Mechanisms and latest clinical studies of new NK1 receptor antagonists for chemotherapy-induced nausea and vomiting: Rolapitant and NEPA (netupitant/palonosetron)

RNA sequencing least shrew (Cryptotis parva) brainstem and gut transcripts following administration of a selective substance P neurokinin NK1 receptor agonist and antagonist expands genomics resources for emesis research

The least shrew is among the subset of animals that are capable of vomiting and therefore serves as a valuable research model for investigating the biochemistry, molecular biology, pharmacology, and genomics of emesis. Both nausea and vomiting are associated with a variety of illnesses (bacterial/viral infections, bulimia, exposure to toxins, gall bladder disease), conditions (pregnancy, motion sickness, emotional stress, overeating) and reactions to drugs (chemotherapeutics, opiates). The severe discomfort and intense fear associated with the stressful symptoms of nausea and emesis are the major reason for patient non-compliance when being treated with cancer chemotherapeutics. Increased understanding of the physiology, pharmacology and pathophysiology underlying vomiting and nausea can accelerate progress for developing new antiemetics. As a major animal model for emesis, expanding genomic knowledge associated with emesis in the least shrew will further enhance the laboratory utility of this model. A key question is which genes mediate emesis, and are they expressed in response to emetics/antiemetics. To elucidate the mediators of emesis, in particular emetic receptors, their downstream signaling pathways, as well as the shared emetic signals, we carried out an RNA sequencing study focused on the central and peripheral emetic loci, the brainstem and gut. Thus, we sequenced RNA extracted from brainstem and gut tissues from different groups of least shrews treated with either a neurokinin NK1 receptor selective emetic agonist, GR73632 (5 mg/kg, i.p.), its corresponding selective antagonist netupitant (5 mg/kg, i.p.), a combination of these two agents, versus their corresponding vehicle-pretreated controls and drug naïve animals. The resulting sequences were processed using a de novo transcriptome assembly and used it to identify orthologs within human, dog, mouse, and ferret gene sets. We compared the least shrew to human and a veterinary species (dog) that may be treated with vomit-inducing chemotherapeutics, and the ferret, another well-established model organism for emesis research. The mouse was included because it does not vomit. In total, we identified a final set of 16,720 least shrew orthologs. We employed comparative genomics analyses as well as gene ontology enrichment, KEGG pathway enrichment and phenotype enrichment to better understand the molecular biology of genes implicated in vomiting.

Multiple Gastrointestinal Symptoms Are Associated With Chemotherapy-Induced Nausea in Patients With Breast Cancer

BACKGROUND

Unrelieved chemotherapy-induced nausea (CIN) is a significant problem for patients with breast cancer (BC).

OBJECTIVE

In a sample of patients with BC who were assessed before their second or third cycle of chemotherapy, study purposes were to evaluate for the occurrence, severity, frequency, and distress associated with CIN; evaluate for differences in demographic and clinical characteristics and gastrointestinal (GI) symptom occurrence rates between patients who did and did not report CIN; and determine which demographic, clinical, and symptom characteristics were associated with the occurrence of CIN.

METHODS

Patients completed demographic and clinical questionnaires and the Memorial Symptom Assessment Scale for nausea and common GI symptom assessments. Univariate analyses evaluated for differences in demographic and clinical characteristics and GI symptom occurrence between patients who did and did not report CIN. Multiple logistic regression analysis evaluated for characteristics associated with CIN.

RESULTS

Of the 532 patients with BC, 47.2% reported CIN occurrence. Characteristics associated with CIN group membership were poorer functional status, receipt of chemotherapy on a 14-day cycle, and higher occurrence rates of 5 GI symptoms (ie, dry mouth, vomiting, constipation, change in the way food tastes, and lack of appetite; all P < .001).

CONCLUSIONS

Unrelieved CIN is a common symptom in patients with BC. This study is the first to demonstrate that 5 co-occurring GI symptoms were associated with CIN occurrence.

IMPLICATIONS FOR PRACTICE

This study identified new risk factors for CIN occurrence in patients with BC. Clinicians may be able to initiate additional interventions to alleviate CIN.

