Potential of substance P antagonists as antiemetics

Immunohistochemical Identification of Sensory Neuropeptides Calcitonin Gene-Related Peptide, Substance P, and Pituitary Adenylate Cyclase-Activating Polypeptide in Efferent Vestibular Nucleus Neurons

INTRODUCTION

The efferent vestibular system (EVS) originates in brainstem efferent vestibular nuclei (EVN) and modifies afferent vestibular signals at their source, in peripheral vestibular organs. Recent evidence suggests that EVS is also involved in the development of motion sickness symptoms, including vertigo and nausea, but the underlying mechanism is unknown. One possible link between EVN and motion sickness symptoms is through the neuropeptide calcitonin gene-related peptide (CGRP). CGRP often co-exists with substance P and pituitary adenylate cyclase-activating polypeptide (PACAP), two neuropeptides with similar vasodilatory effects. Collectively, these sensory neuropeptides have been associated with vestibular migraine pathophysiology and motion sickness. While CGRP and the fast EVS neurotransmitter, acetylcholine (ACh), have previously been identified in EVN neurons and their peripheral terminals, the presence of substance P and PACAP in the EVN has not yet been described.

METHODS

We used fluorescent immunohistochemistry combined with confocal microscopy to examine the distribution of these three neuropeptides in the mouse EVN. In transgenic choline acetyltransferase (ChAT)-gCaMP6f mice, EVN neurons were positively identified using the fluorescent expression of gCaMP6f. In wild-type C57/BL6 mice, EVN neurons were confirmed using ChAT immunolabelling.

RESULTS

Consistent with previous studies, CGRP was labelled in a subset of cholinergic EVN neurons. Additionally, we also show evidence for substance P and PACAP expression in EVN of transgenic and wild-type mice.

CONCLUSION

The presence of CGRP, substance P, and PACAP in EVN neurons suggests a complex peptidergic modulation of cholinergic signalling, whose release into local blood vessels may contribute to motion sickness symptoms.

Antiemetic effects of sclareol, possibly through 5-HT3 and D2 receptor interaction pathways: In-vivo and in-silico studies

BACKGROUND

Emesis is a complex physiological phenomenon that serves as a defense against numerous toxins, stressful situations, adverse medication responses, chemotherapy, and movement. Nevertheless, preventing emesis during chemotherapy or other situations is a significant issue for researchers. Hence, the majority view contends that successfully combining therapy is the best course of action. In-vivo analysis offers a more comprehensive grasp of how compounds behave within a complex biological environment, whereas in-silico evaluation refers to the use of computational models to forecast biological interactions.

OBJECTIVES

The objectives of the present study were to evaluate the effects of Sclareol (SCL) on copper sulphate-induced emetic chicks and to investigate the combined effects of these compounds using a conventional co-treatment approach and in-silico study.

METHODS

SCL (5, 10, and 15 mg/kg) administered orally with or without pre-treatment with anti-emetic drugs (Ondansetron (ODN): 24 mg/kg, Domperidone (DOM): 80 mg/kg, Hyoscine butylbromide (HYS): 100 mg/kg, and Promethazine hydrochloride (PRO): 100 mg/kg) to illustrate the effects and the potential involvement with 5HT3, D2, M3/AChM, H1, or NK1 receptors by SCL. Furthermore, an in-silico analysis was conducted to forecast the role of these receptors in the emetic process.

RESULTS

The results suggest that SCL exerted a dose-dependent anti-emetic effect on the chicks. Pretreatment with SCL-10 significantly minimized the number of retches and lengthened the emesis tendency of the experimental animals. SCL-10 significantly increased the anti-emetic effects of ODN and DOM. However, compared to the ODN-treated group, (SCL-10 + ODN) group considerably (p < 0.0001) extended the latency duration (109.40 ± 1.03 s) and significantly (p < 0.01) decreased the number of retches (20.00 ± 0.70), indicating an anti-emetic effect on the test animals. In in-silico analysis, SCL exhibited promising binding affinities with suggesting receptors.

CONCLUSION

SCL-10 exerted an inhibitory-like effect on emetic chicks, probably through the interaction of the 5HT3 and D2 receptors. Further studies are highly appreciated to validate this study and determine the precise mechanism(s) behind the anti-emetic effects of SCL. We expect that SCL-10 may be utilized as an antiemetic treatment in a single dosage form or that it may function as a synergist with other traditional medicines.

A re-consideration of neural/receptor mechanisms in chemotherapy-induced nausea and vomiting: current scenario and future perspective

The neural mechanisms and the receptors behind the course of chemotherapy-induced nausea and vomiting (CINV) are well described and considered mechanistically multifactorial, whereas the neurobiology of nausea is not completely understood yet. Some of the anti-neoplastic medications like cisplatin result in biphasic vomiting response. The acute phase of vomiting is triggered mainly via the release of serotonin from the enterochromaffin (EC) cells in the gastrointestinal tract (GIT) and results in stimulation of dorsal vagal complex (DVC) of the vomiting center and the vomiting is initiated by downward communication to the gut via vagal efferents. Agonism of 5HT3 receptors is majorly involved in the mediation of the acute phase. Therefore, antagonists at 5HT3 receptors are effective in the management of acute-phase vomiting episodes. Likewise, Dopamine type 2 (D2) receptors, dopamine neurotransmitter, Muscarinic receptors (M3), GLP1 receptors, and histaminergic receptors (H1) are also implicated in the vomiting act as well. In continuation, Cannabinoid type 1 (CB1) receptors are also recommended and included in the guidelines as agonism of presynaptically located CB1 receptors inhibits the release of excitatory neurotransmitters responsible for vomiting initiation. The delayed phase involves the release of "Substance P" in the gut and results in the stimulation of neurokinin-1 (NK1) receptors centrally in the area postrema (AP) and nucleus tractus solitarius (NTS), subsequently the vomiting response. The current understanding is the existence of overlapping mechanisms of neurotransmitters, serotonin, dopamine, and substance P throughout the time course of CINV. Furthermore, the emetic neurotransmitters are released via calcium ion (Ca++)-dependent mechanisms, implicating the molecular targets of intracellular Ca++ signaling in emetic circuitry. The current review entails the neurobiology of nausea and vomiting induced by cancer chemotherapeutic agents and the recent approaches in the management.

Pharmacokinetics of maropitant citrate in Rhode Island Red chickens (Gallus gallus domesticus) following subcutaneous administration

Maropitant citrate is a synthetic neurokinin‐1 receptor antagonist and substance P inhibitor used for control of emesis in dogs in cats. Maropitant citrate is used empirically in birds, despite a lack of pharmacokinetic data in avian species. The objective of this study was to determine the pharmacokinetic profile of a single dose of maropitant citrate 1 and 2 mg/kg subcutaneously (SC) in eight Rhode Island Red hens (Gallus gallus domesticus). A crossover study design was used with 1‐week washout between trials. Blood samples were collected over 36 h after drug administration. Plasma concentrations were measured using liquid chromatography–tandem mass spectrometry and pharmacokinetic parameters were determined via non‐compartmental analysis. The mean maximum plasma concentration, time to maximum concentration, and elimination half‐life following 1 and 2 mg/kg SC were 915.6 ± 312.8 ng/ml and 1195.2 ± 320.2 ng/ml, 0.49 ± 0.21 h and 1.6 ± 2.6 h, and 8.47 ± 2.24 h and 8.58 ± 2.6 h, respectively. Pharmacokinetic data suggests doses of 1 or 2 mg/kg SC may be administered every 12–24 h to maintain above target plasma concentration similar to dogs (90 ng/ml). These data provide a basis for further investigation of maropitant citrate pharmacokinetics and pharmacodynamics in birds.

