Merck Touts Encouraging Event-Free Survival For Keytruda Regime Over Placebo-Chemo Regime In Breast Cancer

Merck & Co Inc MRK has announced positive event-free survival (EFS) data from the pivotal neoadjuvant/adjuvant Phase 3 study KEYNOTE-522 trial of Keytruda (pembrolizumab) in breast cancer.
The trial investigated neoadjuvant (delivered before the primary treatment) Keytruda, plus chemo followed by adjuvant Keytruda as monotherapy (Keytruda regime) compared with neoadjuvant chemotherapy followed by adjuvant placebo in patients with high-risk early-stage triple-negative breast cancer (TNBC).
After a median follow-up of 39 months, the Keytruda regimen reduced the risk of EFS events by 37% versus the chemotherapy-placebo regimen.
Although these data have not crossed the boundary for statistical significance at this fourth interim analysis, there was a 28% reduction in the risk of death with the Keytruda regimen versus the chemotherapy-placebo regimen.
For the combined neoadjuvant and adjuvant phases, treatment-related adverse events (TRAEs) occurred in 98.9% of patients receiving the Keytruda regimen (n=783) and 99.7% of patients receiving the chemotherapy-placebo regimen (n=389).
Severe to life-threatening TRAEs occurred in 77.1% versus 73.3%, respectively.
Infusion reactions of any grade in the combined neoadjuvant and adjuvant phases occurred in 43.6% of patients receiving the Keytruda regimen and 21.9% of patients receiving the chemotherapy-placebo regimen.
Price Action: MRK shares are up 0.30% at $77.85 during the market session on the last check Thursday.