Assessing the impact of aprepitant on response to dose-intensive cyclophosphamide, etoposide, and cisplatin (DICEP).

Background: Despite evidence demonstrating the effectiveness of aprepitant for chemotherapy-induced nausea and vomiting (CINV), its use in stem cell transplant settings across Canada is not standard. While pharmacokinetic data exists, the clinical significance of cytochrome P450 3A4 (CYP 3A4) inhibition of cyclophosphamide by aprepitant is unclear. Reduced activation of cyclophosphamide may reduce the effectiveness of dose-intensive cyclophosphamide, etoposide, and cisplatin (DICEP).

Objectives: To compare response rates to DICEP in patients with Hodgkin lymphoma (HL) and diffuse large B-cell lymphoma (DLBCL) in the presence and absence of aprepitant.

Methods: A retrospective review of patients who received full-dose DICEP for relapsed/refractory HL or DLBCL between June 1995 and September 2018 at the Foothills Medical Centre (FMC) in Calgary, Alberta, Canada was conducted. Descriptive statistics were used to assess response rate, as defined by the 2007 International Working Group response criteria.

Results: Of the 218 patients included in this study, 87.6% of patients in the control group and 88.5% of patients in the aprepitant group responded to DICEP (difference 0.025 [95% CI, -0.066 to 0.114], p = 0.827). Univariate analyses for age, sex, type of cancer, stage of cancer, number of prior relapses, and relapse status were not significant. No significant differences were observed for secondary outcomes.

Conclusion: Response rates to DICEP in relapsed/refractory HL and DLBCL patients were similar regardless of aprepitant use. Considering these results and the effectiveness of aprepitant in CINV, its addition to standard antiemetic therapy in patients receiving DICEP should be given strong consideration in the transplant setting.