Reduction of cisplatin-induced emesis by a selective neurokinin-1-receptor antagonist. L-754,030 Antiemetic Trials Group

An assessment of the effects of neurokinin1 receptor antagonism against nausea and vomiting: Relative efficacy, sites of action and lessons for future drug development

A broad-spectrum anti-vomiting effect of neurokinin1 receptor antagonists (NK1 RA), shown in pre-clinical animal studies, has been supported by a more limited range of clinical studies in different indications. However, this review suggests that compared with vomiting, the self-reported sensation of nausea is less affected or possibly unaffected (depending on the stimulus) by NK1 receptor antagonism, a common finding for anti-emetics. The stimulus-independent effects of NK1 RAs against vomiting are explicable by actions within the central pattern generator (ventral brainstem) and the nucleus tractus solitarius (NTS; dorsal brainstem), with additional effects on vagal afferent activity for certain stimuli (e.g., highly emetogenic chemotherapy). The central pattern generator and NTS neurones are multifunctional so the notable lack of obvious effects of NK1 RAs on other reflexes mediated by the same neurones suggests that their anti-vomiting action is dependent on the activation state of the pathway leading to vomiting. Nausea requires activation of cerebral pathways by projection of information from the NTS. Although NK1 receptors are present in cerebral nuclei implicated in nausea, and imaging studies show very high receptor occupancy at clinically used doses, the variable or limited ability of NK1 RAs to inhibit nausea emphasizes: (i) our inadequate understanding of the mechanisms of nausea; and (ii) that classification of a drug as an anti-emetic may give a false impression of efficacy against nausea vs. vomiting. We discuss the potential mechanisms for the differential efficacy of NK1 RA and the implications for future development of drugs that can effectively treat nausea, an area of unmet clinical need.

Exploring the potential hypothalamic role in mediating cisplatin-induced negative energy balance

Cisplatin is a chemotherapeutic drug commonly used for treating different types of cancer. However, long-term use can lead to side effects, including anorexia, nausea, vomiting, and weight loss, which negatively affect the patient's quality of life and ability to undergo chemotherapy. This study aimed to investigate the mechanisms underlying the development of a negative energy balance during cisplatin treatment. Mice treated with cisplatin exhibit reduced food intake, body weight, and energy expenditure. We observed altered neuronal activity in the hypothalamic nuclei involved in the regulation of energy metabolism in cisplatin-treated mice. In addition, we observed activation of microglia and inflammation in the hypothalamus following treatment with cisplatin. Consistent with this finding, inhibition of microglial activation effectively rescued cisplatin-induced anorexia and body weight loss. The present study identified the role of hypothalamic neurons and inflammation linked to microglial activation in the anorexia and body weight loss observed during cisplatin treatment. These findings provide insight into the mechanisms underlying the development of metabolic abnormalities during cisplatin treatment and suggest new strategies for managing these side effects.

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.

The Role of Substance P Within Traumatic Brain Injury and Implications for Therapy

This review examines the role of the neuropeptide substance P within the neuroinflammation that follows traumatic brain injury. It examines it in reference to its preferential receptor, the neurokinin-1 receptor, and explores the evidence for antagonism of this receptor in traumatic brain injury with therapeutic intent. Expression of substance P increases following traumatic brain injury. Subsequent binding to the neurokinin-1 receptor results in neurogenic inflammation, a cause of deleterious secondary effects that include an increased intracranial pressure and poor clinical outcome. In several animal models of TBI, neurokinin-1 receptor antagonism has been shown to reduce brain edema and the resultant rise in intracranial pressure. A brief overview of the history of substance P is presented, alongside an exploration into the chemistry of the neuropeptide with a relevance to its functions within the central nervous system. This review summarizes the scientific and clinical rationale for substance P antagonism as a promising therapy for human TBI.

Modulatory effects of phytol on the antiemetic property of domperidone, possibly through the D2 receptor interaction pathway: in vivo and in silico studies

The current study is designed to evaluate the antiemetic effect of the diterpenoid phytol (PHY) using in vivo and in silico studies. For this, emesis was induced in 4-day-old chicks by the oral administration of copper sulfate (CuSO4.5H2O) at 50 mg/kg. To see the possible antiemetic mechanism of PHY, we used a number of reference drugs such as domperidone (80 mg/kg), ondansetron (24 mg/kg) and hyoscine (100 mg/kg) as positive controls, while the vehicle served as a negative control group. PHY was administered orally at the doses of 50 and 75 mg/kg. Both PHY and reference drugs were given alone or in combined groups to evaluate their synergistic or antagonistic effects on the chicks. Molecular docking of PHY and reference drugs was carried out against 5HT3, D2, D3, H1, NK1, and mAChRs (M1-M5) receptors for estimating binding affinity to the receptors. Drug-receptor interactions and active sites of the receptors were observed with the aid of different computational tools. The drug-likeness and pharmacokinetics of all the drugs were predicted through the SwissADME online database. The results suggest that PHY reduces the mean number of retches and increases latency dose-dependently in the birds. In the combination groups, PHY75 showed better antiemetic effects with domperidone and ondansetron. In addition, PHY exhibited the highest binding affinity with the D2 receptor (6CM4) (- 7.3 kcal/mol). In conclusion, PHY showed an antiemetic activity in chicks, possibly through the D2 receptor interaction pathway.

Anti-emetic effects of thalidomide: Evidence, mechanism of action, and future directions

The rationale for using thalidomide (THD) as a treatment for nausea and vomiting during pregnancy in the late 1950s appears to have been based on its sedative or hypnotic properties. In contrast to contemporaneous studies on the anti-emetic activity of phenothiazines, we were unable to identify publications reporting preclinical or clinical evaluation of THD as an anti-emetic. Our survey of the literature revealed a clinical study in 1965 showing THD reduced vomiting in cancer chemotherapy which was substantiated by similar studies from 2000, particularly showing efficacy in the delayed phase of chemotherapy-induced nausea and vomiting. To identify the mechanism(s) potentially involved in thalidomide's anti-emetic activity we reviewed its pharmacology in the light of nausea and vomiting mechanisms and their pharmacology with a particular emphasis on chemotherapy and pregnancy. The process identified the following potential mechanisms: reduced secretion of Growth Differentiation Factor 15, suppression of inflammation/prostaglandin production, downregulation of cytotoxic drug induced upregulation of iNOS, and modulation of BK (KCa1.1) channels and GABAA/glutamate transmission at critical points in the emetic pathways (nucleus tractus solitarius, area postrema). We propose ways to investigate these hypothesized mechanisms and discuss the associated challenges (e.g., objective quantification of nausea) in addition to some of the more general aspects of developing novel drugs to treat nausea and vomiting.

