Olanzapine Reduces Chemotherapy-induced Nausea and Vomiting Compared With Aprepitant in Myeloma Patients Receiving High-dose Melphalan Before Stem Cell Transplantation: A Retrospective Study

Antiemetic prophylaxis regimens in haematologic malignancies patients undergoing a hematopoietic stem cell transplantation. Which is the best standard of care? A systematic review

INTRODUCTION

This systematic review, adhering to PRISMA guidelines, aimed to evaluate the efficacy and safety of antiemetic prophylaxis in haematological patients undergoing high-dose chemotherapy as part of their hematopoietic stem cell transplantation (HSCT) conditioning regimens.

METHODS

We performed a comprehensive search in PubMed, EMBASE, ClinicalTrials.gov and the Cochrane database to identify randomised controlled trials (RCTs) and systematic reviews of antiemetic prophylaxis. Studies in English, French, Italian or Spanish were included. This review is registered with PROSPERO, ID CRD42023406380.

RESULTS

Eight RCTs were analysed. The antiemetic regimens evaluated ranged from monotherapy with 5-Hydroxytryptamine Receptor 3 antagonists (5-HT3RAs) to complex combinations including olanzapine, neurokinin-1 receptor antagonists, 5-HT3RAs and corticosteroids. Complete response rates for triplet or quadruple regimens varied between 23.5% and 81.9%. Although no significant adverse effects were observed, minor symptoms such as diarrhoea, constipation, sedation and headaches were reported.

CONCLUSION

Existing evidence on HSCT antiemetic therapy highlights its benefits but fails to provide clear clinical directions. The choice between triplet and quadruplet therapies for different patient scenarios is still uncertain. Until more detailed research is available, healthcare providers must rely on the latest guidelines and their judgement to customise antiemetic care for each patient's specific needs and risks.

Olanzapine within steroid-sparing antiemetic regimen to prevent chemotherapy-induced nausea and vomiting in patients with acute leukemia receiving multi-day intensive chemotherapy

INTRODUCTION

Olanzapine use for chemotherapy-induced nausea and vomiting (CINV) in hematological malignancies, for multi-day chemotherapy, and with a steroid-sparing antiemetic strategy is poorly understood. This study investigated if olanzapine is associated with improved prevention of CINV when added to a steroid-sparing antiemetic regimen in patients with acute leukemia receiving intensive, moderately emetogenic, multi-day chemotherapy.

METHODS

This was a single-center, retrospective cohort study in patients with acute leukemia. Patients who received olanzapine for CINV prevention were compared to those who did not. All patients received a 5-HT3 antagonist. Adult patients receiving moderately emetogenic, multi-day, intensive chemotherapy for acute leukemia were included. Patients were excluded if they received steroids greater than physiological doses during the study period. The primary endpoint was the complete response of CINV (no emesis or rescue antiemetic usage).

RESULTS

This study included 58 patients, 12 patients received olanzapine and 46 patients were in the control group. Baseline demographics were similar. In the study population, 89.7% had acute myeloid leukemia, median age was 54 (interquartile range 42-63) years, 34.5% were female, 27.6% had prior CINV. Complete response of CINV was similar between groups, 4 (33.3%) and 15 (32.6%) patients in the olanzapine and control groups, respectively. Safety events were similar between groups.

CONCLUSION

Patients with acute leukemia receiving multi-day intensive chemotherapy are at high risk for CINV. The limited data in this study suggests that olanzapine use within a steroid-sparing antiemetic regimen was well tolerated and associated with similar incidence and severity of CINV compared to the control group.

Evaluation of palonosetron, fosaprepitant, and olanzapine as antiemetic prophylaxis for fludarabine and melphalan-based conditioning regimens prior to allogeneic hematopoietic stem cell transplants

BACKGROUND

Limited data are available regarding efficacious antiemetic regimens to prevent chemotherapy-induced nausea and vomiting (CINV) for patients undergoing allogeneic hematopoietic stem cell transplant (HSCT). In patients aged 60 years or older, allogeneic HSCT is associated with improved survival, but tolerability of the transplant is a significant barrier. Fludarabine and melphalan (Flu-Mel) is a frequently utilized multi-day reduced intensity conditioning regimen for allogeneic HSCT. However, the optimal CINV prevention regimen is unknown.

OBJECTIVE

The purpose of this study was to evaluate the efficacy of a novel CINV prophylaxis regimen prior to allogeneic HSCT with Flu-Mel compared to a historical control group.

