Indication : HR+, HER2-negative Breast Cancer
Intervention : Ipatasertib
Company : Roche
Technology : AKT Inhibitor
Results:
146 pts were randomised to IPAT + PAC and 76 to PBO + PAC. Prior therapy was balanced between arms, with (neo)adjuvant CT in 55%, endocrine therapy for aBC in 46%, PI3K/mTOR inhibitor in 24% and CDK4/6 inhibitor in 26%. At data cut-off (17/1/20; median follow-up 12.9 mo) 21% of pts remained on therapy. Median investigator-assessed PFS was 9.3 mo in both arms (HR 1.00, 95% CI 0.71–1.40). Median PFS by independent review committee was 9.2 mo with IPAT + PAC vs. 8.5 mo with PBO + PAC (HR 0.79, 95% CI 0.56–1.13). In both arms, objective response rate was 47% and median response duration was 9.2 mo. Overall survival (OS) results are immature (deaths in 25%). Median PAC duration was 6.9 mo with IPAT + PAC vs. 8.8 mo with PBO + PAC; median duration of IPAT was 8.0 mo and PBO was 9.1 mo. IPAT + PAC was associated with more AEs leading to withdrawal of PAC (26% vs. 13%) or IPAT/PBO (11% vs. 4%). IPAT/PBO dose reductions were more common (34% vs. 8%) but PAC dose reductions (26% vs. 24%) and interruptions (53% vs. 51%) and IPAT/PBO interruptions (43% vs. 43%) were similar. No new safety signals were seen. The most common AEs were diarrhoea (85% vs. 37%; grade ≥3: 12% vs. 1%), alopecia (50% vs. 59%) and nausea (41% vs. 20%)
Conclusion:
Adding IPAT to PAC did not improve efficacy in PIK3CA/AKT1/PTEN-altered HR+ aBC. The IPAT + PAC safety profile was consistent with known AEs of each agent. OS follow-up is ongoing
