Aprepitant and granisetron for the prophylaxis of radiotherapy-induced nausea and vomiting after moderately emetogenic radiotherapy for bone metastases: a prospective pilot study

Purpose We evaluated the novel combination of aprepitant and granisetron for the prophylaxis of radiotherapy-induced nausea and vomiting (RINV) among patients receiving moderately-emetogenic radiotherapy for thoracolumbar bone metastases. Methods In this single-centre two-arm nonrandomized prospective pilot study, patients undergoing single-fraction radiotherapy (8 Gy) received aprepitant 125 mg and granisetron 2 mg on the day of radiotherapy and aprepitant 80 mg on each of the first 2 days after the day of radiotherapy. Patients undergoing multiple-fraction radiotherapy (20 Gy in 5 fractions) received aprepitant 125 mg on day 1 of radiotherapy, aprepitant 80 mg on days 3 and 5 of radiotherapy, and granisetron 2 mg on every day of radiotherapy. Symptoms and total medication intake were recorded daily during the acute phase (day 1 of radiotherapy until the first day after the last day of radiotherapy), and the delayed phase (days 2-10 after the last day of radiotherapy). Control of vomiting, retching, and nausea was defined as no symptoms and no use of rescue medication. Results Control rates for single-fraction patients (n = 13) were 100% for acute nausea, 62% for delayed nausea, 100% for acute vomiting and retching, and 85% for delayed vomiting and retching. Control rates for multiple-fraction patients (n = 6) were 67% for acute nausea, 83% for delayed nausea, 67% for acute vomiting and retching, and 83% for delayed vomiting and retching. No grade 3 or 4 toxicities attributable to the study intervention were observed. Conclusions The combination of aprepitant and granisetron was safe and efficacious for the prophylaxis of RINV after both single- and multiple-fraction moderately emetogenic radiotherapy for thoracolumbar bone metastases. Our results require confirmation in a larger population.