treatment of triple negative breast cancer is:

• 200 mg intravenously every 3 weeks for up to 9 cycles 2, 3

Key Findings

• The addition of pembrolizumab to neoadjuvant chemotherapy led to a significantly higher percentage of patients with early triple-negative breast cancer having a pathological complete response at definitive surgery 2
• Neoadjuvant pembrolizumab plus chemotherapy, followed by adjuvant pembrolizumab after surgery, resulted in significantly longer event-free survival than neoadjuvant chemotherapy alone 3
• The estimated event-free survival at 36 months was 84.5% in the pembrolizumab-chemotherapy group, as compared with 76.8% in the placebo-chemotherapy group 3

Safety Profile

• The incidence of treatment-related adverse events of grade 3 or higher was 78.0% in the pembrolizumab-chemotherapy group and 73.0% in the placebo-chemotherapy group 2
• Adverse events occurred predominantly during the neoadjuvant phase and were consistent with the established safety profiles of pembrolizumab and chemotherapy 3