Opioid Analgesia and Opioid-Induced Adverse Effects: A Review

Opioids are widely used as therapeutic agents against moderate to severe acute and chronic pain. Still, these classes of analgesic drugs have many potential limitations as they induce analgesic tolerance, addiction and numerous behavioural adverse effects that often result in patient non-compliance. As opium and opioids have been traditionally used as painkillers, the exact mechanisms of their adverse reactions over repeated use are multifactorial and not fully understood. Older adults suffer from cancer and non-cancer chronic pain more than younger adults, due to the physiological changes related to ageing and their reduced metabolic capabilities and thus show an increased number of adverse reactions to opioid drugs. All clinically used opioids are μ-opioid receptor agonists, and the major adverse effects are directly or potentially connected to this receptor. Multifunctional opioid ligands or peripherally restricted opioids may elicit fewer adverse effects, as shown in preclinical studies, but these results need reproducibility from further extensive clinical trials. The current review aims to overview various mechanisms involved in the adverse effects induced by opioids, to provide a better understanding of the underlying pathophysiology and, ultimately, to help develop an effective therapeutic strategy to better manage pain.

A dose-finding randomized Phase II study of oral netupitant in combination with palonosetron .75 mg intravenous for the prevention of chemotherapy-induced nausea and vomiting in Japanese patients receiving highly emetogenic chemotherapy

Objective

Netupitant is a novel, selective neurokinin-1 receptor antagonist used for prevention of chemotherapy-induced nausea and vomiting, a distressing side effect of chemotherapy. This double-blind, randomized, Phase II study investigated the dose-response of oral netupitant in Japanese patients receiving highly emetogenic chemotherapy.

Methods

Chemotherapy-naïve patients were randomized (1:1:1) to a single oral netupitant 30-, 100- or 300-mg dose before chemotherapy initiation. Patients received concomitant palonosetron (0.75 mg intravenously [i.v.] Day 1) and dexamethasone (9.9 mg i.v. Day 1, 8 mg orally Days 2-4).

Results

Overall, 402 patients (30 mg: 134; 100 mg: 135; 300 mg: 133) were treated and evaluable for efficacy and safety. The primary endpoint of overall (0-120 h after chemotherapy administration) complete response (CR) rate (no emesis, no rescue medication) was 64.2%, 60.0% and 54.9% in the 30-, 100- and 300-mg arms, respectively, without statistical significance for dose-response. The safety profile of netupitant was comparable in the three arms. The plasma concentrations of netupitant and its metabolites increased with the dose increase from 30 mg to 300 mg.

Conclusions

No dose-response relationship of netupitant in terms of overall CR rate was observed in this study. Netupitant was well tolerated at all doses without clinically harmful safety signals observed.

Clinical trial registration

JapicCTI-142 483.

Effect of aprepitant administration on CINV caused by cisplatin multi-day chemotherapy and pharmacokinetics of docetaxel

PURPOSE

To compare efficacy and safety of postponing administration of aprepitant and routine triple-antiemetic treatment for chemotherapy-induced nausea and vomiting in patients who received docetaxel and cisplatin multi-day chemotherapy treatment, and to evaluate the effect of aprepitant on docetaxel pharmacokinetics in the Chinese population.

METHODS

A total of 24 cancer patients (including 5 females and 19 males, 22-74 years old) received two cycles of high-emetic DP (docetaxel 75 mg/m² on day 1 + cisplatin 25 mg/m² on days 1-3) regimen. A randomized, two-period and cross-over study was applied for prevention of chemotherapy-induced nausea and vomiting. The patients in group A took aprepitant 125 mg on day 1 and 80 mg on days 2-3 (administered aprepitant 1 h before chemotherapy). In group B, the patients took aprepitant 125 mg on day 2, 80 mg on days 3-4, which was delayed 1 day than group A. Efficacy and safety in overall phase were evaluated within 5 days after initiation of chemotherapy. Simultaneously, the differences in the pharmacokinetic parameters of docetaxel between two different antiemetic treatments are compared.

