Background Delayed chemotherapy-induced nausea and vomiting (dCINV) are common adverse events and appear within 24 h of receiving highly emetogenic drugs: cisplatin, cyclophosphamide, doxorubicin. Most published antiemetic guidelines recommend aprepitant to prevent dCINV. However, authors have not considered: first, a two-drug combination (dexamethasone + metoclopramide), the standard treatment in previous guidelines; and second, no studies have compared aprepitant with the previous two-drug combination deemed valid by authors themselves.

Purpose To assess the efficiency of a dCINV prophylaxis protocol in patients at high risk of emesis.

Materials and methods A protocol/algorithm based on available published trials was designed. This algorithm was applied according to each patient’s needs and was part of pharmacotherapeutic monitoring. Complete response (CR) was defined as no emetic episodes within 5 days of chemotherapy.

The standard/initial regimen consists of dexamethasone + metoclopramide. If this regimen was successful, the treatment was sequentially simplified: dexamethasone + metoclopramide if required; dexamethasone alone; low-dose dexamethasone. If there were indications of loss of efficacy by reducing the treatment, we returned to the previous regimen. If the standard/initial regimen was unsuccessful, the following sequential changes were made: dexamethasone + metoclopramide + lorazepam; aprepitant + dexamethasone + lorazepam.

Endpoints examined were: number of patients achieving CR with each regimen and the costs associated with dCINV prophylaxis. An estimate of the efficiency of the protocol was made, considering how many patients were treated with each prophylactic regimen. These results were compared with those that would have obtained if all the patients had received aprepitant.

Results A total of 256 patients was evaluated (2.5-year period). About 91.8% of patients achieved CR with the standard regimen or less intensive treatment.

Cost of protocol was 1,549.77 €. The cost if all the patients had received aprepitant would have been 14,983.68 euros. The estimated saving was of 89.66%.

Conclusions Only a small percentage of patients needed aprepitant to prevent dCINV. Total costs of dCINV prophylaxis based on the proposed algorithm will be one tenth of the cost of aprepitant-based regimen.

No conflict of interest.