A Substance P (SP)/Neurokinin-1 Receptor Axis Promotes Perineural Invasion of Pancreatic Cancer and Is Affected by lncRNA LOC389641

Perineural invasion (PNI) is considered to be a main reason for the poor prognosis of pancreatic cancer. In the present study, we analyzed the roles of substance P (SP)/neurokinin-1 receptor (NK-1R) and lncRNA LOC389641 in pancreatic cancer PNI. Pancreatic cancer cell lines BxPC-3 and MIAPaCa-2 were cocultured with SH-SY5Y cells and then stimulated with SP to simulate the in vivo influence of ganglia on pancreatic cancer. The BxPC-3 and MIAPaCa-2 cells were transfected with a neurokinin-1 receptor (NK-1R) overexpression vector, NK-1R silencing vector, LOC389641 overexpression vector, or LOC389641 silencing vector, respectively. The proliferative abilities of BxPC-3 and MIAPaCa-2 cells were assessed using the cell counting kit-8 and 5-ethynyl-2'-deoxyuridine (EdU) assays. Wound-healing and Transwell assays were performed to determine the migration and invasion abilities of the cells. When SP was added to the coculture system, it positively regulated cancer cell proliferation, migration, and PNI and significantly activated the NK-1R/Akt/NF-κB signaling pathway. Incubation with 100 nmol/L SP for 24 h was selected as the optimal condition for treatment. The activated NK-1R positively regulated the proliferation, migration, and invasion of pancreatic cancer cells. However, the levels of lncRNA LOC389641 and tumor necrosis factor receptor SF10A (TNFRSF10A) mRNA in BxPC-3 and MIAPaCa-2 cells were not affected by SP treatment. Overexpression or silencing of LOC389641 changed the effect of SP stimulation on pancreatic cancer PNI. When taken together, these results revealed that SP/NK-1R and LOC389641 promoted the progression of pancreatic cancer PNI. Moreover, we found that pancreatic cancer PNI promoted by the SP/NK-1R axis could be blocked by the TNFRSF10A/NF-κB pathway mediated by LOC389641.

The Rise of SARS-CoV-2 Variants and the Role of Convalescent Plasma Therapy for Management of Infections

Novel therapies for the treatment of COVID-19 are continuing to emerge as the SARS-Cov-2 pandemic progresses. PCR remains the standard benchmark for initial diagnosis of COVID-19 infection, while advances in immunological profiling are guiding clinical treatment. The SARS-Cov-2 virus has undergone multiple mutations since its emergence in 2019, resulting in changes in virulence that have impacted on disease severity globally. The emergence of more virulent variants of SARS-Cov-2 remains challenging for effective disease control during this pandemic. Major variants identified to date include B.1.1.7, B.1.351; P.1; B.1.617.2; B.1.427; P.2; P.3; B.1.525; and C.37. Globally, large unvaccinated populations increase the risk of more and more variants arising. With successive waves of COVID-19 emerging, strategies that mitigate against community transmission need to be implemented, including increased vaccination coverage. For treatment, convalescent plasma therapy, successfully deployed during recent Ebola outbreaks and for H1N1 influenza, can increase survival rates and improve host responses to viral challenge. Convalescent plasma is rich with cytokines (IL-1β, IL-2, IL-6, IL-17, and IL-8), CCL2, and TNFα, neutralizing antibodies, and clotting factors essential for the management of SARS-CoV-2 infection. Clinical trials can inform and guide treatment policy, leading to mainstream adoption of convalescent therapy. This review examines the limited number of clinical trials published, to date that have deployed this therapy and explores clinical trials in progress for the treatment of COVID-19.

Evaluation of analgesic interaction between morphine, maropitant and dexmedetomidine in dogs undergoing ovariohysterectomy

ABSTRACTAims: To compare the analgesic effect of morphine combined with maropitant and/or dexmedetomidine to morphine alone but at a higher dose, and to evaluate the pharmacokinetics of the drug combinations, in dogs undergoing ovariohysterectomy (OHE).Methods: Forty client-owned dogs were randomised into four treatment groups (n = 10 per group) each to receive a different analgesic protocol. After premedication with I/M acepromazine, anaesthesia was induced with propofol to effect and maintained with isoflurane in 100% oxygen delivered via a circle system. The heart rate, respiratory rate, blood pressure, haemoglobin oxygen saturation, end-tidal partial pressure of carbon dioxide, electrocardiogram and rectal temperature were monitored during anaesthesia. The test drugs (Mor: 0.6 mg/kg morphine; Maro + Mor: 0.3 mg/kg morphine and 1 mg/kg maropitant; Dex + Mor: 0.3 mg/kg morphine and 10 μg/kg dexmedetomidine; Dex + Maro + Mor: 0.2 mg/kg morphine, 7 μg/kg dexmedetomidine and 0.7 mg/kg maropitant) were administered I/M after induction of anaesthesia and 30 minutes before the expected start time of ovariohysterectomy, which was carried out by veterinary students under veterinary supervision. The short form of the Glasgow composite measure pain scale (CMPS-SF) and visual analogue scale (VAS) were used for pain assessment at 15 and 30 minutes and 1, 2, 3, 6, 9 and 24 hours after extubation. Dogs with CMPS-SF pain score ≥ 6 received rescue analgesia with S/C buprenorphine (0.02 mg/kg). Blood samples were collected before, 15, 30, 60 and 120 minutes after injection of the test drugs and concentration of the test drugs in plasma was determined by liquid chromatography-mass spectrometry.Results: Dogs that received Dex + Mor had significantly lower CMPS-SF (estimate of difference = -1.53 (SE 0.58); p = 0.010) and VAS (estimate of difference = -0.67 (SE 0.25); p = 0.007) scores compared to the dogs that received morphine alone. There was no evidence of a difference in the number of dogs requiring rescue between groups. All dogs that received dexmedetomidine showed cardiac arrhythmia and second-degree heart block. Mean (SD) maximum concentrations (C_max,) of morphine in plasma were 6.8 (4.56), 9.56 (8.29), 9.30 (3.35) and 18.99 (9.41) ng/mL for the groups Dex + Mor, Dex + Maro + Mor, Maro + Mor and Mor respectively. The C_max of morphine was significantly lower in the Dex + Mor (p = 0.004), Dex + Maro + Mor (p = 0.034) and Maro + Mor (p = 0.018) groups compared to the Mor group.Conclusions For dogs undergoing ovariohysterectomy, lower doses of morphine (0.2 and 0.3 mg/kg) combined with dexmedetomidine or maropitant may provide analgesia equivalent to or better than morphine when given alone at a higher dose (0.6 mg/kg).Abbreviations: AUC: Area under curve; C_max: Maximum concentration in plasma; CMPS-SF: Glasgow composite measure pain scale - short form; NK1: Neurokinin-1; OHE: Ovariohysterectomy; T_max: Time to C_max; T_1/2: Half-life of terminal elimination phase; VAS: Visual analogue scale.