RESULTS

The CR rate of delayed-phase nausea was compared between the routine triple-antiemetic treatment (group A) and the aprepitant delayed 1-day administration treatment (group B), and the difference was statistically significant (16.7% vs 45.8% P < 0.05), despite there were similar for two groups in the CR rate of acute-phase nausea and vomiting, and delayed-phase vomiting. In two groups, the area under the docetaxel curve (AUC_0-t values) (mean ± SD) of docetaxel was 1134.21 ± 732.55 (ng h/mL) and 1080.94 ± 585.09 (ng h/mL), and the geometric means were 944.82 and 902.10 (ng h/mL), respectively. There was no significant difference in AUC values between the two antiemetic treatments (P > 0.05), as well as C_max, CL_z, T_1/2z, MRT and T_max.

CONCLUSIONS

Delayed administration of aprepitant provided superior delayed-phase nausea protection for patients who received cisplatin-based chemotherapy in comparison with the routine triple-antiemetic treatment. In addition, in the routine triple-antiemetic treatment, aprepitant did not significantly affect the main pharmacokinetic parameters of docetaxel.

Intracellular emetic signaling cascades by which the selective neurokinin type 1 receptor (NK1R) agonist GR73632 evokes vomiting in the least shrew (Cryptotis parva)

To characterize mechanisms involved in neurokinin type 1 receptor (NK₁R)-mediated emesis, we investigated the brainstem emetic signaling pathways following treating least shrews with the selective NK₁R agonist GR73632. In addition to episodes of vomiting over a 30-min observation period, a significant increase in substance P-immunoreactivity in the emetic brainstem dorsal motor nucleus of the vagus (DMNX) occurred at 15 min post an intraperitoneal (i.p.) injection GR73632 (5 mg/kg). In addition, time-dependent upregulation of phosphorylation of several emesis -associated protein kinases occurred in the brainstem. In fact, Western blots demonstrated significant phosphorylations of Ca²⁺/calmodulin kinase IIα (CaMKIIα), extracellular signal-regulated protein kinase1/2 (ERK1/2), protein kinase B (Akt) as well as α and βII isoforms of protein kinase C (PKCα/βII). Moreover, enhanced phospho-ERK1/2 immunoreactivity was also observed in both brainstem slices containing the dorsal vagal complex emetic nuclei as well as in jejunal sections from the shrew small intestine. Furthermore, our behavioral findings demonstrated that the following agents suppressed vomiting evoked by GR73632 in a dose-dependent manner: i) the NK₁R antagonist netupitant (i.p.); ii) the L-type Ca²⁺ channel (LTCC) antagonist nifedipine (subcutaneous, s.c.); iii) the inositol trisphosphate receptor (IP₃R) antagonist 2-APB (i.p.); iv) store-operated Ca²⁺ entry inhibitors YM-58483 and MRS-1845, (i.p.); v) the ERK1/2 pathway inhibitor U0126 (i.p.); vi) the PKC inhibitor GF109203X (i.p.); and vii) the inhibitor of phosphatidylinositol 3-kinase (PI3K)-Akt pathway LY294002 (i.p.). Moreover, NK₁R, LTCC, and IP₃R are required for GR73632-evoked CaMKIIα, ERK1/2, Akt and PKCα/βII phosphorylation. In addition, evoked ERK1/2 phosphorylation was sensitive to inhibitors of PKC and PI3K. These findings indicate that the LTCC/IP₃R-dependent PI3K/PKCα/βII-ERK1/2 signaling pathways are involved in NK₁R-mediated vomiting.

Risk factors associated with chemotherapy-induced nausea and vomiting in the triplet antiemetic regimen including palonosetron or granisetron for cisplatin-based chemotherapy: analysis of a randomized, double-blind controlled trial

PURPOSE

The triplet antiemetic regimen is recommended for cisplatin-based highly emetogenic chemotherapy, in the current guidelines for antiemetic prophylaxis. Although risk factors related to chemotherapy-induced nausea and vomiting (CINV) have been identified by several prior studies, there are only few studies evaluating risk factors associated with the prophylactic triplet antiemetic therapy, particularly in palonosetron use. The present study aimed to reveal the risk factors related to CINV development in patients receiving cisplatin and to compare CINV risk factors between palonosetron and granisetron use.

