Overall Survival with Pembrolizumab in Breast Cancer | NEJM

Summary

Triple-negative breast cancer is challenging to treat due to its aggressive nature and lack of therapeutic targets. The KEYNOTE-522 trial showed that pembrolizumab, combined with chemotherapy, improved pathological complete response and event-free survival in patients with this disease. The latest findings reveal that pembrolizumab plus chemotherapy significantly improved overall survival compared to placebo, with 60-month survival rates of 86.6% vs. 81.7%. However, the incidence of immune-mediated adverse events was higher with pembrolizumab. These results highlight the potential of pembrolizumab as a key treatment for early-stage triple-negative breast cancer.

Takeaways

• 😀 Triple-negative breast cancer is difficult to treat due to its aggressive growth and lack of therapeutic targets.
• 😀 The KEYNOTE-522 trial tested pembrolizumab, a PD-1 inhibitor, as neoadjuvant and adjuvant therapy for triple-negative breast cancer.
• 😀 The trial showed improvements in pathological complete response and event-free survival with pembrolizumab treatment.
• 😀 The trial's overall survival results have now been reported, indicating the treatment's long-term benefits.
• 😀 The phase 3 trial involved 1174 patients with previously untreated, stage II or III triple-negative breast cancer.
• 😀 Participants were randomly assigned to either pembrolizumab plus chemotherapy or placebo plus chemotherapy in a 2:1 ratio.
• 😀 The treatment regimen included neoadjuvant pembrolizumab with chemotherapy, followed by surgery and adjuvant pembrolizumab.
• 😀 The key secondary endpoint was overall survival, which showed a significant improvement with pembrolizumab treatment.
• 😀 At 60 months, overall survival was 86.6% for the pembrolizumab group versus 81.7% for the placebo group.
• 😀 Adverse events were consistent with previous studies, with a higher incidence of immune-mediated adverse events in the pembrolizumab group.
• 😀 The authors concluded that neoadjuvant pembrolizumab plus chemotherapy followed by adjuvant pembrolizumab improves overall survival compared to chemotherapy alone in early-stage triple-negative breast cancer.

Q & A

What makes triple-negative breast cancer challenging to treat?

Triple-negative breast cancer is challenging to treat due to its aggressive growth characteristics and the lack of specific therapeutic targets.

What was the main focus of the KEYNOTE-522 trial?

The KEYNOTE-522 trial focused on evaluating the effect of pembrolizumab, a PD-1 inhibitor, as neoadjuvant and adjuvant therapy in patients with triple-negative breast cancer, looking at improvements in pathological complete response and event-free survival.

What was the design of the KEYNOTE-522 trial?

The trial was a phase 3, international, double-blind, randomized, placebo-controlled study with 1174 patients. Participants were assigned in a 2:1 ratio to receive either pembrolizumab plus chemotherapy or placebo plus chemotherapy.

What were the treatment regimens for patients in the KEYNOTE-522 trial?

Patients in the trial received neoadjuvant pembrolizumab plus chemotherapy, followed by surgery and adjuvant pembrolizumab, or neoadjuvant placebo plus chemotherapy followed by surgery and adjuvant placebo.

What was the key secondary endpoint of the KEYNOTE-522 trial?

The key secondary endpoint of the trial was overall survival.

What was the outcome of overall survival in the KEYNOTE-522 trial?

Overall survival was significantly improved with pembrolizumab plus chemotherapy compared to placebo plus chemotherapy. The estimated overall survival at 60 months was 86.6% for the pembrolizumab group, compared to 81.7% for the placebo group.

How long was the median follow-up period in the KEYNOTE-522 trial?

The median follow-up period in the trial was 75 months.

What were the adverse event findings in the trial?

Adverse events were similar to those observed in previous analyses. However, as expected, the incidence of immune-mediated adverse events was higher in the pembrolizumab plus chemotherapy group, including a higher incidence of grade 3 or higher immune-mediated adverse events.

What conclusion did the authors draw from the KEYNOTE-522 trial?

The authors concluded that neoadjuvant pembrolizumab plus chemotherapy followed by adjuvant pembrolizumab improved overall survival in patients with early-stage triple-negative breast cancer compared to neoadjuvant chemotherapy alone.

Where can the full trial results be accessed?

The full trial results can be accessed at NEJM.org.