Elevated serum substance P level as a predictive marker for moderately emetogenic chemotherapy-induced nausea and vomiting: A prospective cohort study

Chemotherapy‐induced nausea and vomiting (CINV) is an unbearable side effect. Identifying high emetic risk patients and providing more active antiemetics strategies are mandatory to improve the tolerability of chemotherapy. In this prospective cohort study, leptin, ghrelin, and substance P were measured at baseline, day 3, and day 14 during the first cycle of chemotherapy. Nausea and vomiting were measured each day for the first 4 days of the first cycle of chemotherapy. Eighty‐two patients were enrolled. Colorectal cancer (61%) and gastric cancer (35.4%) were common cancer types. All patients received moderate emetic risk chemotherapy. Forty‐five (54.9%) patients had nausea, and 15 (18.3%) patients experienced vomiting. In univariate analysis, a higher level of baseline substance P, which is a target of NK1‐RA (Neurokinin 1 receptor antagonist), was a significant predictive marker for chemotherapy‐induced nausea [odds ratio (OR): 2.6, 95% confidence interval (CI): 1.02–6.62, p = 0.046]. Regarding chemotherapy‐induced vomiting, patients with higher levels of substance P had a greater chance of vomiting [OR: 1.72, 95% CI: 0.49–5.99, p = 0.395] than those with lower levels of substance P. In patients receiving moderate emetic risk chemotherapy, active antiemetics, including NK1‐RA, could be considered for those with high levels of substance P.

Asymmetric Hydrogenation of 2-Aryl-3-phthalimidopyridinium Salts: Synthesis of Piperidine Derivatives with Two Contiguous Stereocenters

Asymmetric hydrogenation of 2-aryl-3-phthalimidopyridinium salts catalyzed by the Ir/SegPhos catalytic system was described, leading to the corresponding chiral piperidine derivatives bearing two contiguous chiral centers, with high levels of enantioselectivities and diastereoselectivities. A gram-scale experiment has demonstrated the utility of this approach. The phthaloyl group could be easily removed and then smoothly converted to key intermediate (+)-CP-99994 as one of the neurokinin 1 receptor antagonists.

Effect of combinations of morphine, dexmedetomidine and maropitant on the electroencephalogram in response to acute electrical stimulation in anaesthetized dogs

This study was conducted to compare the efficacy of combinations of morphine, dexmedetomidine and maropitant in preventing the changes in electroencephalographic (EEG) indices of nociception in anaesthetized dogs subjected to a noxious electrical stimulus. In a crossover study, eight healthy adult dogs were randomly allocated to four groups: Mor: morphine 0.6 mg/kg; Dex + Mor: morphine 0.3 mg/kg + dexmedetomidine 5 μg/kg; Maro + Mor: morphine 0.3 mg/kg + maropitant 1 mg/kg; and Dex + Maro + Mor: morphine 0.2 mg/kg + dexmedetomidine 3 μg/kg + maropitant 0.7 mg/kg. Following intramuscular administration of test drugs in a minimal anaesthesia model, a supramaximal electrical stimulus (50 V at 50 Hz for 2 s) was applied and the EEG data were recorded. There were significant increases (p < .05) in the poststimulus median frequency (F50) only in groups Mor and Maro + Mor. Dex + Mor group had a significantly lower change in F50 and F95 compared to all other treatment groups. There was no correlation of the changes in EEG frequencies with blood plasma concentration of the drugs during and after noxious stimulation. Combination of dexmedetomidine and morphine was most effective in abolishing the changes in EEG indices in response to a noxious stimulus indicating a supra-additive interaction between these two drugs.

New insight into the role of substance P/neurokinin-1 receptor system in breast cancer progression and its crosstalk with microRNAs

The neuropeptide substance P (SP) triggers a variety of tumor-promoting signaling pathways through the activation of neurokinin-1receptor (NK1R), a class of neurokinin G protein-coupled receptors superfamily. Recent researches in our and other laboratories have shown the overexpression of both SP and NK1R in breast cancer (BC) patients. SP/NK1R signaling is strongly implicated in the pathogenesis of BC through affecting cell proliferation, migration, metastasis, angiogenesis, and resistance. Therefore, SP/NK1R signaling responses must be rigorously regulated; otherwise, they would contribute to a more aggressive BC phenotype. Recently, microRNAs (miRNAs) as a specific class of epigenetic regulators have been shown to regulate NK1R and thus, controlling SP/NK1R signaling responses in BC. This review summarizes the current knowledge of the role of SP/NK1R signaling and its therapeutic potentials in BC. We also provide an overview regarding the effects of miRNA-mediated NK1R regulatory mechanisms in controlling BC tumorigenesis to gain a clearer view and thus better management of cancer.

Pharmacokinetics of morphine in combination with dexmedetomidine and maropitant following intramuscular injection in dogs anaesthetized with halothane

The purpose of this study was to evaluate the pharmacokinetics of morphine in combination with dexmedetomidine and maropitant injected intramuscularly in dogs under general anaesthesia. Eight healthy dogs weighing 25.76 ± 3.16 kg and 3.87 ± 1.64 years of age were used in a crossover study. Dogs were randomly allocated to four groups: (1) morphine 0.6 mg/kg; (2) morphine 0.3 mg/kg + dexmedetomidine 5 μg/kg; (3) morphine 0.3 mg/kg + maropitant 1 mg/kg; (4) morphine 0.2 mg/kg + dexmedetomidine 3 μg/kg + maropitant 0.7 mg/kg. Blood samples were collected before, 15 and 30 min, and 1, 2, 3 4, 6 and 8 hr after injection of the test drugs. Plasma concentration of the drugs was determined by liquid chromatography-mass spectrometry. The elimination half-life (T_1/2 ) of morphine was higher and the clearance rate (CL) was lower when combined with dexmedetomidine (T_1/2  = 77.72 ± 20.27 min, CL = 119.41 ± 23.34 ml kg^-1  min^-1 ) compared to maropitant (T_1/2  = 52.73 min ± 13.823 ml kg^-1  min^-1 , CL = 178.57 ± 70.55) or morphine alone at higher doses (T_1/2  = 50.53 ± 12.55 min, CL = 187.24 ± 34.45 ml kg^-1  min^-1 ). Combining morphine with dexmedetomidine may increase the dosing interval of morphine and may have a clinical advantage.

The safety of rolapitant for the treatment of nausea and vomiting associated with chemotherapy

Introduction: Chemotherapy-induced nausea and vomiting is a significant clinical issue that affects patients' quality of life as well as treatment decisions. Significant improvements in the control of chemotherapy-induced nausea and vomiting have occurred in the past 15 years with the introduction of new antiemetic agents 5-HT3, receptor antagonists, neurokinin-1 receptor antagonists, and olanzapine. Oral (aprepitant, 2003; netupitant, 2014; rolapitant, 2015) neurokinin-1 receptor antagonists have been developed along with intravenous formulations (fosaprepitant, NEPA, rolapitant, HTX-019) for the prevention of chemotherapy-induced nausea and vomiting.Areas covered: This review presents a description of the safety and efficacy of rolapitant along with a comparison to the other oral and intravenous formulations of the neurokinin-1 receptor antagonists.Expert opinion: Oral rolapitant has been demonstrated in clinical trials to be safe and effective in controlling chemotherapy-induced nausea and vomiting in patients receiving moderately and highly emetogenic chemotherapy. Rolapitant has a longer half-life (180 h) than other commercially available NK-1 receptor antagonists and does not induce or inhibit CYP34A, unlike the other NK-1 receptor antagonists. Future studies may determine if these may be important clinical issues.

Do we still need to study palonosetron for chemotherapy-induced nausea and vomiting? A cumulative meta-analysis

INTRODUCTION

The aim is to conduct an updated systematic review comparing palonosetron to other 5-HT₃RAs for the prophylaxis of CINV, assess for publication biases, and determine whether further RCTs are required, that could potentially lead to a different meta-conclusion.

METHODS

Random-effects analysis model was used to generate odds ratio (OR), risk differences (RD) and accompanying 95% confidence intervals (CI). Funnel plots to assess for biases and cumulative meta-analyses to assess effect size over time were generated.