Use of long term aprepitant as a treatment for refractory nausea following oesophageal stent insertion - a case report

BACKGROUND

Aprepitant, a substance P neurokinin-1 receptor antagonist, is licenced for the prevention of acute and delayed nausea and vomiting associated with highly and moderately emetogenic cancer chemotherapy.

CASE

A 33 year-old male with metastatic gastro-oesophageal cancer had multiple admissions for refractory nausea and vomiting following insertion of an oesophageal stent.

ACTION

Mechanical issues with the stent, stent removal and central causes were excluded. Multiple anti-emetic agents were trialled in combination and with varying routes of administration without significant symptomatic improvement.

FORMULATION

A trial of aprepitant was proposed as an off-licence therapy.

OUTCOME

One hundred sixty-five milligrammes of aprepitant was given orally every 3 days and then up titrated to once daily with significant symptomatic improvement enabling the patient to tolerate an oral diet. The patient remained stable at 12 weeks and has been accepted into two clinical trials for potential further cancer treatment.

LESSONS

Aprepitant can be effective in refractory nausea and vomiting outside of emetogenic chemotherapy and safely used as a chronic treatment. The prevalence of refractory nausea and vomiting as a rare adverse outcome post-oesophageal stent insertion should be studied.

WHAT NOW?

Further research of neurokinin-1 inhibitors for indications other than chemotherapy-induced nausea and vomiting is indicated.

Prevention of Chemotherapy-Induced Nausea and Vomiting in the Older Patient: Optimizing Outcomes

Chemotherapy-induced nausea and vomiting (CINV) are still two of the most feared side effects of cancer therapy. Although major progress in the prophylaxis of CINV has been made during the past 40 years, nausea in particular remains a significant problem. Older patients have a lower risk of CINV than younger patients, but are at a higher risk of severe consequences of dehydration and electrolyte disturbances following emesis. Age-related organ deficiencies, comorbidities, polypharmacy, risk of drug–drug interactions, and lack of compliance all need to be addressed in the older patient with cancer at risk of CINV. Guidelines provide evidence-based recommendations for the prophylaxis of CINV, but none of these guidelines offer specific recommendations for older patients with cancer. This means that the recommendations may lead to overtreatment in some older patients. This review describes the development of antiemetic prophylaxis of CINV focusing on older patients, summarizes recommendations from antiemetic guidelines, describes deficiencies in our knowledge of older patients, summarizes necessary precautions, and suggests some future perspectives for antiemetic research in older patients.

Single-dose netupitant/palonosetron versus 3-day aprepitant for preventing chemotherapy-induced nausea and vomiting: a pooled analysis

Aim: In the absence of comparative studies, guidelines consider neurokinin 1 receptor antagonists (RAs) as interchangeable. We evaluated the pooled efficacy from three cisplatin registration trials, each with arms containing netupitant/palonosetron (NEPA), a fixed neurokinin 1 RA (netupitant)/serotonin Type 3 (5-HT3) RA (palonosetron) combination, and an aprepitant (APR) regimen. Materials & methods: Efficacy data were pooled for rates of complete response (CR: no emesis/no rescue medication), complete protection (CR + no significant nausea), total control (CR + no nausea) and no significant nausea during acute (0-24 h), delayed (>24-120 h) and overall (0-120 h) phases post chemotherapy. Results: Among 621 NEPA and 576 APR patients, response rates were similar for the acute phase, and generally favored NEPA during delayed and overall phases. CR rates for NEPA versus APR were 88.4 versus 89.2%, 81.8 versus 76.9% (p < 0.05) and 78.4 versus 75.0% during the acute, delayed and overall phases, respectively. Conclusion: Oral NEPA administered on day 1 was more effective than a 3-day APR regimen in preventing delayed nausea and vomiting associated with cisplatin.

Antiemetic regimen with aprepitant in the prevention of chemotherapy-induced nausea and vomiting: An updated systematic review and meta-analysis

OBJECTIVE

To systematically evaluate the efficacy and safety of antiemetic regimen with aprepitant in the prevention of chemotherapy-induced nausea and vomiting (CINV) and provide updated information for clinical practice.

METHODS

Pubmed, Embase, the Cochrane Library, and 3 Chinese literature databases were systematically searched. Randomized controlled trials comparing standard regimen (5-hydroxytryptamine-3 receptor antagonist and glucocorticoid) with aprepitant triple regimen (aprepitant plus the standard regimen) for preventing CINV were screened. Literature selection, data extraction, and quality evaluation were performed by 2 reviewers independently. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated in the meta-analysis using RevMan 5.3 software.

RESULTS

A total of 51 randomized controlled trials were finally included in the systematic review. Compared with the standard regimen, the aprepitant triple regimen significantly improved the complete response in the overall (OR 1.88, 95% CI 1.71-2.07), acute (OR 1.96, 95% CI 1.65-2.32) and delayed (OR 1.96, 95% CI 1.70-2.27) phases, regardless of emetogenic risk of chemotherapy. Aprepitant could also significantly enhance the proportions of patients who have no emesis, nausea, or use of rescue medication respectively in the overall, acute and/or delayed phases. Aprepitant was found to be associated with decreased risk of constipation (OR 0.85, 95% CI 0.74-0.97), but increased the incidence of hiccup (OR 1.26, 95% CI 1.05, 1.51). There were no statistically significant differences between the 2 groups on other safety outcomes.

CONCLUSION

The aprepitant triple regimen is effective for the prevention of CINV in patients being treated with moderately or highly emetogenic chemotherapy, and has a significant tendency to reduce the risk of constipation and increase the incidence of hiccup.

