This is a randomized, prospective, open-label, single-center clinical trial designed to compare the efficacy and safety of a single-day dexamethasone regimen versus a standard multi-day dexamethasone-containing antiemetic regimen in patients with histologically confirmed Head and Neck cancer receiving cisplatin-based chemotherapy.

Cisplatin is associated with a high risk of chemotherapy-induced nausea and vomiting (CINV). Current antiemetic guidelines recommend a combination of an NK1 receptor antagonist, a 5HT3 receptor antagonist, corticosteroids, and olanzapine. However, prolonged corticosteroid use is associated with adverse effects such as hyperglycemia, immunosuppression, insomnia, and psychiatric disturbances. This study aims to determine whether reducing dexamethasone exposure to a single day provides comparable control of CINV while minimizing steroid-related toxicity.

A total of 150 eligible adult patients will be randomized into two parallel arms.

Arm A will receive Netupitant 300 mg plus Palonosetron 0.5 mg on Day 1, Dexamethasone 12 mg intravenous on Day 1 followed by 8 mg orally on Days 2 to 4, and Olanzapine 5 mg orally once daily for four days.

Arm B will receive Netupitant 300 mg plus Palonosetron 0.5 mg on Day 1, Dexamethasone 8 mg intravenous on Day 1 only, and Olanzapine 5 mg orally once daily for four days.

The primary endpoints include complete response, complete protection, and complete control of CINV during acute, delayed, and overall phases following chemotherapy. Secondary outcomes include safety assessment and evaluation of quality of life using the EORTC QLQ-C30 questionnaire.

The study duration is one and a half years, and all procedures will be conducted in accordance with ICMR ethical guidelines and ICH GCP principles.