STUDY DESIGN

This was a retrospective, single-center, cohort review of 123 patients who received a Flu-Mel preparative regimen prior to allogeneic HSCT from January 1, 2019, to September 30, 2022. Fifty-nine patients received high dose ondansetron (HDO) for CINV prevention, while sixty-four patients received a combination of palonosetron, fosaprepitant, and olanzapine (PFO). The primary outcome was average number of rescue antiemetic doses administered per day. A key secondary outcome was time to first rescue antiemetic.

RESULTS

The median number of antiemetic doses used per day was significantly lower in patients who received PFO compared to HDO (1.94 doses [0.31-3.60] vs 3.31 doses [1.61-4.92]; p = 0.002). In addition, use of PFO significantly prolonged the median time to first rescue antiemetic compared to HDO (41.3 h [24.3-122.7] vs 26.2 h [14.7-48.1]; p = 0.016).

CONCLUSION

The combination of palonosetron, fosaprepitant, and olanzapine is an effective antiemetic regimen for patients receiving a Flu-Mel-based preparative regimen.

2023 updated MASCC/ESMO consensus recommendations: prevention of nausea and vomiting following multiple-day chemotherapy, high-dose chemotherapy, and breakthrough nausea and vomiting

PURPOSE

This review is an update of the MASCC/ESMO 2015 recommendations for the prophylaxis of acute and delayed nausea and vomiting induced by multiple-day chemotherapy, high-dose chemotherapy, and breakthrough nausea and vomiting.

METHODS

A systematic literature search was conducted using PubMed from June 1, 2015, through February 1, 2023.

RESULTS

We identified 56 references (16 were duplications or invalid), leaving 40 manuscripts for this search. The panel classified level I evidence (three manuscripts) and level II evidence (14 manuscripts). High-dose chemotherapy and stem cell transplant were discussed in four of these manuscripts, and multiple-day chemotherapy treatment in 15. Some manuscripts covered both topics. Additionally, a search for breakthrough nausea and vomiting resulted in 12 "hits." No new relevant studies were identified.

CONCLUSIONS

The recommendations for patients receiving high-dose chemotherapy with stem cell transplants and patients undergoing multiple-day cisplatin were updated. For patients receiving high-dose chemotherapy for stem cell transplant, a combination of a 5-HT3 receptor antagonist with dexamethasone and aprepitant is recommended. Olanzapine could be considered part of the antiemetic regimen. Patients receiving multiple-day cisplatin should receive a 5-HT3 receptor antagonist plus dexamethasone plus aprepitant plus olanzapine. For patients experiencing breakthrough nausea and vomiting, the available evidence suggests using a single dose of olanzapine daily for 3 days.

Prevalence and predictors of long-delayed (> 120 h) chemotherapy-induced nausea and vomiting (CINV)-a systematic review and individual patient data meta-analysis

INTRODUCTION

Although there have been reports of chemotherapy-induced nausea and vomiting (CINV) beyond 120 h, its overall prevalence has not been systematically examined. The aim of this review and meta-analysis was to report on the prevalence of this long-delayed CINV.

METHODS

This review was registered on PROSPERO (CRD42022346963). PubMed (Medline), Embase, and Cochrane Central were searched from inception until August 2022. Articles were included if they reported on CINV > 120 h after initiation of the chemotherapy regimen and patients received a single-agent highly emetogenic (HEC) or moderately emetogenic (MEC) antineoplastic agent for 1 day alone or in combination with low/minimal emetogenic chemotherapy. For all eligible articles, individual study authors were contacted and requested to provide individual patient-level data of demographics, emetogenicity of chemotherapy regimens, and daily incidence of nausea and vomiting. Forward stepwise logistic regression identified predictors for the incident day's CINV based on prior day's CINV episodes, controlling for patient demographics, and stratified by regimen emetogenicity.

RESULTS

A total of 2048 patients from 2 studies were included in this individual patient data meta-analysis: 1333 patients (65%) received HEC and 715 (35%) received MEC. Among those receiving HEC, 325 (24%) experienced acute, 652 (49%) delayed, and 393 (31%) long-delayed nausea; 107 (8%) experienced acute, 179 (14%) delayed, and 79 (6%) long-delayed vomiting. Among those receiving MEC, 48 (7%) experienced acute, 272 (38%) delayed, and 167 (24%) long-delayed nausea; 12 (2%) experienced acute, 97 (14%) delayed, and 42 (6%) long-delayed vomiting. Nausea in the long-delayed phase was as severe as in the delayed phase. Patients experiencing nausea and vomiting on days 4 and 5 were at significant risk of experiencing long-delayed CINV.