[18F]SPA-RQ/PET Study of NK1 receptors in the Whole Body of Guinea Pig and Rat

There is a substantial interest in the development of NK1 substance P antagonists as potential treatments for various neuropsychiatric and somatic disorders. The aim of this study was to determine whether [¹⁸F]SPA-RQ can be utilized as a tool for studying the whole body distribution and function of NK1 receptors in preclinical settings. The compound was injected into guinea pigs with or without premedication with a NK1 receptor antagonist (NK1A-2). For comparison, we included two rats in the study, as the affinity of antagonists for NK1 receptors is known to vary between species. The whole body biodistribution of the tracer was determined at several time points. The tracer showed specific binding in organs compatible with the known location of NK1-receptors. Premedication with a NK1 antagonist led to an inhibited uptake of [¹⁸F]SPA-RQ in several organs of guinea pigs, notably intestine, pancreas, urinary bladder, uterus, skin and lung. Specific binding was also seen in both cortex and striatum. In contrast, negligible specific binding was observed in the rat brain with [¹⁸F]SPA-RQ, whereas the tracer uptake in peripheral tissues was similar to that seen in guinea pigs. We conclude that [¹⁸F]SPA-RQ/PET is a useful tool to study the distribution and function of peripherally located NK1 receptors e.g. in different disease models.

Guidelines on management of cyclic vomiting syndrome in adults by the American Neurogastroenterology and Motility Society and the Cyclic Vomiting Syndrome Association

The increasing recognition of cyclic vomiting syndrome (CVS) in adults prompted the development of these evidence-based guidelines on the management of CVS in adults, which was sponsored by the American Neurogastroenterology and Motility Society (ANMS) and the Cyclic Vomiting Syndrome Association (CVSA). GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) framework was used and a professional librarian performed the literature search. The expert committee included the President of the CVSA who brought a patient perspective into the deliberations. The committee makes recommendations for the prophylaxis of CVS, treatment of acute attacks, diagnosis, and overall management of CVS. The committee strongly  recommends that adults with moderate-to-severe CVS receive a tricyclic antidepressant (TCA), such as amitriptyline, as a first-line prophylactic medication and receive topiramate or aprepitant as alternate prophylactic medications. Zonisamide or levetiracetam and mitochondrial supplements (Coenzyme Q10, L-carnitine, and riboflavin) are conditionally recommended as alternate prophylactic medications, either alone or concurrently with other prophylactic medications. For acute attacks, the committee conditionally recommends using serotonin antagonists, such as ondansetron, and/or triptans, such as sumatriptan or aprepitant to abort symptoms. Emergency department treatment is best achieved with the use of an individualized treatment protocol and shared with the care team (example provided). The committee recommended screening and treatment for comorbid conditions such as anxiety, depression, migraine headache, autonomic dysfunction, sleep disorders, and substance use with referral to appropriate allied health services as indicated. Techniques like meditation, relaxation, and biofeedback may be offered as complementary therapy to improve overall well-being and patient care outcomes.

Evaluation of aprepitant and fosaprepitant in pediatric patients

BACKGROUND

Single-dose i.v. fosaprepitant has been approved as an alternative to 3 day oral aprepitant, a neurokinin-1 receptor antagonist, and improves prevention of chemotherapy-induced nausea and vomiting (CINV). Because fosaprepitant has shown similar efficacy to aprepitant in adult patients only, this study compared the efficacy and safety of aprepitant and fosaprepitant in pediatric patients.

METHODS

Children younger than 18 years who received aprepitant or fosaprepitant to manage CINV between January 2015 and March 2018 at the National Cancer Center Hospital (Tokyo) were recruited to this study. The primary endpoint was complete response (CR; no vomiting/rescue medication) between 0 and 120 h after the start of chemotherapy. Secondary endpoints were safety based on the frequency of severe adverse events, and evaluation of patient characteristics as risk factors (effect of age and sex).

RESULTS

A total of 125 chemotherapy cycles were evaluated. In the aprepitant group, CR was observed in 36 of 80 treatment cycles (45.0%), whereas in the fosaprepitant group, it was observed in 19 of 45 cycles (42.2%; P = 0.852). No treatment-related severe adverse events were observed in either group. The number of non-CR was greater than that of CR in patients aged 6-14 years. The difference in CR rate between male and female patients was not statistically significant (47.1% vs 40.0%, respectively; P = 0.471).

CONCLUSIONS

Aprepitant and fosaprepitant were safely used and may be equally useful for pediatric patients receiving highly emetogenic chemotherapy. CR rate may be associated with patient age.

Efficacy, Tolerability and Pharmacokinetic Impact of Aprepitant in Sarcoma Patients Receiving Ifosfamide and Doxorubicin Chemotherapy: A Randomized Controlled Trial

INTRODUCTION

Aprepitant, a selective neurokinin-1 receptor antagonist approved for prevention of chemotherapy-induced nausea and vomiting (CINV), is an inhibitor of the cytochrome P450 3A4 (CYP3A4) enzyme, which is involved in the clearance of several chemotherapeutic agents. Here we evaluated the efficacy and toxicity of a combination of aprepitant, palonosetron, and dexamethasone as antiemetic prophylaxis in sarcoma patients receiving ifosfamide and doxorubicin chemotherapy, and examined the potential of aprepitant to affect the pharmacokinetics of ifosfamide, which is primarily metabolized by CYP3A4.

METHODS

A total of 108 sarcoma patients were randomly assigned to either the aprepitant group (antiemetic regimen: aprepitant, palonosetron, and dexamethasone) or the control group (antiemetic regimen: palonosetron and dexamethasone). Data on nausea, vomiting, and use of rescue medication were collected, and the primary efficacy end point was the proportion of patients with complete response (CR), defined as no vomiting and no use of rescue therapy during 120 h after initiation of chemotherapy. Tolerability was evaluated on the basis of reported adverse events and laboratory assessments. Blood samples for ifosfamide pharmacokinetic analysis were collected in ten patients.