RESULTS

4145 patients were randomized to palonosetron and 4911 received other 5-HT₃RAs. In the majority of efficacy endpoints, the meta-conclusion has not changed over time - recent clinical trials simply narrow CIs the meta-conclusion. Safety profile boasts a stable conclusion over time. No publication biases exist.

CONCLUSION

Considering the vast amount of resources needed to conduct RCTs, resources should be dedicated to other prophylactic treatments/settings which have not been as well explored.

Should palonosetron be a preferred 5-HT3 receptor antagonist for chemotherapy-induced nausea and vomiting? An updated systematic review and meta-analysis

PURPOSE

Chemotherapy-induced nausea and vomiting (CINV) continues to be a common side effect of systemic anticancer therapy, decreasing quality of life and increasing resource utilization. The aim of this meta-analysis was to investigate the comparative efficacy and safety of palonosetron relative to other 5-HT₃RAs.

METHODS

A literature search was carried out in Ovid MEDLINE, Embase, and Cochrane Central Register of Controlled Trials. Full-text references were then screened and included in this meta-analysis if they were an RCT and had adequate data regarding one of the five primary endpoints-complete response (CR), complete control (CC), no emesis, no nausea, or no rescue medications.

RESULTS

A total of 24 RCTs were included in this review. Palonosetron was statistically superior to other 5-HT₃RAs for 10 of the 19 assessed endpoints. Only one endpoint-emesis in the overall phase-had noticeable more favorable data for palonosetron to the point that it approached the 10% risk difference (RD) threshold as specified by the MASCC/ESMO antiemetic panel; another two endpoints (CR in the overall phase and nausea in the delayed phase) approached the 10% threshold.

CONCLUSIONS

Palonosetron seems to be more efficacious and safe than other 5-HT₃RAs-statistically superior in 10 of 19 endpoints. It is, however, only clinically significant in one endpoint and approached clinically significant difference in another two endpoints. Within the limits of this meta-analysis, our results indicate that palonosetron may not be as superior in efficacy and safety as reported in a previous meta-analysis, and supports the recent MASCC/ESMO, ASCO, and NCCN guidelines in not generally indicating palonosetron as the 5-HT₃RA of choice.

Assessment of pre-operative maropitant citrate use in macaque (Macaca fasicularis & Macaca mulatta) neurosurgical procedures

BACKGROUND

Retrospective analysis of post-operative vomiting (POV) in non-human primates at our institution was 11%. Based on this additional risk factor for post-operative complications, we aimed to eliminate or decrease POV by adding an antiemetic, maropitant citrate, to the pre-medication protocol.

METHODS

Retrospective and prospective data were collected over a 5-year period from 46 macaques of two species during 155 procedures. Additionally, blood was collected from five Macaca mulatta to perform a pharmacokinetic analysis.

RESULTS

A 1 mg/kg subcutaneous dose of maropitant given pre-operatively significantly decreased POV. Findings indicated post-neurosurgical emesis in Macaca fasicularis was significantly greater than in Macaca mulatta. Pharmacokinetic analysis of maropitant in Macaca mulatta determined the mean maximum plasma concentration to be 113 ng/mL.

CONCLUSIONS

Maropitant administration prior to anesthesia for neurosurgeries decreased our incidence of POV to 1%. The plasma concentration reaches the proposed plasma level for clinical efficacy approximately 20 minutes after administration.

Suppression of Cisplatin-Induced Vomiting by Cannabis sativa in Pigeons: Neurochemical Evidences

Cannabis sativa (CS, family Cannabinaceae) has been reported for its anti-emetic activity against cancer chemotherapy-induced emesis in animal models and in clinics. The current study was designed to investigate CS for potential effectiveness to attenuate cisplatin-induced vomiting in healthy pigeons and to study the impact on neurotransmitters involved centrally and peripherally in the act of vomiting. High-performance liquid chromatography system coupled with electrochemical detector was used for the quantification of neurotransmitters 5-hydroxytryptamine (5HT), dopamine (DA) and their metabolites; Di-hydroxy Phenyl Acetic acid (Dopac), Homovanillic acid (HVA), and 5-hydroxy indole acetic acid (5HIAA) centrally in specific brain areas (area postrema and brain stem) while, peripherally in small intestine. Cisplatin (7 mg/kg i.v.) induce emesis without lethality across the 24 h observation period. CS hexane fraction (CS-HexFr; 10 mg/kg) attenuated cisplatin-induced emesis ∼ 65.85% (P < 0.05); the reference anti-emetic drug, metoclopramide (MCP; 30 mg/kg), produced ∼43.90% reduction (P < 0.05). At acute time point (3^rd h), CS-HexFr decreased (P < 0.001) the concentration of 5HT and 5HIAA in the area postrema, brain stem and intestine, while at 18^th h (delayed time point) CS-HexFr attenuated (P < 0.001) the upsurge of 5HT caused by cisplatin in the brain stem and intestine and dopamine in the area postrema. CS-HexFr treatment alone did not alter the basal neurotransmitters and their metabolites in the brain areas and intestine except 5HIAA and HVA, which were decreased significantly. In conclusion the anti-emetic effect of CS-HexFr is mediated by anti-serotonergic and anti-dopaminergic components in a blended manner at the two different time points, i.e., 3^rd and 18^th h in pigeons.

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.

Gastroparesis: Medical and Therapeutic Advances

Gastroparesis is a chronic, bothersome, and often disabling neuromuscular disorder of the upper gastrointestinal tract. The most frequently reported symptoms of gastroparesis include nausea, vomiting, epigastric pain, early satiety, and unintentional weight loss. Etiologies of gastroparesis include diabetes, connective tissue disorders, prior infection, mesenteric ischemia, and post-surgical complications. The largest category of gastroparesis patients is comprised of those in whom no definitive cause can be identified (idiopathic gastroparesis). The individual and societal burden of gastroparesis is substantial. It considerably reduces patients' quality of life accompanied by a significant negative impact to the healthcare system. The current treatments of gastroparesis are less than ideal. Dietary modification may improve symptoms in patients with mild disease. Metoclopramide is the only medication currently approved for the treatment of gastroparesis; however, it is associated with adverse effects in a sizable proportion of patients. Other medications are frequently employed to treat symptoms of nausea and vomiting, although technically all are used off-label since they are not FDA approved for the treatment of gastroparesis. These data highlight the need to identify novel, more effective treatment options for this disabling disease. This review will provide a brief synopsis on the epidemiology, etiology, and impact of gastroparesis, discussing new therapeutic advances.

This CE is published through an unrestricted educational grant from Bristol-Myers Squibb

Credit

This lesson is good for 0.2 CE units, with a passing grade of 70%.

Goal

The goal of this program is to inform the participant of costeffective ways to prevent, identify, and manage nausea and vomiting induced by antineoplastic agents.

Objectives

At the completion of this program the participant will be able to: 1. List antineoplastic agents associated with a high incidence of nausea and vomiting. 2. Identify patient-specific risk factors for developing chemotherapyinduced nausea and vomiting (CINV) and how these factors may influence treatment of this syndrome. 3. Compare the three major types of CINV, including the pathophysiologic mechanism, time of onset, and symptom duration of each type. 4. Explain the mechanism of action and appropriate place in therapy for each type of antiemetic agent. 5. Differentiate between pharmacologic regimens for the prevention and treatment of CINV in adults. 6. Identify drug-specific factors that must be considered in developing a formulary management strategy for the antiemetic agents. 7. Describe specific information that the pharmacist can share with patients to help them understand and manage CINV.

