Abstract P1-10-07: Phase 3 comparison of APF530 versus ondansetron, each in a guideline-recommended 3-drug regimen for prevention of chemotherapy-induced nausea and vomiting due to anthracycline + cyclophosphamide (AC)–based highly emetogenic chemotherapy (HEC) regimens: A post hoc subgroup analysis of the MAGIC trial

Abstract

Abstract Background:Managing delayed chemotherapy-induced nausea and vomiting (CINV) associated with HEC is an unmet need. AC-based HEC is often administered to breast cancer patients (pts), a mostly female, high-CINV-risk population. APF530, an extended-release formulation of granisetron, demonstrated superior complete response (CR; no emesis [vomiting, retching] + no rescue medication use) in delayed-phase (>24-120 h) CINV with HEC (ASCO criteria) vs ondansetron (Ond) (65% vs 57%, P=0.014), each combined with a neurokinin-1 antagonist and dexamethasone (Dex) (NCT02106494). This post hoc analysis evaluated efficacy and safety of APF530 in pts receiving AC-based therapy. Methods: In this randomized, double-blind, multicenter trial, pts scheduled to receive single-day HEC were stratified by cisplatin ≥50 mg/m2 yes/no and randomized 1:1 to APF530 500 mg SC (granisetron 10 mg) or Ond 0.15 mg/kg IV. Pts received concomitant Dex 12 mg IV and fosaprepitant 150 mg IV on day 1 and oral Dex on days 2-4. The primary end point was CR in the delayed phase. Secondary and other end points included CR in acute (0-24 h) and overall (0-120 h) phases, and complete control (CC; CR and no more than mild nausea) and total response (TR; CR and no nausea) in acute, delayed, and overall phases. Rates were compared using 95% confidence intervals (CIs) for treatment differences; post hoc analysis was not powered to detect treatment differences in the AC subgroup. Safety assessments included adverse events (AEs), injection-site reactions (ISRs), laboratory parameters, and vital signs. Results: A total of 589/902 pts (65%) in the modified intent-to-treat population received AC-based HEC (APF530 291, Ond 298). Baseline demographics were balanced between treatment arms. The majority of pts in the AC subgroup were female (APF530 99%, Ond 98%). Delayed-phase CR was higher with APF530 vs Ond, approaching statistical significance (APF530 64%, Ond 56%; P=0.062) in the AC subgroup, similar to the benefit seen in the larger study. No appreciable benefit of APF530 vs Ond was observed in the acute phase, and trends favorable to APF530 were observed in the overall phase (Table). APF530 was well tolerated. Most AEs were ISRs, generally mild or moderate, and resolved by end of study. Phase, n (%)APF530OndansetronTreatment DifferenceN=291N=298(95% CI), %Complete responseDelayed185 (64)167 (56)8 (-0.4, 15.4)Overall163 (56)153 (51)5 (-3.4, 12.7)Acute205 (70)204 (69)1 (-5.4, 9.4)Complete controlDelayed171 (59)156 (52)7 (-1.6, 14.4)Overall149 (51)143 (48)3 (-4.9, 11.3 )Acute193 (66)191 (64)2 (-5.5, 9.9)Total responseDelayed119 (41)107 (36)5 (-2.9, 12.8)Overall100 (34)94 (32)2 (-4.8, 10.4)Acute164 (56)173 (58)-2 (-9.7, 6.3) Conclusions: APF530 demonstrated an apparent clinical benefit in delayed-phase CR in pts receiving AC-based HEC, concordant with the statistically significant benefit seen in the overall study population. Prevention of CINV in this patient population continues to be a treatment challenge and further investigation is needed. Citation Format: Schnadig I, Agajanian R, Dakhil S, Taylor C, Wilks S, Cooper W, Mosier M, Payne Y, Klepper M, Vacirca J. Phase 3 comparison of APF530 versus ondansetron, each in a guideline-recommended 3-drug regimen for prevention of chemotherapy-induced nausea and vomiting due to anthracycline + cyclophosphamide (AC)–based highly emetogenic chemotherapy (HEC) regimens: A post hoc subgroup analysis of the MAGIC trial. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-10-07.