RESULTS

The percentage of patients achieving CR was significantly higher in the aprepitant group compared with that in the control group in the acute, delay, and overall phase (78.4% vs. 59.3%, 74.5% vs. 48.1%, and 68.6% vs. 37.0%, p < 0.05, respectively). No significant differences of adverse events or hematological toxicity were detected between the two groups. Concomitant administration of aprepitant did not cause any statistically significant changes in ifosfamide pharmacokinetics. Values for aprepitant group vs. control group were as follows: geometric mean of C_max was 119 vs. 120 ng/mL, AUC_0-last was 648 vs. 635 ng h/mL, AUC_0-inf was 681 vs. 668 ng h/mL, plasma clearance was 4.40 vs. 4.49 (L/h/m²), respectively; harmonic means of t_1/2 was 2.11 vs. 2.25 h.

CONCLUSIONS

This study showed that aprepitant in combination with palonosetron and dexamethasone was safe and effectively controlled CINV in sarcoma patients receiving ifosfamide and doxorubicin chemotherapy. Aprepitant may have a low potential to affect the pharmacokinetics of chemotherapeutic agents metabolized by CYP3A4.

A History of Drug Discovery for Treatment of Nausea and Vomiting and the Implications for Future Research

The origins of the major classes of current anti-emetics are examined. Serendipity is a recurrent theme in discovery of their anti-emetic properties and repurposing from one indication to another is a continuing trend. Notably, the discoveries have occurred against a background of company mergers and changing anti-emetic requirements. Major drug classes include: (i) Muscarinic receptor antagonists-originated from historical accounts of plant extracts containing atropine and hyoscine with development stimulated by the need to prevent sea-sickness among soldiers during beach landings; (ii) Histamine receptor antagonists-searching for replacements for the anti-malaria drug quinine, in short supply because of wartime shipping blockade, facilitated the discovery of histamine (H1) antagonists (e.g., dimenhydrinate), followed by serendipitous discovery of anti-emetic activity against motion sickness in a patient undergoing treatment for urticaria; (iii) Phenothiazines and dopamine receptor antagonists-investigations of their pharmacology as "sedatives" (e.g., chlorpromazine) implicated dopamine receptors in emesis, leading to development of selective dopamine (D2) receptor antagonists (e.g., domperidone with poor ability to penetrate the blood-brain barrier) as anti-emetics in chemotherapy and surgery; (iv) Metoclopramide and selective 5-hydroxytryptamine3(5-HT3) receptor antagonists-metoclopramide was initially assumed to act only via D2 receptor antagonism but subsequently its gastric motility stimulant effect (proposed to contribute to the anti-emetic action) was shown to be due to 5-hydroxytryptamine4 receptor agonism. Pre-clinical studies showed that anti-emetic efficacy against the newly-introduced, highly emetic, chemotherapeutic agent cisplatin was due to antagonism at 5-HT3 receptors. The latter led to identification of selective 5-HT3 receptor antagonists (e.g., granisetron), a major breakthrough in treatment of chemotherapy-induced emesis; (v) Neurokinin1receptor antagonists-antagonists of the actions of substance P were developed as analgesics but pre-clinical studies identified broad-spectrum anti-emetic effects; clinical studies showed particular efficacy in the delayed phase of chemotherapy-induced emesis. Finally, the repurposing of different drugs for treatment of nausea and vomiting is examined, particularly during palliative care, and also the challenges in identifying novel anti-emetic drugs, particularly for treatment of nausea as compared to vomiting. We consider the lessons from the past for the future and ask why there has not been a major breakthrough in the last 20 years.

A phase 2 study of fosaprepitant combined with high-dose dexamethasone for Japanese cancer patients receiving highly emetogenic chemotherapy

PURPOSE

Combination therapy of fosaprepitant, dexamethasone (DEX) and a serotonin (5-HT3) receptor antagonist is a standard antiemetic prophylaxis for patients receiving highly emetogenic chemotherapy (HEC). However, the appropriate dose of DEX has not been established in Japan. This study determined the efficacy and safety of triplet antiemetic prophylaxis in Japanese patients receiving HEC when administered the same doses of DEX as those given in a previous international phase 3 study on this drug.

METHODS

To assess the efficacy and safety of a sufficient dose of DEX (12 mg on day 1, 8 mg on day 2, 16 mg on days 3 and 4) in combination with intravenous fosaprepitant and granisetron, we prospectively examined patients receiving HEC including cisplatin (≥50 mg/m). The primary endpoint was to determine the percentage of patients who had achieved a complete response (CR), which was defined as no vomiting and no rescue therapy during the entire treatment course.

RESULTS

Between February 2013 and January 2015, 44 patients were enrolled with a median age of 65 years (range, 30-75). There were 34 males (77.3%) in the study. Most of the patients had upper gastrointestinal cancers. The CR rate during the treatment course was 70% (95% confidence interval [CI]: 55%-83%) in the overall phase and 91% (95% CI: 78%-97%) in the acute phase and 70% (95% CI: 55%-83%) in the delayed phase. Appreciable severe toxicities related to the antiemetic therapy were not observed.

CONCLUSIONS

These results suggest that a sufficient dose of DEX in combination with fosaprepitant and granisetron is optimal as an antiemetic prophylaxis for Japanese patients receiving HEC.

A phase II randomised study to evaluate the efficacy of aprepitant plus palonosetron for preventing delayed-phase CINV associated with TC therapy in gynaecological cancer

AIM

Chemotherapy-induced nausea and vomiting (CINV) is one of the most frequently encountered side effects of cancer treatment. Severe CINV can lead patients to refuse chemotherapy, which ultimately affects cancer outcomes. The development of fairly new antiemetic agents, 5-hydroxytryptamine-3 receptor antagonists, palonosetron and neurokinin-1 receptor antagonists and aprepitant has reduced the risk and incidence of CINV. In this study, we assessed the efficacy of aprepitant plus palonosetron against palonosetron for CINV in patients receiving moderately emetic cancer chemotherapy (paclitaxel and carboplatin combination [TC] therapy).

METHODS

Between November 2010 and March 2014, 78 patients with gynecological cancer treated with TC therapy were randomized into two groups: an aprepitant group (administered aprepitant, dexamethasone and palonosetron) and a control group (administered dexamethasone and palonosetron). The primary study endpoint was complete response, defined as the complete absence of emetic events in the delayed phase.