CONCLUSION

While not as prevalent as delayed nausea and vomiting, long-delayed CINV affects a significant proportion of patients and severity is similar. Patients with delayed CINV, specifically on days 4-5, are at risk of experiencing long-delayed CINV.

Multiple-day administration of fosaprepitant combined with tropisetron and olanzapine improves the prevention of nausea and vomiting in patients receiving chemotherapy prior to autologous hematopoietic stem cell transplant: a retrospective study

Chemotherapy-induced nausea and vomiting (CINV) is common in patients with lymphoma and multiple myeloma (MM) receiving high-dose chemotherapy (HDC) followed by autologous stem cell transplantation (ASCT). Despite a standard triple antiemetic regimen of a neurokinin-1 (NK1) receptor antagonist (RA), a 5-hydroxytryptamine-3 (5-HT3) RA, and dexamethasone is recommended, how to control the protracted CINV in ASCT setting remains an intractable problem. Here, we retrospectively analyze CINV data of 100 patients who received either SEAM (semustine, etoposide, cytarabine, melphalan) or MEL140-200 (high-dose melphalan) before ASCT, evaluate the efficacy and safety of multiple-day administration of fosaprepitant combined with tropisetron and olanzapine (FTO), and compare the results to those of patients who received a standard regimen of aprepitant, tropisetron, and dexamethasone (ATD). The overall rate of complete response (CR), defined as no emesis and no rescue therapy, is 70% in the FTO group compared to 36% in the ATD group. Although CR rates are comparable in the acute phase between the two groups, significantly more patients treated by FTO achieve CR in the delayed phase than those treated by ATD (74% vs. 38%, p < 0.001). Moreover, FTO treatment significantly reduced the percentage of patients who are unable to eat, as well as the requirement for rescue medications. Both regimens are well tolerated and most adverse events (AEs) were generally mild and transient. In conclusion, the antiemetic strategy containing multiple-day administration of fosaprepitant is safe and effective for preventing CINV in lymphoma and MM patients, particularly in the delayed phase.

Antiemetic Strategies in Patients Who Undergo Hematopoietic Stem Cell Transplantation

Hematopoietic stem cell transplantation (HSCT) is an integral part of the treatment strategy in patients with a hematological disorder. Chemotherapy-induced nausea and vomiting (CINV) is still an issue in patients who undergo HSCT. While several guidelines for the antiemetic therapy against CINV have been published, there is no detailed information about appropriate antiemetic drugs for each conditioning regimen in HSCT. Various studies reported that the triplet of 5-HT3RA, NK1RA, and dexamethasone appears useful in HSCT. However, each antiemetic has unique adverse effects or interactions with specific drugs. Here, we review the literature relating to clinical trials on the prevention of CINV, and summarize the information to clarify the benefit of antiemetic regimens.

Feasibility of Outpatient Stem Cell Transplantation in Multiple Myeloma and Risk Factors Predictive of Hospital Admission

High-dose chemotherapy followed by autologous stem cell transplantation (ASCT) remains the standard of care for multiple myeloma (MM) patients. Although outpatient ASCT has been shown to be safe and feasible, the procedure is overall rare with most patients in the US undergoing inpatient ASCT. Furthermore, hospitalization rates for patients that undergo outpatient ASCT remain high. Adequate markers that predict hospitalization during outpatient ASCT are lacking, yet would be of great clinical value to select patients that are suited to outpatient ASCT. In this study we aimed to elucidate differences between planned outpatient and inpatient ASCT and further evaluated clinical characteristics that are significantly associated with hospitalization during planned outpatient hospitalization. Factors that were significantly associated with a planned inpatient ASCT included an advanced MM disease stage, worse performance status as well as non-Caucasian race, while low albumin levels and female gender were significantly associated with hospitalization during outpatient ASCT. The results of this analysis provide crucial knowledge of factors that are associated with planned inpatient ASCT and hospitalization during outpatient ASCT and could guide the treating physician in decision-making and further facilitate outpatient transplantation.

Supportive care for the prevention of nausea, vomiting and anorexia in a phase 1B study of selinexor in advanced cancer patients: an exploratory study

INTRODUCTION

Clinical observations of cancer patients treated with selinexor have reported high incidence of nausea and anorexia. The study objective was to investigate the adoption of prophylactic olanzapine for the prevention of nausea, vomiting and anorexia in cancer patients receiving selinexor and standard chemotherapy.

