Phase II randomized glioma study to evaluate efficacy and satisfaction of rolapitant plus ondansetron in preventing chemoradiation-induced nausea and vomiting.

Background: Nausea and vomiting remain feared cancer treatment-related side effects. Antiemetic guideline trials exclude malignant glioma patients. In patients receiving radiation with concurrent temozolomide, chemoradiation-induced nausea; vomiting (cRINV) rates are 35% and 26%, respectively, which reduce quality of life, treatment adherence, and cancer control.

Methods: This randomized phase-II open-label trial, evaluated efficacy, patient preference, and satisfaction of ondansetron (short-acting 5HT3-RA; 3 h-half-life) monotherapy versus rolapitant (long-acting NK1-RA; 180 h-half-life) plus ondansetron in preventing cRINV during 6 weeks of temozolomide (75 mg/m²/day × 42 day) with radiation. Fifty-three eligible patients were randomized to Sequence-A (ondansetron-8 mg days: 1-42, day 22 rolapitant-180 mg) or Sequence-B (rolapitant day 1 plus daily ondansetron). Primary endpoint was percentage achieving cRINV-complete response (no vomiting/antiemetic rescue) during the first 2 weeks of radiation. Secondary endpoints: cRIN/cRIV rates, preference/satisfaction for rolapitant/ondansetron, toxicity, and adherence.

Results: Forty-eight (Sequence-A: 25; Sequnce-B: 23) initiated chemoradiation. Mean age = 53, 58% male, 73% Karnofsky performance status (KPS) > 90%, and 73% glioblastoma. During first 2 weeks of radiation, cRINV-CR was 57% with ondansetron and 74% receiving rolapitant/ondansetron (P = .27). Patient-reported 6-week cRINV-CR was 55% for both arms. First 2-week cRIN rates (38% Sequence-A; 32% Sequence-B) were more than cRIV rates (19% Sequence-A; 0% Sequence-B). Patients receiving ondansetron alone vomited more during the first 2 weeks and overall (26%) than with rolapitant/ondansetron (11%). Among 35 completers, 20% preferred rolapitant/ondansetron, 60% preferred ondansetron, and 20% had no preference (P = .0004). Adverse-events attributable to antiemetics were grade 1-2.

Conclusions: No difference was found in cRINV-CRs between the first 2-week treatments or overall satisfaction. Although not a positive study, less vomiting occurred with rolapitant/ondansetron. While patients prefer ondansetron monotherapy, most perceived better effectiveness with rolapitant/ondansetron.