RESULTS

The complete response rate in the delayed phase differed significantly between the two groups, with 82% in the aprepitant group and 97% in the control group (P = 0.025).

CONCLUSION

The combination of aprepitant and palonosetron appears to be of greater efficacy than palonosetron alone for the prevention of delayed-phase CINV induced by TC therapy.

Targeting tachykinin receptors in neuroblastoma

Neuroblastoma is the most common extracranial tumor in children. Despite aggressive multimodal treatment, high-risk neuroblastoma remains a clinical challenge with survival rates below 50%. Adding targeted drugs to first-line therapy regimens is a promising approach to improve survival in these patients. TACR1 activation by substance P has been reported to be mitogenic in cancer cell lines. Tachykinin receptor (TACR1) antagonists are approved for clinical use as an antiemetic remedy since 2003. Tachykinin receptor inhibition has recently been shown to effectively reduce growth of several tumor types. Here, we report that neuroblastoma cell lines express TACR1, and that targeting TACR1 activity significantly reduced cell viability and induced apoptosis in neuroblastoma cell lines. Gene expression profiling revealed that TACR1 inhibition repressed E2F2 and induced TP53 signaling. Treating mice harboring established neuroblastoma xenograft tumors with Aprepitant also significantly reduced tumor burden. Thus, we provide evidence that the targeted inhibition of tachykinin receptor signaling shows therapeutic efficacy in preclinical models for high-risk neuroblastoma.

Chemotherapy-Induced Pica in Rats Reduced by Electroacupuncture

OBJECTIVES

Acupuncture or electroacupuncture (EA) has been applied for treating chemotherapy-induced emesis with limited success. The aims of this study were to investigate the anti-emetic effect of EA and to explore underlying anti-emetic mechanisms.

MATERIALS AND METHODS

Rats were chronically implanted with a pair of stainless steel leads at acupoint pericardium 6 (PC6). Effects of EA with different parameters on cisplatin-induced nausea were assessed by pica (intake of kaolin, a surrogate of nausea in species without vomiting reflex). C-fos expressions in the area postrema (AP) and nucleus tractus solitarii (NTS) were analyzed. Subdiaphragmatic vagotomy was used to study involvement of the vagal pathway.

RESULTS

1) EA at 20 Hz/0.6 msec reduced kaolin intake in the first and second days after cisplatin injection compared with the sham-EA group (first day: 1.0 ± 0.2 vs. 1.9 ± 0.3 g, p = 0.017; second day: 0.4 ± 0.2 vs.1.1 ± 0.3 g, p = 0.010). However, EA at 10 Hz/1.2 msec was ineffective on both days. 2) Subdiaphragmatic vagotomy significantly reduced cisplatin-induced kaolin intake (1.1 ± 0.3 vs. 2.2 ± 0.3 g, p = 0.014) and also blocked the inhibitory effect of EA on kaolin intake in the first day. 3) Cisplatin significantly increased the expression of c-fos in the NTS and AP. Vagotomy greatly reduced c-fos expression in both NTS and AP. EA reduced the cisplatin-induced c-fos expression in the AP but not the NTS.

CONCLUSIONS

EA at PC6 with appropriate parameters has an inhibitory effect on cisplatin-induced nausea. The anti-emetic effect of the EA is centrally medicated involving the AP via the vagal pathway as well as the potential effect on AP by reducing the release of hormones.

New options and controversies in the management of chemotherapy-induced nausea and vomiting

PURPOSE

An expanding array of options for prevention and treatment of chemotherapy-induced nausea and vomiting (CINV), including regimens containing olanzapine or recently approved neurokinin 1 (NK₁) receptor antagonists, are reviewed.

SUMMARY

Up to 80% of patients receiving chemotherapy have CINV. Current practice guidelines recommend that patients treated with highly emetogenic chemotherapy also receive a 3-drug antiemetic regimen initiated on the day of and continued for 3 days after chemotherapy administration, with the most commonly used 3-drug regimen consisting of an NK₁ receptor antagonist, a 5-hydroxytryptamine type 3 (5-HT₃) receptor antagonist, and dexamethasone. Developments in the area of CINV management in recent years include the use of olanzapine in combination with a 5-HT₃ antagonist and dexamethasone; Food and Drug Administration (FDA) approval of the NK₁ receptor antagonist rolapitant, which provides a longer duration of effect than aprepitant; FDA approval of a combination product containing palonosetron and the NK₁ receptor antagonist netupitant; and revisions of U.S. practice guidelines ending palonosetron's status as the preferred 5-HT₃ antagonist for prevention of CINV associated with moderately or highly emetogenic chemotherapy.

CONCLUSION

Newer therapeutic options for the management of CINV are equivalent to standard-of-care regimens in terms of efficacy and toxicity. While the NK₁ receptor antagonist rolapitant and a product combining palonosetron and netupitant have potential advantages over standard therapy in terms of convenience or pharmacologic properties, their relatively high costs must be considered.

Efficacy and Safety of Neurokinin-1 Receptor Antagonists for Prevention of Chemotherapy-Induced Nausea and Vomiting: Systematic Review and Meta-analysis of Randomized Controlled Trials

OBJECTIVES

Can addition of neurokinin-1 receptor antagonists (NK1-RAs) be considered as an ideal strategy for the prevention of chemotherapy-induced nausea and vomiting (CINV)? Researchers differ on this question.

MATERIALS AND METHODS

Electronic databases were searched for randomized control trials (RCTs) that evaluated the effectiveness and safety of NK1-RAs in preventing CINV. The primary end point was complete response (CR) in the acute, delayed, and overall phases after chemotherapy. Subgroup analyses evaluated the types of NK1-RAs, routines of administration, types of malignancies, regimens used in combination with NK1-RAs, and age of patients included in the studies. The incidences of different types of adverse events were also extracted to estimate the safety of NK1-RAs.