METHODS

We retrospectively reviewed supportive care interventions in patients receiving selinexor and recorded frequency of adverse events (NCI-CTAE). Association between categorical variables were analyzed using Fisher's exact tests; repeated measures analysis was performed to assess weight changes over time.

RESULTS

Of 124 evaluable patients, 83 (66.9%) were female, 93 were white (75.0%), and the most common cancer was ovarian (N = 30, 24.2%). One hundred and four patients (83.9%) received olanzapine, of which 93 (89.4%) were prophylactically treated, the majority (86.5%) receiving low 2.5 mg daily dose. Other anti-emetics included ondansetron in 90 patients (72.6%), dexamethasone prescribed in 50 patients (40.3%) and metoclopramide in 49 patients (39.5%), while aprepitant/fosaprepitant (N = 2, 1.6%) were prescribed infrequently. Cancer patients receiving prophylactic olanzapine (N = 93) compared to patients who never received olanzapine (N = 20) had more Grade 1 + anorexia (31.2% vs 20.0%), less nausea (53.8% vs 70.0%), less vomiting (33.3% vs 40.0%), and increased hyperglycemia (29.0% vs 10.0%), but differences were non-statistically significant. In addition, there was minimal weight loss over time in both groups and no statistically significant differences in weight loss between groups.

CONCLUSION

Prophylactic olanzapine decreased nausea, vomiting and maintained weight over 3 months but did not prevent anorexia in patients receiving selinexor and chemotherapy. Low dose olanzapine was well tolerated but associated with hyperglycemia.

Netupitant/palonosetron without dexamethasone for preventing nausea and vomiting in patients with multiple myeloma receiving high-dose melphalan for autologous stem cell transplantation: a single-center experience

Chemotherapy-induced nausea and vomiting (CINV) is one of the most frequent adverse events compromising quality of life (QoL) in patients undergoing autologous stem cell transplantation (ASCT). However, CINV prophylaxis is still lacking uniformity for high-dose melphalan (HDM), which is used to condition patients with multiple myeloma (MM). Netupitant/palonosetron (NEPA) is administered with dexamethasone (DEXA) for CINV prevention in several chemotherapy regimens. Our study aims to assess the efficacy of NEPA, without DEXA, in preventing CINV in 106 adult patients with MM receiving HDM and ASCT. All patients had antiemetic prophylaxis with multiple doses of NEPA 1 h before the start of conditioning and after 72 h and 120 h. A complete response (CR) was observed in 99 (93%) patients at 120 h (overall phase). The percentage of patients with complete control was 93%. The CR rate during the acute phase was 94% (n = 100). During the delayed phase, the CR rate was 95% (n = 101). Grade 1 nausea and vomiting were experienced by 82% and 12% of the patients, respectively. Grade 2 nausea was reported in 18% and vomiting in 10% of patients. Our results showed, for the first time, that NEPA, without DEXA, was a well-tolerated and effective antiemetic option for MM patients receiving HDM followed by ASCT.

The Benefits of Olanzapine in Palliating Symptoms

OPINION STATEMENT

Olanzapine has become a major drug in the management of chemotherapy-induced nausea and vomiting as a prophylactic agent. In addition, a recent randomized trial has demonstrated its benefits in treating nausea and vomiting associated with advanced cancer. The added benefit to olanzapine is that it also stimulates appetite. As a result, since it treats multiple symptoms associated with advanced cancer, it is likely to become the antiemetic of choice in palliative care at least in the USA. The added benefit of treating insomnia and the avoidance of benzodiazepines should place olanzapine in at the top of the list of drugs to use for patients who do complain of insomnia. There is no good evidence that it potentiates the respiratory depression of opioids unlike benzodiazepines. The evidence is weak that olanzapine in as an adjuvant analgesic. Hopefully, future trials will explore this in greater depth. The benefits of adding olanzapine to potent opioids are that it may reduce craving, drug cues, and opioid misuse. Other symptoms like anxiety and depression may be addressed by the addition of olanzapine to standard antidepressants.

Antiemetic Prophylaxis with Fosaprepitant and 5-HT3-Receptor Antagonists in Pediatric Patients Undergoing Autologous Hematopoietic Stem Cell Transplantation

Background

High-dose myeloablative conditioning prior to autologous hematopoietic stem cell transplantation (autoHSCT) in pediatric patients is usually highly emetogenic. The antiemetic neurokinin-1 receptor antagonist fosaprepitant was safe and effective in children receiving highly emetogenic chemotherapy. Data on fosaprepitant during autoHSCT in children are currently not available.