5-Hydroxyindoleacetic acid and substance P profiles in patients receiving emetogenic chemotherapy

Background. Even though direct cause and effect has not been proved, clinical evidence suggests serotonin and substance P (SP) are involved in the emetic response following chemotherapy. Because of several parallels, we hypothesized that SP release, like serotonin, may be propagated by chemotherapy and both substances can be measured in biological fluids, and correlated with a particular phase of emesis.

Methods. Urinary 5-hydroxyindoleacetic acid (5-HIAA) was assessed by HPLC; serum and urine SP were measured by immunoassay. In addition to construction of neurotransmitter profiles, all SP data were grouped according to cisplatin dosages, = or>75 mg/m 2 versus <75 mg/m2, and phase of emesis, acute versus delayed. Analyses of these data were performed by repeated measures analysis of variance.

Results. Samples were collected over a 72-hour period from 26 adult patients who received cisplatin-( n=13) or non-cisplatin-containing ( n=13) chemotherapy. Mean baseline 5-HIAA: creatinine ratios were 5.23 and 5.16 in females and males, respectively; mean baseline SP levels were 392 and 181 pg/mL in females and males, respectively. Comparisons between SP data stratified by cisplatin dosage and emetic phase were significantly different, P <0.0001.

Conclusions. Laboratory studies provide additional evidence that serotonin and SP are involved primarily, though not exclusively, in acute and delayed vomiting, respectively.

Plasma substance P concentrations in patients undergoing general anesthesia: an objective marker associated with postoperative nausea and vomiting

Background

This study investigated plasma concentrations of substance P (SP) in patients undergoing general anesthesia (GA) and postoperative nausea and vomiting (PONV). This prospective, observational, cohort study included 23 patients who underwent scheduled surgery under general anesthesia. Blood was collected from the radial artery at predetermined time points (15-30 mins prior anesthesia, 15-30 mins after surgery/GA, and 24 h after surgery). PONV, SP concentrations, risk factors, and analgesics used were measured.

Findings

Nine of 23 patients experienced PONV. In patients without PONV, SP concentrations significantly decreased (P < 0.0001) at the end of surgery/GA, compared to baseline, and recovered at 24 h after surgery/GA (452.9 ± 146.2 vs. 666.9 ± 176.5 vs. 580.7 ± 168.6 pg/mL, respectively), whereas SP levels were unchanged during surgery/GA and increased at 24 hours after surgery (P = 0.020) in patients with PONV (726.1 ± 167.8 vs. 655.8 ± 168.0 vs. 779.7 ± 220.7 pg/mL, respectively).

Conclusions

These finding suggest that SP levels may be utilized as an objective marker for PONV.

Rolapitant for the treatment of chemotherapy-induced nausea and vomiting

Chemotherapy-induced nausea and vomiting is a significant clinical issue which affects patient's quality of life and treatment decisions. Significant improvements in the control of chemotherapy-induced nausea and vomiting have occurred in the past 15 years with the introduction of new antiemetic agents 5-HT3, receptor antagonists, neurokinin-1 (NK-1) receptor antagonists, and olanzapine. Aprepitant was the first NK-1 receptor antagonist introduced (2003) for the prevention of chemotherapy-induced nausea and vomiting in combination with a 5-HT3 receptor antagonist and dexamethasone. A second NK-1 receptor antagonist netupitant was approved for use in October 2014. Phase III clinical trials of an additional NK-1 receptor antagonist rolapitant have been completed, and the data have been submitted for regulatory approval. A description of rolapitant and its role in chemotherapy-induced nausea and vomiting will be presented, along with a comparison of the other neurolinin-1 receptor antagonists aprepitant and netupitant.

Management of Chemotherapy Induced Nausea and Vomiting in Patients on Multiday Cisplatin Based Combination Chemotherapy

Introduction of cisplatin based chemotherapy has revolutionized the treatment of germ cell tumors. A common side effect of multiday cisplatin chemotherapy is severe nausea and vomiting. Considerable progress has been made in the control of these side effects since the introduction of cisplatin based chemotherapy in the 1970s. Germ cell tumor which is a model for a curable neoplasm has also turned into an excellent testing ground to develop effective strategies to prevent chemotherapy induced nausea and vomiting (CINV) in multiday cisplatin based regimens. The use of combination of a 5-hydroxytryptamine (HT)3 receptor antagonist, a neurokinin-1 (NK1) antagonist, and dexamethasone has greatly improved our ability to prevent and control acute and delayed CINV. Mechanism and pattern of CINV with multiday chemotherapy may differ from those in single day chemotherapy and therefore efficacy of antiemetic drugs as observed in single day chemotherapy may not be applicable. There are only few randomized clinical trials with special emphasis on multiday chemotherapy. Further studies are essential to determine the efficacy, optimal dose, and duration of the newer agents and combinations in multiday cisplatin based chemotherapy.

Palonosetron with aprepitant plus dexamethasone to prevent chemotherapy-induced nausea and vomiting during gemcitabine/cisplatin in urothelial cancer patients

OBJECTIVES

To evaluate the appearance of chemotherapy-induced nausea and vomiting, and to compare the antiemetic efficacy of the triple combination of palonosetron, aprepitant and dexamethasone with that of our old regimen using first-generation 5-hydroxytryptamine 3-receptor antagonists and dexamethasone during gemcitabine and cisplatin chemotherapy in patients with advanced urothelial cancer.

METHODS

We carried out a multi-institutional study including 122 patients who received gemcitabine and cisplatin for advanced urothelial cancer between February 2005 and January 2012. Uncontrolled chemotherapy-induced nausea and vomiting events were identified through records of nausea and vomiting, additional infusion, rescue medications, and/or records of food intake.

RESULTS

First-generation 5-hydroxytryptamine 3-receptor antagonists (ondansetron or granisetron) plus dexamethasone were used for 75 patients (cohort 1), and palonosetron with dexamethasone plus aprepitant for 47 patients (cohort 2). Patients in cohort 2 had significantly higher complete response (defined as no emetic episodes and no rescue medication use) rates than those in cohort 1 during the overall phase in the first cycle (85.7% vs 65.3%, P = 0.012), and all cycles (78.7% vs 50.7%, P = 0.0019) of gemcitabine and cisplatin. Patients in cohort 2 were more likely to achieve more favorable chemotherapy-induced nausea and vomiting control; that is, a lower grade of nausea, vomiting or anorexia, lower incidence of rescue therapy required, and shorter time to become chemotherapy-induced nausea- and vomiting-free than patients in cohort 1.

CONCLUSIONS

The present results show that palonosetron in combination with aprepitant and dexamethasone is more effective to prevent chemotherapy-induced nausea and vomiting in urothelial cancer patients treated with gemcitabine and cisplatin than first-generation 5-hydroxytryptamine 3-receptor antagonists plus dexamethasone.

Anti-emetic mechanisms of Zingiber officinale against cisplatin induced emesis in the pigeon; behavioral and neurochemical correlates

BACKGROUND

Zingiber officinale (ZO, family Zingiberaceae) has been reported for its antiemetic activity against cancer chemotherapy induced emesis in animal models and in clinics. Current study was designed to investigate ZO for potential usefulness against cisplatin induced vomiting in pigeon and its effects on central and peripheral neurotransmitters involved in the act of vomiting.

METHODS

Zingiber officinale acetone fraction (ZO-ActFr) was investigated for attenuation of emesis induced by cisplatin in healthy pigeons. Neurotransmitters DA, 5HT and their metabolites DOPAC, HVA and 5HIAA were analyzed using High Performance Liquid Chromatography system coupled with electrochemical detector in area postrema, brain stem and intestine. Antiemetic effect of ZO-ActFr was correlated with central and intestinal neurotransmitters levels in pigeon.

