Kim S-B et al. – The oral AKT inhibitor, ipatasertib, was studied in patients with triple-negative breast cancer (TNBC), which has a high prevalence of PI3K/AKT pathway activation. The current study shown that progression-free survival was longer in TNBC patients who received ipatasertib than in patients who received placebo.

Methods

• 124 patients with inoperable, locally advanced or metastatic TNBC previously untreated with systemic therapy were enrolled.
• Enrolled patients were randomly assigned to receive intravenous paclitaxel (80 mg/m2 on days 1, 8, and 15) with ipatasertib (400 mg or placebo once per day [days 1–21] every 28 days) until disease progression or unacceptable toxicity.

Results

• Median progression-free survival in the intention-to-treat population was 6.2 months with ipatasertib versus 4.9 months with placebo (HR = 0.60).
• Median progress-free survival in the 48 patients with PTEN-low tumours was 6.2 months with ipatasertib versus 3.7 months with placebo (HR = 0.59).