Methods

A total of 35 consecutive pediatric patients, who received an antiemetic prophylaxis with fosaprepitant (4 mg/kg; single dose, max. 1 x 150 mg/kg BW) and ondansetron (24-hours continuous infusion; 8–32 mg/24h) or granisetron (2 x 40 µg/kg∙d⁻¹) during highly emetogenic conditioning chemotherapy before autoHSCT were retrospectively analyzed, and their results were compared with a control group comprising 35 consecutive pediatric patients, who received granisetron or ondansetron only. The antiemetic efficacy and the safety of the two prophylaxis regimens were compared with respect to three time periods after the first chemotherapy administration (0–24h, >24–120h, >120–240h).

Results

Clinical adverse events and clinically relevant increases/decreases of laboratory markers were similarly low and did not significantly differ between the two study groups (p>0.05). The registered number of vomiting events was significantly higher in the control group in the time periods of 0–24h (64 vs 22 events; p<0.01), >24–120h (135 vs 78 events; p<0.0001), >120–240h (268 vs 105 events; p<0.0001), and the whole observation period 0–240h (467 vs 205 events; p<0.0001). The percentage of patients experiencing vomiting was higher in the control group during the time period of >24–120h (100% vs 74.3%) but not the other analyzed time periods (p>0.05).

Conclusion

The fosaprepitant-based antiemetic prophylaxis was safe, well tolerated and significantly reduced vomiting in children undergoing highly emetogenic chemotherapy prior to autoHSCT. Prospective randomized trials are necessary to confirm these results.

Nausea and vomiting during post-transplantation cyclophosphamide administration

Post-transplantation cyclophosphamide (PTCy) is a new method to prevent graft-versus-host disease after allogeneic hematopoietic cell transplantation. Although the use of dexamethasone is recommended as prophylaxis against chemotherapy-induced nausea and vomiting (CINV) for patients who receive high-dose cyclophosphamide, corticosteroids cannot be used during PTCy administration to exploit depletion of alloreactive T cells. Thus, CINV may not be adequately controlled in this situation. We retrospectively examined antiemetic efficacy of the combination of a 5-hydroxytryptamine-3 receptor antagonist (5-HT₃ RA) and a NK₁ receptor antagonist (NK₁ RA) in 36 patients who received PTCy, and compared this efficacy with that of the same combination together with dexamethasone in 27 patients conditioned with cyclophosphamide and total body irradiation (CY/TBI). The proportion of patients who had no vomiting during the acute phase of PTCy administration was 81%, and was lower than 100% in the CY/TBI group (p = 0.02). Our results suggest that prevention of CINV using 5-HT₃ RA and NK₁ RA during PTCy administration is suboptimal and that addition of antiemetic is necessary in patients who receive PTCy.

Antiemetic prophylaxis in patients undergoing hematopoietic stem cell transplantation: a multicenter survey of the Gruppo Italiano Trapianto Midollo Osseo (GITMO) transplant programs

A survey within hematopoietic stem cell transplant (HSCT) centers of the Gruppo Italiano Trapianto Midollo Osseo (GITMO) was performed in order to describe current antiemetic prophylaxis in patients undergoing HSCT. The multicenter survey was performed by a questionnaire, covering the main areas on chemotherapy-induced nausea and vomiting (CINV): antiemetic prophylaxis guidelines used, antiemetic prophylaxis in different conditioning regimens, and methods of CINV evaluation. The survey was carried out in November 2016, and it was repeated 6 months after the publication of the Multinational Association of Supportive Care in Cancer (MASCC)/European Society for Medical Oncology (ESMO) specific guidelines on antiemetic prophylaxis in HSCT. The results show a remarkable heterogeneity of prophylaxis among the various centers and a significant difference between the guidelines and the clinical practice. In the main conditioning regimens, the combination of a serotonin₃ receptor antagonist (5-HT₃-RA) with dexamethasone and neurokin₁ receptor antagonist (NK1-RA), as recommended by MASCC/ESMO guidelines, increased from 0 to 15% (before the publication of the guidelines) to 9-30% (after the publication of the guidelines). This study shows a lack of compliance with specific antiemetic guidelines, resulting mainly in under-prophylaxis. Concerted strategies are required to improve the current CINV prophylaxis, to draft shared common guidelines, and to increase the knowledge and the adherence to the current recommendations for CINV prophylaxis in the specific field of HSCT.