RESULTS

Cisplatin (7 mg/kg i.v.) induced emesis without lethality upto the observation period. ZO-ActFr (25, 50 & 100 mg/kg) attenuated cisplatin induced emesis ~ 44.18%, 58.13% (P < 0.05) and 27.9%, respectively; the reference drug, metoclopramide (MCP; 30 mg/kg), produced ~ 48.83% reduction (P < 0.05). ZO-ActFr reduced (P < 0.05 - 0.001) 5-hydroxytryptamine (5HT) concentration in the area postrema, brain stem and intestine at 3(rd) hour of cisplatin administration, while at the 18(th) hour ZO treatments attenuated the dopamine upsurge (P < 0.001) caused by cisplatin in the area postrema and 5HT concentration (P < 0.01 - 0.001) in the brain stem and intestine. ZO treatments alone did not altered the basal neurotransmitters and their metabolites in the brain areas and intestine.

CONCLUSION

The behavioral study verify the antiemetic profile of ZO against cisplatin induced emesis in the pigeon, where central and peripheral neural evidences advocate the involvement of serotonergic mechanism at initial time point (3(rd) hr), while the later time point (18(th) hr) is associated with serotonergic and dopaminergic component in the mediation of its antiemetic effect.

Profile of netupitant/palonosetron (NEPA) fixed dose combination and its potential in the treatment of chemotherapy-induced nausea and vomiting (CINV)

Chemotherapy-induced nausea and vomiting (CINV) is associated with a significant deterioration in quality of life. The emetogenicity of the chemotherapeutic agents, repeated chemotherapy cycles, and patient risk factors significantly influence CINV. The use of a combination of a 5-hydroxytryptamine-3 (5-HT3) receptor antagonists, dexamethasone, and a neurokinin-1 (NK-1) receptor antagonist has significantly improved the control of acute and delayed emesis in single-day chemotherapy. Palonosetron, a second generation 5-HT3 receptor antagonist with a different half-life, different binding capacity, and a different mechanism of action than the first generation 5-HT3 receptor antagonists, appears to be the most effective agent in its class. Netupitant, is a new NK-1 receptor antagonist with a high binding affinity, a long half-life of 90 hours, is metabolized by CYP3A4, and is an inhibitor of CYP3A4. NEPA is an oral fixed-dose combination of netupitant and palonosetron which has recently been employed in Phase II and Phase III clinical trials for the prevention of CINV in patients receiving moderately and highly emetogenic chemotherapy (MEC and HEC). The clinical trials demonstrated that NEPA (300 mg of netupitant plus 0.50 mg of palonosetron) significantly improved the prevention of CINV compared to the use of palonosetron alone in patients receiving either HEC or MEC. The clinical efficacy was maintained over multiple cycles of chemotherapy. NEPA (Akynzeo(®)) has recently been approved by the Food and Drug Administration (FDA) to treat nausea and vomiting in patients undergoing cancer chemotherapy.

Addition of aprepitant improves protection against cisplatin-induced emesis when a conventional anti-emetic regimen fails

OBJECTIVE

We investigated whether aprepitant, a neurokinin-1 antagonist, could decrease chemotherapy-induced nausea and vomiting (CINV) following cisplatin, when a conventional anti-emetic regimen had failed.

METHODS

This was a prospective study (April 2011-April 2012) of patients with lung cancer, treated with cisplatin at the Beijing Cancer Hospital, and initially receiving granisetron, dexamethasone, and metoclopramide as anti-emetics. If patients experienced vomiting of grade ≥2 and required rescue anti-emetic medications during the first cycle, oral aprepitant was added in subsequent cycles (day 1: 125 mg; days 2-3: 80 mg once daily). Acute (day 1) and delayed (days 2-5) nausea and vomiting, use of rescue medications, and occurrence of adverse reactions were monitored after the start of chemotherapy.

RESULTS

Twenty-five of 132 patients (18.9 %) were administered aprepitant for secondary prophylaxis against emesis during the second cycle of chemotherapy. The incidences of acute and delayed nausea were 52 and 100 % in the first cycle, but 8 and 72 % in the second cycle. The incidences of acute and delayed vomiting were 20 and 100 % in the first cycle, but 0 and 36 % in the second cycle. No patients required rescue medications or intravenous rehydration during the second cycle. Aprepitant was not associated with additional adverse events.

CONCLUSIONS

In patients with lung cancer receiving cisplatin-based chemotherapy, the addition of aprepitant to a 5-HT3 antagonist, dexamethasone, and metoclopramide improves protection against CINV when the conventional anti-emetic regimen fails.

A Randomized Double-Blind, Double-Dummy, Multicenter Trial of Azasetron versus Ondansetron to Evaluate Efficacy and Safety in the Prevention of Delayed Nausea and Vomiting Induced by Chemotherapy

Purpose

This study was conducted to evaluate the efficacy and safety of azasetron compared to ondansetron in the prevention of delayed chemotherapy-induced nausea and vomiting.

Materials and Methods

This study was a multi-center, prospective, randomized, double-dummy, double-blind and parallel-group trial involving 12 institutions in Korea between May 2005 and December 2005. A total of 265 patients with moderately and highly emetogenic chemotherapy were included and randomly assigned to either the azasetron or ondansetron group. All patients received azasetron (10 mg intravenously) and dexamethasone (20 mg intravenously) on day 1 and dexamethasone (4 mg orally every 12 hours) on days 2-4. The azasetron group received azasetron (10 mg orally) with placebo of ondansetron (orally every 12 hours), and the ondansetron group received ondansetron (8 mg orally every 12 hours) with placebo of azasetron (orally) on days 2-6.

Results

Over days 2-6, the effective ratio of complete response in the azasetron and ondansetron groups was 45% and 54.5%, respectively (95% confidence interval, -21.4 to 2.5%). Thus, the non-inferiority of azasetron compared with ondansetron in delayed chemotherapy-induced nausea and vomiting was not proven in the present study. All treatments were well tolerated and no unexpected drug-related adverse events were reported. The most common adverse events related to the treatment were constipation and hiccups, and there were no differences in the overall incidence of adverse events.

Conclusion

In the present study, azasetron showed inferiority in the control of delayed chemotherapy-induced nausea and vomiting compared with ondansetron whereas safety profiles were similar between the two groups.

Aprepitant: a neurokinin-1 receptor antagonist for the treatment of chemotherapy-induced nausea and vomiting

Chemotherapy-induced nausea and vomiting (CINV) is associated with a significant deterioration in quality of life, and although the use of 5-hydroxytryptamine-3 (5-HT3) receptor antagonists plus dexamethasone has significantly improved the control of acute CINV, delayed nausea and vomiting remain a significant clinical problem. Aprepitant (Emend), Merck) is the first agent available in the new drug class of neurokinin-1 receptor antagonists. When added to a standard regimen of a 5-HT3 receptor antagonist and dexamethasone in patients receiving highly emetogenic chemotherapy, it improves the complete response rate of acute CINV. Aprepitant also improves the complete response of delayed CINV when used in combination with dexamethasone compared with dexamethasone alone. Based on these studies, new guidelines for the prevention of CINV have been developed for patients receiving highly emetogenic chemotherapy. The use of aprepitant in patients receiving moderately emetogenic chemotherapy will await the review and analysis of recently completed Phase III trials. Aprepitant is a substrate, a moderate inhibitor and an inducer of cytochrome P450 (CYP)3A4 and CYP2C9. Drug interactions should be monitored when aprepitant is coadministered with agents affected by CYP3A4 and CYP2C9 isoenzymes. The safety and efficacy of aprepitant has not been established in pediatric or adolescent patients, and aprepitant has not been evaluated in the treatment of patients with established nausea and vomiting. Future studies may consider the use of aprepitant with current and other new agents in moderately and highly emetogenic chemotherapy, as well in the clinical settings of multiple-day chemotherapy and bone marrow transplantation.

