STOP-CINV Study: Safety and Efficacy of IV Akynzeo® (Fosnetupitant 235 mg and Palonosetron 0.25 mg) for the Prevention of Chemotherapy-Induced Nausea and Vomiting in Indian Patients

Purpose IV Akynzeo^® (IV fosnetupitant + palonosetron) is the first fixed IV combination designed to target key pathways of emesis, enabling convenient single-dose administration. This study aimed to evaluate the safety and effectiveness of IV Akynzeo^® in a real-world context in India. Methods This open-label, single-arm, multicenter, prospective phase IV trial assessed a single dose of IV Akynzeo^® for the prevention of CINV in patients receiving highly emetogenic or moderately emetogenic chemotherapy (HEC/MEC). IV Akynzeo^® (fosnetupitant 235 mg and palonosetron 0.25 mg) was administered over 30 minutes before the start of chemotherapy. The primary endpoints were the number of patients with drug-related treatment-emergent adverse events (TEAEs) as assessed by the treating physician and the number of patients with TEAEs and serious TEAEs over a period of 10 days (±2 days). The key secondary endpoints were complete response, protection, and control in the acute phase (up to 24 hours), delayed phase (>24-120 hours), extended phase (>120-240 hours), overall phase (0-120 hours), and extended overall phase (0-240 hours). Results A total of 178 patients were enrolled (median age, 48.5 years; 64% male), of whom 176 completed the study. IV Akynzeo^® was well tolerated, with 17 patients (9.55%) reporting 23 adverse events (22 mild and one fatal). No new safety signals were detected. Headache, fatigue, and fever were the most commonly reported AEs. Injection site reactions with IV Akynzeo^® were mild in three patients. The complete response rates with IV Akynzeo^® were as follows: 84.27% (95% CI: 78.01-89.29) in the acute phase, 93.26% (95% CI: 88.52-96.47) in the delayed phase, 96.07% (171 of 178 patients; 95% CI: 92.07-98.40) in the extended phase, 83.15% (95% CI: 76.82-88.33) in the overall phase, and 80.34% (143 of 178 patients; 95% CI: 73.73-85.91) in the extended overall phase. Conclusions IV Akynzeo^® was well tolerated and demonstrated substantial effectiveness in mitigating CINV in patients undergoing HEC/MEC across the acute, delayed, and extended phases.