# Efficacy of intensive antiemetic therapy including olanzapine in multiple myeloma patients treated with high-dose melphalan with autologous stem cell transplantation

## TL;DR

This study found that an intensive antiemetic regimen including olanzapine improves control of delayed nausea and vomiting in multiple myeloma patients undergoing high-dose melphalan and stem cell transplantation.

## Contribution

The study introduces an effective four-drug antiemetic regimen including olanzapine for managing delayed CINV in MM patients receiving MEL/ASCT.

## Key findings

- The IAR group had a significantly higher complete response rate in the delayed phase (52.9% vs. 31.4%).
- The IAR was independently associated with improved complete response rates (OR, 2.34; 95% CI, 1.09–5.00).
- The IAR group had a lower incidence of grade 3 nausea in the delayed phase (44.1% vs. 75.9%).

## Abstract

Conditioning with high-dose melphalan (MEL) followed by autologous stem cell transplantation (ASCT) is the standard treatment for multiple myeloma (MM). The optimal regimen to prevent chemotherapy-induced nausea and vomiting (CINV) is unclear. We aimed to retrospectively evaluate the antiemetic effect and safety of a four-drug intensive regimen including olanzapine (OLA) on CINV in MM patients receiving MEL/ASCT.

MEL (200 mg/m2) was administered on day 1, followed by ASCT on day 3. Patients were classified into the standard group (palonosetron and dexamethasone on day 1, and aprepitant on day 1–3), and the intensive antiemetic regimen (IAR) group (palonosetron on day 1, dexamethasone on day 1–2, and aprepitant, and OLA on day 1–5). The primary endpoint was defined as no vomiting and no rescue medications (complete response) in the delayed phase (day 2–5).

There were no significant differences in baseline characteristics between the OLA (n = 68) and standard (n = 54) groups. The complete response rate in the IAR group was significantly higher in the delayed phase (52.9% vs. 31.4%, p < 0.05). Multivariate analysis revealed that the IAR was associated with the complete response rate (OR, 2.34; 95% CI, 1.09–5.00; p = 0.028). The incidence of nausea (grade 3) in the delayed phase was lower in the IAR group (44.1% vs. 75.9%, p < 0.001).

The four-drug intensive regimen including OLA may improve the antiemetic effect on delayed CINV while also ensuring safety in MM patients undergoing MEL/ASCT.