RESULTS

A total of 38 RCTs involving 13,923 patients were identified. The CR rate of patients receiving NK-RAs was significantly higher than patients in the control groups during overall phase (70.8% vs 56.0%, <0.001), acute phase (85.1% vs 79.6%, <0.001), and delayed phase (71.4% vs 58.2%, <0.001). There were three studies including patients of children or adolescents, the CR rate was also significantly higher in the treatment group (overall phase: OR=2.807, <0.001; acute phase: OR=2.863, P =0.012; delayed phase: OR=2.417, <0.001). For all the other outcomes, patients in the NK1-RAs groups showed improvements compared to the control groups (incidence of nausea: 45.2% vs 45.9%, <0.001; occurrence of vomiting: 22.6% vs 38.9%, <0.001; usage of rescue drugs: 23.5% vs 34.1%, <0.001). The pooled side effects from NK1-RAs did not significantly differ from previous reports and the toxicity rates in patients less than eighteen years old also did not diff between the two groups (P=0.497). However, we found that constipation and insomnia were more common in the patients of control groups, whereas diarrhea and hiccups were more frequently detected in patients receiving NK1-RAs.

CONCLUSIONS

NK1-RAs improved the CR rate of CINV. They are effective for both adults and children. The use of NK1-RAs might be associated with the appearance of diarrhea and hiccups, while decreasing the possibility of constipation and insomnia.

Loss of Neurokinin-1 Receptor Alters Ocular Surface Homeostasis and Promotes an Early Development of Herpes Stromal Keratitis

Substance P neuropeptide and its receptor, neurokinin-1 receptor (NK1R), are reported to present on the ocular surface. In this study, mice lacking functional NK1R exhibited an excessive desquamation of apical corneal epithelial cells in association with an increased epithelial cell proliferation and increased epithelial cell density, but decreased epithelial cell size. The lack of NK1R also resulted in decreased density of corneal nerves, corneal epithelial dendritic cells (DCs), and a reduced volume of basal tears. Interestingly, massive accumulation of CD11c+CD11b+ conventional DCs was noted in the bulbar conjunctiva and near the limbal area of corneas from NK1R-/- mice. After ocular HSV-1 infection, the number of conventional DCs and neutrophils infiltrating the infected corneas was significantly higher in NK1R-/- than C57BL/6J mice. This was associated with an increased viral load in infected corneas of NK1R-/- mice. As a result, the number of IFN-γ-secreting virus-specific CD4 T cells in the draining lymph nodes of NK1R-/- mice was much higher than in infected C57BL/6J mice. An increased number of CD4 T cells and mature neutrophils (CD11b+Ly6ghigh) in the inflamed corneas of NK1R-/- mice was associated with an early development of severe herpes stromal keratitis. Collectively, our results show that the altered corneal biology of uninfected NK1R-/- mice along with an enhanced immunological response after ocular HSV-1 infection causes an early development of herpes stromal keratitis in NK1R-/- mice.

Aprepitant for antiemesis after laparoscopic gynaecological surgery: A randomised controlled trial

BACKGROUND

Ondansetron, a 5-HT3 receptor antagonist, and aprepitant, a neurokinin-1 receptor antagonist, block the emetic effect of serotonin and neurokinin, respectively. Aprepitant combined with ondansetron can be more effective for preventing emesis in patients at high risk of postoperative nausea and vomiting (PONV).

OBJECTIVE

To investigate the prophylactic effect of combining aprepitant with ondansetron compared with ondansetron alone on PONV in patients with fentanyl-based patient-controlled analgesia (PCA) after laparoscopic gynaecological surgery.

DESIGN

Single-centre, double-blinded randomised controlled trial.

SETTING

A major university hospital in Seoul, Korea, between July 2012 and April 2013.

PATIENTS

One hundred and twenty-five female patients (American Society of Anesthesiologists' physical status 1 or 2) with fentanyl-based intravenous PCA after gynaecological laparoscopy were recruited to the study, and 110 completed the protocol.

INTERVENTIONS

Oral aprepitant 80 mg or placebo was given 1 h before anaesthesia. In all patients, ondansetron 4 mg was administered intravenously at the end of surgery and 12 mg was added to the PCA solution.

MAIN OUTCOME MEASURES

The primary outcome measure was complete response (no PONV and no rescue antiemetics) up to 48 h postoperatively.

RESULTS

There was no difference in the proportion of complete responses to 48 h between the groups (P = 0.05), but in the post-anaesthesia care unit and up to 24 h postoperatively, the proportion was significantly higher in the aprepitant and ondansetron group than in the ondansetron only group (76 vs. 50%, P = 0.004 and 38 vs. 16%, P = 0.011, respectively). In the aprepitant and ondansetron group, the time to first PONV was delayed (P = 0.014) and the incidence of nausea up to 24 h postoperatively was lower (P = 0.014). However, there were no differences in the incidences of retching or vomiting, the severity of nausea, use of rescue antiemetics or the incidence of side-effects.

CONCLUSION

Aprepitant 80 mg orally with ondansetron is effective in suppressing early PONV up to 24 h postoperatively and delays the time to first PONV in patients with fentanyl-based intravenous PCA after gynaecological laparoscopy. However, the combination prophylaxis with aprepitant and ondansetron failed to reach the predefined primary study outcome when compared with ondansetron alone.

TRIAL REGISTRATION

Clinicaltrial.gov identifier: NCT01897337.

Chemotherapy-Induced Delayed Emesis: What is the Role of 5-HT3Antagonists?

Objective:

To review the current literature assessing the efficacy of different antiemetics, with a focus on comparison between serotonin (5-HT3) antagonists and other antiemetics, in the treatment of delayed emesis induced by either cisplatin or non-cisplatin cytotoxic agents.

Data Sources:

A MEDLINE search (1966–July 2002) was performed using delayed emesis, vomiting, nausea, chemotherapy, cisplatin, moderately emetogenic, selective serotonin subtype-3 (5-HT3) receptor antagonists, metoclopramide, domperidone, corticosteroids, dexamethasone, prognostic factors, risk factors, and neurokinin-1 (NK1) receptor antagonists as key words or subject headings. Only English-language articles were identified and included. Additional references were retrieved from selected articles.

Data Synthesis:

Various antiemetic consensus guidelines have recommended the use of different pharmacologic treatment, including the use of 5-HT3antagonists, for the prevention of chemotherapy-induced delayed emesis. In some instances, it has been suggested that combinations containing a 5-HT3antagonist may be superior to others. Current data have been synthesized in an attempt to demonstrate the efficacy of 5-HT3antagonists in the treatment of chemotherapy-induced delayed emesis.