Clinical practice guidelines on antiemetics in oncology

The tolerability of chemotherapy has been significantly improved by the advent of effective drugs and protocols for the amelioration of chemotherapy-induced nausea and vomiting. Variables such as the timing of nausea and vomiting (acute, delayed or anticipatory) and the emetogenicity of the chemotherapy must be taken into account in developing guidelines for antiemetic prophylaxis and treatment. Although there are a number of 5-hydroxytryptamine antagonists available, the clinical differences between them are small. The use of drugs with a different mechanism of action, such as the recently introduced neurokinin-1 receptor antagonist aprepitant, may be a useful adjunct to 5-hydroxytryptamine-3 receptor antagonists or steroid prophylaxis. The addition of aprepitant to standard antiemetic regimens increases the proportion of complete responses to antiemetic therapy. For the use of highly emetogenic chemotherapy in oncology a combination of 5-hydroxytryptamine-3 receptor antagonist, dexamethasone and aprepitant is recommended in the acute phase, and dexamethasone plus aprepitant during the subsequent days (many patients do not have their symptoms controlled by 5-hydroxytryptamine-3 receptor antagonist and steroid alone). In either case, lorazepam can be added as required. For moderately emetogenic chemotherapy, a regimen of 5-hydroxytryptamine, dexamethasone and aprepitant is recommended in the acute phase, followed by aprepitant alone in the delayed phase. Alternatively, a 5-hydroxytryptamine-3 receptor antagonist and dexamethasone can be used in the acute phase, followed by dexamethasone for prophylaxis in the delayed phase. For chemotherapy with a low emetogenicity, either dexamethasone, metoclopramide, prochlorperazine or triethyperazine alone is recommended. No prophylaxis is generally required during the delayed phase and indeed may not be necessary during the acute phase either.

Maropitant prevented vomiting but not gastroesophageal reflux in anesthetized dogs premedicated with acepromazine-hydromorphone

OBJECTIVE

To evaluate the efficacy of maropitant for prevention of vomiting and gastroesophageal reflux (GER) in dogs following acepromazine-hydromorphone premedication and inhalation anesthesia.

STUDY DESIGN

Randomized, blinded, prospective clinical study.

ANIMALS

Twenty-six dogs admitted for elective soft tissue or orthopedic procedures that were 3.1 ±3.1 years of age and weighed 20.5 ± 11.4 kg.

METHODS

Dogs were randomly assigned to one of two groups: Group M received maropitant (1.0 mg kg(-1) ) and Group S received 0.9% saline (0.1 mL kg(-1) ) intravenously 45-60 minutes before premedication with hydromorphone (0.1 mg kg(-1) ) and acepromazine (0.03 mg kg(-1) ) intramuscularly. An observer blinded to treatment documented any retching or vomiting for 20 minutes before induction with propofol (2-6 mg kg(-1) ) and inhalation anesthesia. A pH probe inserted into the distal esophagus was used to detect GER.

RESULTS

None of the dogs in Group M retched or vomited (0/13), 6/13 (46%) in Group S were observed to retch or vomit, and the difference between groups was significant (p = 0.015). There were no differences between groups in the number of dogs with GER (Group M: 4/13, Group S: 6/13 dogs) or the number of reflux events. Esophageal pH at the end of anesthesia was significantly lower in both M and S groups in dogs with GER versus dogs without GER (p = 0.004 and 0.011, respectively). Only dogs with GER in Group S had significantly lower pH at the end compared to the beginning of anesthesia (p = 0.004).

CONCLUSIONS AND CLINICAL RELEVANCE

Intravenous maropitant prevented retching and vomiting associated with acepromazine-hydromorphone premedication. Maropitant did not prevent the occurrence of GER. Fewer dogs in Group M developed GER but further study with a larger number of dogs is necessary to determine if there is a significant difference.

Opioid induced nausea and vomiting

Opioids are broad spectrum analgesics that are an integral part of the therapeutic armamentarium to combat pain in the palliative care population. Unfortunately, among the adverse effects of opioids that may be experienced along with analgesia is nausea, vomiting, and/or retching. Although it is conceivable that in the future, using combination agents (opioids combined with agents which may nullify emetic effects), currently nausea/vomiting remains a significant issue for certain patients. However, there exists potential current strategies that may be useful in efforts to diminish the frequency and/or intensity of opioid-induced nausea/vomiting (OINV).

Current pharmacotherapy for chemotherapy-induced nausea and vomiting in cancer patients

INTRODUCTION

Nausea and vomiting are two of the most frequent and troubling side effects patients experience during chemotherapy, interfering with compliance with cancer therapies and quality of life. While newly available treatments have improved our ability to manage nausea and vomiting, anticipatory and delayed nausea and vomiting are still major problems for patients receiving chemotherapy. Many cancer patients consider delaying future chemotherapy cycles and some contemplate stopping chemotherapy altogether because of their fear of experiencing further nausea and vomiting.

AREAS COVERED

The purpose of this article is to provide an overview of the pathopsychophysiology of chemotherapy-induced nausea and vomiting (CINV), the recommended guidelines for treatment, and current agents in late-stage clinical trials, and future research needs to address the continued challenges of treatment-related nausea and vomiting.

EXPERT OPINION

Despite advances in pharmaceutical and behavioral therapies, and the provision of standard clinical guidelines for effectively managing CINV, patients continue to experience it. Moreover, control of nausea, acute and delayed, and anticipatory nausea and vomiting remains an important, unmet need among cancer patients. It is critical to focus attention on better understanding the mechanisms underlying nausea, anticipatory symptoms and delayed symptoms.

Management of chemotherapy-induced nausea and vomiting : focus on newer agents and new uses for older agents

Chemotherapy-induced nausea and vomiting (CINV) is associated with a significant deterioration in quality of life. The emetogenicity of the chemotherapeutic agents, repeated chemotherapy cycles, and patient risk factors significantly influence CINV. The use of a combination of a serotonin 5-HT3 receptor antagonist, dexamethasone and a neurokinin 1 (NK1) receptor antagonist has significantly improved the control of acute and delayed emesis in single-day chemotherapy. Palonosetron, a second-generation 5-HT3 receptor antagonist with a different half-life, a different binding capacity and a different mechanism of action than the first-generation 5-HT3 receptor antagonists appears to be the most effective agent in its class. Aprepitant, the first and only agent clinically available in the NK1 receptor antagonist drug class has been used effectively as an additive agent to the 5-HT3 receptor antagonists and dexamethasone to control CINV. Rolapitant and netupitant are other NK1 receptor antagonists that are currently in phase III clinical trials. Despite the control of emesis, nausea has not been well controlled by current agents. Olanzapine, a US-FDA approved antipsychotic, has emerged in recent trials as an effective preventative agent for CINV, as well as a very effective agent for the treatment of breakthrough emesis and nausea. Clinical trials using gabapentin, cannabinoids and ginger have not been definitive regarding their efficacy in the prevention of CINV. Additional studies are necessary for the control of nausea and for the control of CINV in the clinical settings of multiple-day chemotherapy and bone marrow transplantation.

