Background: Rolapitant, a novel NK-1 receptor antagonist, demonstrated efficacy in the prevention of CINV in pts receiving moderately- or highly emetogenic chemotherapy (MEC; HEC). In this post-hoc analysis, we evaluated safety and efficacy outcomes in pts receiving AC-based therapy, now considered HEC. Methods: This double-blind, active-controlled study randomized pts to oral rolapitant 200 mg plus granisetron 2 mg and dexamethasone 20 mg or granisetron and dexamethasone alone (active control). Complete response (CR=no emesis and no use of rescue medication), no emesis, no significant nausea, and time to emesis or rescue medication during overall, acute, and delayed phases and treatment-emergent adverse events (AEs) are presented. Results: 703 pts received AC-based therapy, of which 97% had breast cancer. CR was significantly higher for rolapitant vs. active control for delayed and overall phases in pts receiving AC-based therapy (Table). Time to first emesis or use of rescue medication was significantly longer with rolapitant vs. active control (between-group comparison, p = 0.032); median was not reached in either treatment arm. A significantly greater proportion of pts on rolapitant (73.0%) vs. active control (60.2%) had no emesis during the overall phase (p < 0.001). Rates of no significant nausea were similar for rolapitant (63.7%) and active control (62.4%) in the overall phase (p = 0.728). Treatment-related AEs (TRAEs) during Cycle 1 occurred in 8.7% and 8.8% of pts on rolapitant vs. active control,. Most frequent TRAEs were constipation (2.9% vs. 2.7%), fatigue (2.3% vs. 2.2%), and headache (2.3% vs. 3.3%). Conclusions: Rolapitant was superior to active control in preventing CINV during delayed and overall phases after AC-based chemotherapy. There were no differences in the safety profile of rolapitant in the pt groups. These results are consistent with the overall pt population in this study. Clinical trial information: NCT01500213; NCT01499849; NCT01500226

* unstratified CMH test