Prevention of chemotherapy-induced nausea and vomiting after high-dose melphalan and stem cell transplantation: review of the evidence and suggestions

INTRODUCTION

High-dose melphalan (HDMel) is the most common conditioning chemotherapy regimen for autologous stem cell transplantation (SCT) in patients affected by multiple myeloma (MM). No consensus exists for the emetogenicity or prophylaxis of chemotherapy-induced nausea and vomiting (CINV) in this regimen.

METHODS

Data on the incidence and efficacy/safety of CINV prophylaxis among patients affected by MM undergoing autologous SCT with the HDMel regimen was extracted from electronic databases and analyzed.

RESULTS

Eleven studies involving multiple CINV prophylaxis regimens were identified and included. No consensus on HDMel emetogenicity was reached, but most studies summarized the emetogenicity as moderate-high risk. An aprepitant-based three-drug regimen (aprepitant + serotonin receptor antagonist (5HT3RA) + dexamethasone) showed better efficacy than a two-drug regimen (5HT3RA + dexamethasone) for CINV prevention without increasing the frequency in adverse events.

CONCLUSIONS

The aprepitant-based three-drug regimen should be the regimen of choice for CINV prophylaxis for MM patients undergoing autologous SCT with HDMel conditioning.

Randomized, Placebo-Controlled, Phase III Trial of Fosaprepitant, Ondansetron, Dexamethasone (FOND) Versus FOND Plus Olanzapine (FOND-O) for the Prevention of Chemotherapy-Induced Nausea and Vomiting in Patients with Hematologic Malignancies Receiving Highly Emetogenic Chemotherapy and Hematopoietic Cell Transplantation Regimens: The FOND-O Trial

Evidence supports olanzapine for prophylaxis of chemotherapy-induced nausea/vomiting (CINV) for highly emetogenic chemotherapy; however, most studies focus on solid malignancies and single-day regimens. A randomized, double-blinded, placebo-controlled trial was conducted to compare the addition of olanzapine to triplet therapy (fosaprepitant, ondansetron, dexamethasone [FOND-O]) versus triplet therapy alone (FOND) in preventing CINV in hematology patients receiving single-day and multiple-day highly emetogenic chemotherapy and hematopoietic cell transplant (HCT) regimens (NCT02635984). The primary objective of this study was to compare complete response (CR; no emesis and minimal nausea, <25 mm on a 100-mm visual analog scale) during the overall assessment period (chemotherapy days plus 5 days after). Secondary objectives were the number of emesis, number of rescue medications, percent achieving minimal nausea, and percent achieving complete protection (CP; no emesis, rescue antiemetic, or significant nausea), all of which are reported as acute (chemotherapy days), delayed (5 days after chemotherapy), and overall phases. Olanzapine 10 mg or matching placebo were given on each chemotherapy day and 3 days after. Adults with hematologic malignancy receiving HCT regimens of melphalan, BEAM (carmustine, etoposide, cytarabine, melphalan), busulfan (Bu)/cyclophosphamide (Cy), Bu/fludarabine (Flu), Bu/melphalan, FluCy, FluCy-total body irradiation (TBI), etoposide-TBI, and ICE (ifosfamide, carboplatin, etoposide) or 7+3 chemotherapy regimens were included. An estimated 98 patients were required using alpha = .05 and 80% power. No significant differences existed in baseline characteristics between FOND-O (n = 51) and FOND (n = 50) arms. Mean duration of olanzapine was 7.7 days (range, 4 to 11). Discontinuation for possible adverse events occurred in 3 placebo and 0 olanzapine patients. CR was significantly higher for FOND-O in overall (55% versus 26%, P = .003) and delayed (60.8% versus 30%, P = .001) but not acute (P = .13) phases. Significantly more patients receiving FOND-O achieved no more than minimal nausea in overall (P = .001) and delayed phases (P = .0002), as well as fewer overall mean emesis counts (P = .005). CP rates were not different in any assessment phase (P ≥ .05 each). Within the HCT subgroup (n = 64), the CR, CP, and no significant nausea rates were significantly better for FONDO-O in overall and delayed phases (all P < .05). Analysis within the HCT subgroup revealed significant improvement in outcomes in delayed and overall phases with FOND-O in the autologous but not allogeneic cohort. Addition of olanzapine to an NK-1-based triplet antiemetic regimen significantly improved clinically relevant outcomes in the HCT population.