METHODS

In total, 825 patients in a phase III trial receiving palonosetron with graniestron were evaluated. Multivariate logistic regression models were used to predict risk factors associated with CINV development. Additionally, risk factors associated with CINV development were separately evaluated in each treatment group.

RESULTS

Multivariate analysis of the entire study group revealed that sex, age, cisplatin dose, and granisetron use were significant and independent factors affecting CINV development in the overall phase. Similarly, sex and age were risk factors for CINV in both treatment groups. Kaplan-Meier curves classified by each treatment group showed no significant difference between the groups among patients without any risk factors for CINV (P = 0.353). Conversely, complete response rates for patients with at least one risk factor were higher in patients receiving palonosetron (P = 0.049).

CONCLUSIONS

This analysis revealed the importance of previously reported CINV risk factors when using triplet antiemetics. Palonosetron might be preferred for patients with at least one risk factor.

Meta-analysis of safety and efficacy of rolapitant, NK-1 receptor antagonist for prevention of chemotherapy-induced nausea and vomiting

Although chemotherapeutic agents represent a cornerstone of cancer treatment, chemotherapy-induced nausea and vomiting (CINV) affect the patients' quality of life and basic daily activities. Rolapitant is a novel selective neurokinin-1 receptor antagonist (NK-1 RA), which was clinically approved for prevention of CINV. The aim of the present study is to synthesize evidence about the safety and efficacy of rolapitant in combination with other antiemetic agents for prophylaxis against CINV. We performed a web-based literature search of six authentic databases to identify eligible studies. Safety and efficacy endpoints were extracted and pooled as odds ratios (ORs) in a fixed-effect meta-analysis model, using Comprehensive Meta-Analysis software for windows. Five randomized controlled trials (n = 2984) were pooled in the final analysis. Rolapitant (180mg) in combination with a serotonin-3 (5-HT3) receptor antagonist and dexamethasone was superior to placebo plus 5-HT3 receptor antagonist and dexamethasone in term of complete response rate in the acute (OR = 1.4, 95% CI [1.16, 1.7]) and the delayed phases (OR = 1.68, 95% CI [1.44, 1.96]). Moreover, rates of complete protection were significantly higher with rolapitant 180mg than with placebo in the overall, acute, and delayed phases (OR = 1.52, 95% CI [1.3, 1.76]), OR = 1.24, 95% CI [1.04, 1.49], and OR = 1.5, 95% CI [1.29, 1.75]), respectively. In conclusion, rolapitant in combination with a 5-HT3 receptor antagonist and dexamethasone is well tolerated and more effective than 5-HT3 receptor antagonist plus dexamethasone for the prevention of CINV.

From receptor binding kinetics to signal transduction; a missing link in predicting in vivo drug-action

An important question in drug discovery is how to overcome the significant challenge of high drug attrition rates due to lack of efficacy and safety. A missing link in the understanding of determinants for drug efficacy is the relation between drug-target binding kinetics and signal transduction, particularly in the physiological context of (multiple) endogenous ligands. We hypothesized that the kinetic binding parameters of both drug and endogenous ligand play a crucial role in determining cellular responses, using the NK1 receptor as a model system. We demonstrated that the binding kinetics of both antagonists (DFA and aprepitant) and endogenous agonists (NKA and SP) have significantly different effects on signal transduction profiles, i.e. potency values, in vitro efficacy values and onset rate of signal transduction. The antagonistic effects were most efficacious with slowly dissociating aprepitant and slowly associating NKA while the combination of rapidly dissociating DFA and rapidly associating SP had less significant effects on the signal transduction profiles. These results were consistent throughout different kinetic assays and cellular backgrounds. We conclude that knowledge of the relationship between in vitro drug-target binding kinetics and cellular responses is important to ultimately improve the understanding of drug efficacy in vivo.

"Systemic strategy at the patient's service": a congress report on supportive care in oncology

None.