Conclusions:

Dexamethasone has consistently shown its antiemetic efficacy for delayed emesis induced by cisplatin and non-cisplatin agents, whereas the role of 5-HT3antagonists alone remains controversial. Metoclopramide has been shown to be as efficacious as 5-HT3antagonists when combined with dexamethasone for the prevention of delayed emesis. As a result, 5-HT3antagonists should be reserved as second-line agents to metoclopramide in addition to dexamethasone. NK1 receptor antagonists have shown some early promising results. However, many questions need to be addressed before their extensive use in clinical practice.

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.

Comparison of the Control of Nausea and Vomiting among Several Moderately Emetic-Risk Chemotherapy Regimens

BACKGROUND

Different antiemetic medications with or without aprepitant are recommended for moderately emetic-risk chemotherapy (MEC) depending on the emetic potential of chemotherapy agents, although the criterion for the use of aprepitant is still unclear. The present study was designed to compare the control of chemotherapy-induced nausea and vomiting (CINV) among several MEC regimens used in the outpatient chemotherapy setting.

MATERIALS AND METHODS

A single center prospective observational study was carried out in 326 patients who received 2,061 chemotherapy cycles from January 2013 to December 2014. Antiemetic medication consisting of two-drug combination of granisetron (day 1) and dexamethasone (days 1-3) was carried out in 87.6% of patients receiving the first chemotherapy cycle. The checklist for CINV was provided to all patients, and the control of CINV was evaluated on the next visit based on the checklist. Complete inhibition of nausea and vomiting during acute and delayed periods were compared among MEC regimens.

RESULTS

Two hundred and one patients received the first cycle of chemotherapy, in which the rates of complete inhibition of nausea and vomiting were 87.6% and 95.5%, respectively, during acute period, and 68.2% and 92.0%, respectively, during delayed period. There were no significant differences in the control of CINV among oxaliplatin, carboplatin and irinotecan, except for the cyclophosphamide-base regimen.

CONCLUSIONS

Two-drug antiemetic medication of 5-HT3 receptor antagonist and dexamethasone was sufficiently effective for prevention of CINV in most MEC regimens.

Chemotherapy-induced nausea and vomiting: incidence and characteristics of persistent symptoms and future directions NCCTG N08C3 (Alliance)

BACKGROUND

Despite newer agents, chemotherapy-induced nausea and vomiting (CINV) continues to remain a distressing side effect to a proportion of patients undergoing systemic anti-cancer therapy.

METHODS

We recently performed an unplanned secondary analysis on a previously reported negative phase III trial (N08C3) looking at the efficacy of gabapentin/placebo in combination with dexamethasone and a 5HT3 receptor antagonist in the prevention of CINV for 413 patients undergoing regimens with highly emetogenic chemotherapy (HEC). In the current study, we attempted to better understand the higher than expected rate of overall patient satisfaction, despite a low complete response rate in both arms. Additionally, we looked at patient variables and their relationship to rates of CINV.

RESULTS

Approximately one third of patients experienced more than mild nausea and reported scores on the Functional Living Index-Emesis that indicated interference with activities. Thirty-five percent reported nausea greater than 2.5 on a scale of 0 to 10 (0 being none), 19 % reported at least one emetic episode, and 49 % reported taking rescue medication. Nausea and vomiting on day 1, cisplatin therapy, and history of motion sickness significantly predicted delayed CINV. Age, combination chemotherapy (HEC with moderately emetogenic), and getting treatment for breast cancer predicted CINV on day 1.

DISCUSSION

These data confirm previous reports that subgroups of patients may be more prone to acute and delayed CINV. Future CINV study design may benefit from a more individualized approach to CINV management, targeting those patients who are truly at risk for CINV despite continued drug development efforts.

Neuromotor tolerability and behavioural characterisation of cannabidiolic acid, a phytocannabinoid with therapeutic potential for anticipatory nausea

RATIONALE

Anticipatory nausea (AN) is a poorly controlled side effect experienced by chemotherapy patients. Currently, pharmacotherapy is restricted to benzodiazepine anxiolytics, which have limited efficacy, have significant sedative effects and induce dependency. The non-psychoactive phytocannabinoid, cannabidiolic acid (CBDA), has shown considerable efficacy in pre-clinical AN models, however determination of its neuromotor tolerability profile is crucial to justify clinical investigation. Provisional evidence for appetite-stimulating properties also requires detailed investigation.

OBJECTIVES

This study aims to assess the tolerability of CBDA in locomotor activity, motor coordination and muscular strength tests, and additionally for ability to modulate feeding behaviours.

METHODS

Male Lister Hooded rats administered CBDA (0.05-5 mg/kg; p.o.) were assessed in habituated open field (for locomotor activity), static beam and grip strength tests. A further study investigated whether these CBDA doses modulated normal feeding behaviour. Finally, evidence of anxiolytic-like effects in the habituated open field prompted testing of 5 mg/kg CBDA for anxiolytic-like activity in unhabituated open field, light/dark box and novelty-suppressed feeding (NSF) tests.

RESULTS

CBDA had no adverse effects upon performance in any neuromotor tolerability test, however anxiolytic-like behaviour was observed in the habituated open field. Normal feeding behaviours were unaffected by any dose. CBDA (5 mg/kg) abolished the increased feeding latency in the NSF test induced by the 5-HT1AR antagonist, WAY-100,635, indicative of anxiolytic-like effects, but had no effect on anxiety-like behaviour in the novel open field or light/dark box.

CONCLUSIONS

CBDA is very well tolerated and devoid of the sedative side effect profile of benzodiazepines, justifying its clinical investigation as a novel AN treatment.

Chemotherapy for Advanced Non-small Cell Lung Cancer

Non-small cell lung cancer has seen an unprecedented augmentation of therapeutic options over the last couple of years. Improved understanding of molecular drivers and the role of the immune system in cancer therapy have brought new drugs to the armamentarium. Despite these advances, cytotoxic chemotherapy remains a substantial part of therapy for most patients in locally advanced and metastatic stage. Initially thought to be a chemotherapy-resistant entity, meta-analyses in the mid-1990s demonstrated modest efficacy of platinum-based therapy. Further combination trials demonstrated enhanced efficacy for several regimen in first and second lines, including the introduction of antimetabolites, taxanes, and anti-angiogenic agents. Maintenance chemotherapy has been another novel, successful approach for management of metastatic disease. Herein, we summarize the current concepts of chemotherapy, its applicability to the different histologies, and novel concepts of therapy.

