asco@alo33:161961 JSONTXT

Background: Standard antiemetic therapy for chemotherapy-induced nausea and vomiting in high emetogenic chemotherapy HEC is a combination of NK1 receptor antagonist, 5-HT3 receptor antagonist and dexamethasone DEX on day 1-3. This study compared the efficacy of DEX on day 1 to on day 1-3 due to reduce side effects of DEX. Methods: Patients ith a malignant solid tumor to receive HEC containing 50 mgm2 of cisplatin or anthracycline+cyclophosphamide ere randomly assigned to Arm A DEX on day 1-3 or Arm B DEX on day 1 ith NK1 receptor antagonist and palonosetron. Primary endpoint as complete response CR rate defined as no emetic episodes and no rescue medications in the overall 0-120h phase. Secondary endpoints included CR rates in the acute 0-24h and delayed 24-120h phases, severity of nausea, adverse events AEs related to DEX and chemotherapy ith CTCAE ver 4.0 on day 1-5, and quality of life ith EROTC QLQ-C30 on day 5. The planned sample size of 400 provided poer of 80 percent to detect the non-inferiority of Arm B to Arm A ith the non-inferiority margin of difference by 15 percent in CR rate one-sided x3B1;=0.025 . Results: 401pts ere enrolled and 396 pts ere evaluable. Baseline characteristics ere ell-balanced. CR rates in the overall phase ere 46.9 percent in Arm A and 44.0 percent in Arm B risk difference: -2.9 percent, 95 percentCI: -12.6 percent-6.8 percent, P=0.007 for non-inferiority . CR rates in Arm A and in Arm B ere 63.3 percent and 64.5 percent risk difference: 1.2 percent, 95 percent CI: -8.1 percent-10.6 percent, Plt0.001 in the acute phase; 56.6 percent and 51.5 percent risk difference: -5.1 percent, 95 percent CI: -14.8 percent-4.6 percent, P=0.023 in the delayed phase, respectively. The severity of nausea as not significantly different beteen 2 arms on each day. AEs related to DEX depends on the duration of DEX administration: hot flushes on day 4 P=0.013 and 5 P=0.038 and tremor on day 5 P=0.041 ere observed more frequently in Arm A, hile anorexia on day 2 P=0.039 and 3 P=0.006 , depression on day 2 P=0.045 and fatigue on day 2 P=0.001 and 3 P=0.004 ere more in Arm B. Other grade 3 AEs and Global health status in QOL ere similar beteen 2 arms. Conclusions: Administration of DEX can be limited to on day 1 in anti-emetic therapy for HEC. Clinical trial information: UMIN000008867.,J Clin Oncol 34, 2016 suppl; abstr 10019 ,UMIN000008867 ,00:00.0,Patient and Survivor Care