The anti-asthmatic drug pranlukast suppresses the delayed-phase vomiting and reverses intracellular indices of emesis evoked by cisplatin in the least shrew (Cryptotis parva)

The introduction of second generation serotonin 5-HT₃ receptor (5-HT₃) antagonist palonosetron combined with long-acting substance P neurokinin NK₁ receptor (NK₁) antagonists (e.g. netupitant) has substantially improved antiemetic therapy against early- and delayed-phases of emesis caused by highly emetogenic chemotherapeutics such as cisplatin. However, the improved efficacy comes at a cost that many patients cannot afford. We introduce a new class of antiemetic, the antiasthmatic leukotriene CysLT1 receptor antagonist pranlukast for the suppression of cisplatin-evoked vomiting. Pranlukast (10mg/kg) by itself significantly reduced the mean frequency of vomits (70%) and fully protected least shrews from vomiting (46%) during the delayed-phase of cisplatin (10mg/kg)-evoked vomiting. Although, pranlukast tended to substantially reduce both the mean frequency of vomits and the number of shrews vomiting during the early-phase, these reductions failed to attain significance. When combined with a first (tropisetron)- or a second (palonosetron)-generation 5-HT₃ receptor antagonist, pranlukast potentiated their antiemetic efficacy during both phases of vomiting. In addition, pranlukast by itself prevented several intracellular signal markers of cisplatin-evoked delayed-vomiting such as phosphorylation of ERK1/2 and PKA. When pranlukast was combined with either palonosetron or tropisetron, these combinations suppressed the evoked phosphorylation of: i) ERK1/2 during both acute- and delayed-phase, ii) PKCα/β at the peak acute-phase, and iii) PKA at the peak delayed-phase. The current and our published findings suggest that overall behavioral and intracellular signaling effects of pranlukast via blockade of CysLT1 receptors generally appear to be similar to the NK₁ receptor antagonist netupitant with some differences.

Concise review of the management of iatrogenic emesis using cannabinoids: emphasis on nabilone for chemotherapy-induced nausea and vomiting

Chemotherapy-induced nausea and vomiting (CINV) is a prevalent, distressing, and burdensome side effect of cancer chemotherapy. It is estimated to affect the majority of patients receiving certain anti-cancer drug regimens and can be treatment-limiting, even for life-saving medications. Despite seemingly numerous options, such as antimuscarinic anticholinergics, antihistamines, 5-HT₃ receptor antagonists, dopamine receptor antagonists, and neurokinin-1 receptor antagonists, preventative therapies are often inadequately effective, particularly for "delayed CINV"-leaving an important unmet clinical need. Cannabinoid receptor agonists, by virtue of their unique mechanism of action and efficacy and safety data reported in clinical trials, appear to offer a useful additional option. The mechanistic value of cannabinoids has been well known for many years, but these agents may have been underutilized in the past because of the notoriety and legal status of marijuana. While botanical marijuana contains nearly 500 components, including the psychoactive tetrahydrocannabinol (THC), nabilone is an established, single-entity synthetic cannabinoid receptor agonist that has become the focus of renewed interest. We review the basic pharmacology and clinical trial data of nabilone for use in prophylaxis and treatment of CINV.

Prevention of chemotherapy-induced nausea: the role of neurokinin-1 (NK1) receptor antagonists