Prevention of chemotherapy-induced nausea and vomiting and the role of neurokinin 1 inhibitors: from guidelines to clinical practice in solid tumors

A significant proportion of cancer patients experience nausea or vomiting during the course of their disease, either because of the cancer itself or because of the treatment received. Highly or moderately emetogenic drugs are part of the standard chemotherapy regimens frequently used in patients with lung cancer, breast cancer, ovarian cancer, and several other common solid tumors. In this review, we describe the impact of nausea and vomiting in patients receiving chemotherapy, and the main progress achieved in the prophylaxis of chemotherapy-induced nausea and vomiting with the introduction of neurokinin 1 inhibitors. The adherence to existing guidelines is particularly important to avoid suboptimal prophylaxis and maximize patients' outcome. This review is focused on lung, breast, ovarian, and colorectal cancer, which are among the solid tumors characterized by a numeric and clinical relevance of the chemotherapy-induced nausea and vomiting issue because of the wide use of highly and/or moderately emetogenic chemotherapy regimens.

An update on palonosetron hydrochloride for the treatment of radio/chemotherapy-induced nausea and vomiting

INTRODUCTION

Nausea and vomiting are well recognized in different clinical situations, suggesting that no single mechanism is likely to be responsible for their production. Chemotherapy-induced nausea and vomiting (CINV) can have a negative impact on quality of life and this may lead to a refusal of curative therapy or to a decline in palliative benefits offered by cytotoxic treatment. Palonosetron is a new agent in the class of 5-HT3 receptor antagonists (5-HT3RAs), and differs from the other agents by its higher receptor-binding affinity and longer half-life. These pharmacological properties have resulted in improved antiemetic activity in clinical trials, particularly in the treatment of delayed CINV following moderate emetogenic chemotherapy (MEC).

AREA COVERED

A systematic review of the medical literature was completed to inform this update. MEDLINE, the Cochrane Collaboration Library and meeting materials from ASCO and MASCC were all searched.

EXPERT OPINION

Palonosetron was the only serotonin receptor antagonist approved for prevention of delayed CINV caused by MEC and its use was incorporated in guideline recommendations. To date, several treatment settings such as multiple day chemotherapy require further studies to improve emesis related to therapy.

Aprepitant for prevention of nausea and vomiting secondary to high-dose cyclophosphamide administered to patients undergoing autologous peripheral blood stem cells mobilization: a phase II trial

This is a phase II trial evaluating efficacy and safety of aprepitant (AP) in combination with 5-HT3 antagonist and adjusted dose dexamethasone in patients receiving high-dose cyclophosphamide (CY) and filgrastim for stem cell mobilization. We used Simon's optimal two-stage design constrained to fewer than 40 patients with 10% type I error and 85% statistical power. The first stage of the study required accrual of 18 response-evaluable patients. The primary endpoint was the control of vomiting without the use of any rescue anti-emetics at 24 h after the administration of high dose CY (4 g/m(2)). If emesis was controlled in ≥9 patients, an additional cohort of 17 patients would be enrolled. The null hypothesis would be rejected if there were ≥20 responses among 35 patients. Forty patients were enrolled, five of whom were not evaluable for response. Eighteen evaluable patients were enrolled in the first stage. Acute emesis was controlled in 10 patients; therefore, enrollment proceeded to stage 2. An additional 17 patients were enrolled; 20/35 response-evaluable patients (57%) did not develop acute vomiting or require rescue anti-emetics, thus achieving the goal of the study. A total of 22/35 response-evaluable patients (63%) met the secondary endpoint of delayed emesis control (days 2-5). Thirty-three out of 35 patients underwent successful stem cell mobilization. No ≥ grade 3 AP-related adverse events were noted. The AP regimen can effectively control acute and delayed emesis in the majority patients receiving high-dose CY.

Evolving treatment paradigms for chemotherapy-induced nausea and vomiting

BACKGROUND

Chemotherapy-induced nausea and vomiting (CINV) is one of the most debilitating toxicities associated with cancer treatment. Although effective antiemetic agents are available, their use in practice often is suboptimal.

METHODS

The author reviews the pathophysiology of CINV as well as the drug classes and cost considerations that should be incorporated into treatment planning.

RESULTS

Several drug classes, including 5-hydroxytryptamine-3 receptor antagonists, neurokinin-1 receptor antagonists, and corticosteroids, are effective, especially when used in combination. Older antiemetic agents, such as prochlorperazine and metoclopramide, as well as olanzapine may provide reasonable alternatives in certain settings.

CONCLUSIONS

Interventions for CINV should include standard-of-care antiemetics combined with corticosteroids. The cost of using older, less expensive antiemetics may be outweighed by the expenditures to rescue patients after suboptimal prophylaxis, as well as the indirect costs of missed work and lost productivity.

NK-1 receptor antagonists as antitumor drugs: a survey of the literature from 2000 to 2011

INTRODUCTION

After binding to the neurokinin (NK-1) receptor, substance P (SP) induces tumor cell proliferation, the migration of tumor cells (invasion and metastasis) and angiogenesis. By contrast, NK-1 receptor antagonists inhibit tumor cell proliferation (tumor cells die by apoptosis), block the migratory activity of tumor cells and exert antiangiogenic properties.

AREAS COVERED

This review offers a 12-year overview of the underlying mechanism of the action of the SP/NK-1 receptor system and NK-1 receptor antagonists in cancer, providing a new approach to the treatment of tumors.

EXPERT OPINION

Chemically diverse NK-1 receptor antagonists have been identified. The antitumor action of these compounds is independent of their chemical structures and such action is associated with their affinity for the NK-1 receptor and with the dose of the antagonist administered. The NK-1 receptor can be considered as a target in cancer treatment and NK-1 receptor antagonists could be considered as new antitumor drugs. The NK-1 receptor antagonist aprepitant is used in clinical practice and exerts an antitumor action against tumor cells in vitro. In the future, such antitumor action should be tested in human clinical trials.

The role of neurokinin-1 receptor in the microenvironment of inflammation and cancer

The recent years have witnessed an exponential increase in cancer research, leading to a considerable investment in the field. However, with few exceptions, this effort has not yet translated into a better overall prognosis for patients with cancer, and the search for new drug targets continues. After binding to the specific neurokinin-1 (NK-1) receptor, the peptide substance P (SP), which is widely distributed in both the central and peripheral nervous systems, triggers a wide variety of functions. Antagonists against the NK-1 receptor are safe clinical drugs that are known to have anti-inflammatory, analgesic, anxiolytic, antidepressant, and antiemetic effects. Recently, it has become apparent that SP can induce tumor cell proliferation, angiogenesis, and migration via the NK-1 receptor, and that the SP/NK-1 receptor complex is an integral part of the microenvironment of inflammation and cancer. Therefore, the use of NK-1 receptor antagonists as a novel and promising approach for treating patients with cancer is currently under intense investigation. In this paper, we evaluate the recent scientific developments regarding this receptor system, its role in the microenvironment of inflammation and cancer, and its potentials and pitfalls for the usage as part of modern anticancer strategies.

Supportive care in hemato-oncology: a review in light of the latest guidelines

Recent developments in cancer therapy have resulted in increases in treatment success rates and survival. One of thebasic goals of such therapy is improving patient quality of life. Chemotherapy protocols for solid or hematologicalmalignancies-most of which include multiple agents-negatively impact patient quality of life. Additionally, there havebeen developments in supportive care, which seeks to ameliorate or minimize the negative effects of chemotherapy.Herein we present a review and brief summarization of some of the agents used for supportive care in cancer patientsin light of the latest guidelines.