A prospective, international, randomized, double-blind, placebo-controlled phase 3 trial studied the efficacy of palbociclib + Fulvestrant and placebo + Fulvestrant in patients with hormone receptor (HR)-positive, HER-2-negative advanced breast cancer whose disease progressed after endocrine therapy.
Efficacy of palbociclib combined with Fulvestrant in the treatment of advanced breast cancer
521 patients were recruited and randomly divided into the palbociclib + Fulvestrant treatment group and the placebo + Fulvestrant treatment group. The primary endpoint of the trial was the patient's overall survival.
The trial results showed that the overall survival of the palbociclib + Fulvestrant treatment group was 34.9 months, while the overall survival of the placebo + Fulvestrant treatment group was 28 months, and the palbociclib group improved the overall survival by 6.9 months.
Among 410 patients who were sensitive to previous endocrine therapy, the overall survival of the palbociclib + Fulvestrant treatment group was 39.7 months, and the overall survival of the placebo + Fulvestrant treatment group was 29.7 months, and the palbociclib group improved the overall survival by 10 months.
Among 111 patients who were not sensitive to previous endocrine therapy, the overall survival of the palbociclib + Fulvestrant treatment group was 20.2 months, and the overall survival of the placebo + Fulvestrant treatment group was 26.2 months. At this time, the results were the opposite, and the overall survival of the placebo group was 6 months higher than that of the palbociclib group.
From the above test data, it can be seen that in patients with hormone receptor (HR)-positive and HER2-negative advanced breast cancer who were sensitive to previous endocrine therapy, the overall survival of palbociclib combined with Fulvestrant was longer than that of placebo combined with Fulvestrant, but for patients who were not sensitive to previous endocrine therapy, the effect of palbociclib combined with Fulvestrant was not very significant.