Chemotherapy-induced nausea (CIN) has a significant negative impact on the quality of life of cancer patients. The use of 5-hydroxytryptamine-3 (5-HT₃) receptor antagonists (RAs) has reduced the risk of vomiting, but (except for palonosetron) their effect on nausea, especially delayed nausea, is limited. This article reviews the role of NK₁RAs when combined with 5-HT₃RA–dexamethasone in CIN prophylaxis. Aprepitant has not shown consistent superiority over a two-drug (ondansetron–dexamethasone) combination in nausea control after cisplatin– or anthracycline–cyclophosphamide (AC)-based highly emetogenic chemotherapy (HEC). Recently, dexamethasone and dexamethasone–metoclopramide were demonstrated to be non-inferior to aprepitant and aprepitant–dexamethasone, respectively, for the control of delayed nausea after HEC (AC/cisplatin), and are now recognized in the guidelines. The potential impact of the new NK₁RAs rolapitant and netupitant (oral fixed combination with palonosetron, as NEPA) in CIN prophylaxis is discussed. While the clinical significance of the effect on nausea of the rolapitant–granisetron–dexamethasone combination after cisplatin is not conclusive, rolapitant addition showed no improvement in nausea prophylaxis after AC or moderately emetogenic chemotherapy (MEC). NEPA was superior to palonosetron in the control of nausea after HEC (AC/cisplatin). Moreover, the efficacy of NEPA in nausea control was maintained over multiple cycles of HEC/MEC. Recently, NK₁RAs have been challenged by olanzapine, with olanzapine showing superior efficacy in nausea prevention after HEC. Fixed antiemetic combinations (such as NEPA) or new antiemetics with a long half-life that may be given once per chemotherapy cycle (rolapitant or NEPA) may improve patient compliance with antiemetic treatment.

Management of chemotherapy-induced nausea and vomiting by risk profile: role of netupitant/palonosetron

As recommended by most recent antiemetic guidelines, the optimal prophylaxis of chemotherapy-induced nausea and vomiting (CINV) requires the combination of 5-HT3 receptor antagonist (RA) with an NK1-RA. Moreover, the major predictors of acute and delayed CINV include: young age, female sex, platinum- or anthracycline-based chemotherapy, nondrinker status, emesis in the earlier cycles of chemotherapy, and previous history of motion/morning sickness. Despite improved knowledge of the pathophysiology of CINV and advances in the availability of active antiemetics, an inconsistent compliance with their use has been reported, thereby resulting in suboptimal control of CINV in several cases. In this scenario, a new anti-emetic drug is now available, which seems to be able to guarantee better prophylaxis of CINV and improvement of adherence to guidelines. In fact, netupitant/palonosetron (NEPA) is a ready-to-use single oral capsule, combining an NK1-RA (netupitant) and a 5-HT3-RA (palonosetron), which is to be taken 1 hour before the administration of chemotherapy, ensuring the coverage from CINV for 5 days. We reviewed the role of NEPA in patients at high risk of CINV receiving highly emetogenic chemotherapy. In these patients, NEPA plus dexamethasone, as compared to standard treatments, achieved superior efficacy in all primary and secondary end points during the acute, delayed, and overall phases, including nausea assessment. Moreover, these results were also achieved in female patients receiving anthracycline plus cyclophosphamide-based chemotherapy. NEPA represents a real step forward in the prophylaxis of CINV.

Management of acute and delayed chemotherapy-induced nausea and vomiting: role of netupitant-palonosetron combination

Purpose

The purpose of this review is to summarize and discuss the recently published data (both original studies and reviews) on the oral medication NEPA, consisting of netupitant (a neurokinin-1 receptor antagonist [NK1RA], 300 mg dose) and palonosetron (5-hydroxytryptamine [serotonin or 5HT] type 3 receptor antagonist [5HT₃RA], 0.5 mg dose), in the prevention of the acute and delayed nausea and vomiting in patients receiving highly or moderately emetogenic chemotherapy.

Methods

This review was based on the very limited number of available published trials consisting of two Phase III studies and one Phase II dose-selecting trial.

Results

These studies demonstrated some therapeutic benefits of NEPA over related chemotherapy-induced nausea and vomiting (CINV) prophylaxis management, as well as its beneficial safety profile. In particular, compared with single-dose 0.5 mg palonosetron, the complete response rates for all phases of CINV for the first cycle of highly emetogenic chemotherapy (with cisplatin), as well as anthracycline–cyclophosphamide-based moderately emetogenic chemotherapy, were significantly higher for single-dose NEPA. The high efficacy of NEPA in terms of prevention of CINV continued throughout repeated cycles of highly and moderately emetogenic therapies.

Conclusion

It is currently recommended that patients who are administered highly emetogenic chemotherapy regimens should obtain a three-drug combination consisting of NK1RA, 5HT₃RA, and dexamethasone. The recently available oral combination of NEPA plus dexamethasone provides an additional pharmacological management option that could be considered in this scenario.