Comparative study of preoperative use of oral gabapentin, intravenous dexamethasone and their combination in gynaecological procedure

BACKGROUND

We studied the effects of oral gabapentin and intravenous (I.V.) dexamethasone given together or separately 1 h before the start of surgery on intraoperative hemodynamics Postoperative analgesia and postoperative nausea vomiting (PONV) in patients undergoing gynaecological procedure.

MATERIALS AND METHODS

Patients were randomly divided into three groups: Group 1 (gabapentin, n = 46) received 400 mg gabapentin, Group 2 (dexamethasone, n = 46) received 8 mg dexamethasone and Group 3 (gabapentin plus dexamethasone, n = 46) received both 400 mg gabapentin and 8 mg dexamethasone I.V. 1 h before the start of surgery. Standard induction and maintenance of anesthesia were accomplished. Visual analog scale for pain was recorded for 12 h. Side effects were noted.

RESULTS

Hemodynamics at various time interval (0, 5, 10, 15, 20, 25 and 30 min) of laryngeal mask airway insertion and PONV were found significantly lower in Group 3 than in Group 1 and Group 2 (P < 0.05). The average time to first postoperative analgesic requirement at (visual analogue score >3) was significantly longer in Group 3 (510.00 ± 61.64 min) than in Group 1 (352.83 ± 80.61 min) and in Group 2 (294.78 ± 60.76 min), (P < 0.05).

CONCLUSION

The present study concludes that the combination of oral Gabapentin and I.V. dexamethasone has significantly less hemodynamic changes, better postoperative analgesia and less incidence of PONV than individual administration of each drug.

Defining the efficacy of neurokinin-1 receptor antagonists in controlling chemotherapy-induced nausea and vomiting in different emetogenic settings-a meta-analysis

PURPOSE

This meta-analysis was performed to evaluate the efficacy of neurokinin-1 receptor antagonists (NK1RAs) for the prevention of chemotherapy-induced nausea and vomiting (CINV) across different categories of chemotherapeutic emetogenicity.

METHODS

A systematic review of MEDLINE (via PubMed) and OVID databases, plus major oncology conferences, identified randomized, controlled trials evaluating NK1RAs in combination with a 5-HT3 RA plus a glucocorticoid for management of CINV. Efficacy end points were no emesis, no nausea, and complete response (CR) rates. Data were analyzed using a random effects model.

RESULTS

Twenty-three trials (N = 11,814) were identified. Based on absolute differences (AD) for no emesis (21 %), no nausea (8 %), CR (16 %), and odd ratios (OR) of 2.62, 1.43, and 2.16, respectively, NK1RA regimens provided better CINV protection versus control groups (all p < 0.00001) in patients receiving cisplatin-based highly emetogenic chemotherapy (HEC). In patients receiving anthracycline/cyclophosphamide (AC)-based HEC, respective ADs and ORs were 14, 4, and 11 % and 1.97 (p < 0.0001), 1.17 (p = 0.04), and 1.62 (p < 0.00001). In patients receiving moderately emetogenic chemotherapy (3 trials), no statistically significant benefit of NK1RAs was found; however, positive trends were detected for CR and no emesis. NK1RAs were effective for CINV prevention in a small number of studies using high-dose chemotherapy as conditioning prior to stem cell transplant and cisplatin-based multiple-day chemotherapy (MDC).

CONCLUSIONS

This meta-analysis demonstrated the efficacy of NK1RA in preventing vomiting in patients receiving HEC (including AC), with smaller effects on prevention of nausea. Efficacy is also seen with high-dose chemotherapy and cisplatin-based MDC.

Gabapentin for Postoperative Vomiting in Children Requiring Posterior Fossa Tumor Resection

Gabapentin is well known for its pain control and antiepileptic effect, but its antiemetic effect is poorly investigated. Here we report on effective gabapentin use for refractory vomiting after craniotomy in two children with medulloblastoma in the fourth ventricle. The two pediatric patients (an 11-year-old girl and a 4-year-old boy) underwent near-total excision of the tumor via craniotomy. Both patients suffered from refractory postoperative nausea and vomiting, treated with multiple traditional antiemetic drugs but without relief. After gabapentin intake, their nausea and vomiting improved from one to two episodes per day to complete resolution of symptoms. This report suggests that gabapentin may be a novel antiemetic therapeutic intervention for patients with refractory nausea and vomiting after craniotomy.

Aprepitant in the prevention of vomiting induced by moderately and highly emetogenic chemotherapy

Chemotherapy is a major therapeutic approach for malignant neoplasms; however, due to the most common adverse events of nausea and vomiting, scheduled chemotherapeutic programs may be impeded or even interrupted, which severely impairs the efficacy. Aprepitants, 5-HT3 antagonists and dexamethasone are primary drugs used to prevent chemotherapy-induced nausea and vomiting (CINV). These drugs have excellent efficacy for control of acute vomiting but are relatively ineffective for delayed vomiting. Aprepitant may remedy this deficiency. Substance P was discovered in the 1930s and its association with vomiting was confirmed in the 1950s. This was followed by a period of non-peptide neurokinin-1 (NK-1) receptor antagonist synthesis and investigation in preclinical studies and clinical trials (phases I, II and III). The FDA granted permission for the clinical chemotherapeutic use of aprepitant in 2003. At present, the combined use of aprepitant, 5-HT3 antagonists and dexamethasone satisfactorily controls vomiting but not nausea. Therefore, new therapeutic approaches and drugs are still needed.

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.

Biological and Pharmacological Aspects of the NK1-Receptor

The neurokinin 1 receptor (NK-1R) is the main receptor for the tachykinin family of peptides. Substance P (SP) is the major mammalian ligand and the one with the highest affinity. SP is associated with multiple processes: hematopoiesis, wound healing, microvasculature permeability, neurogenic inflammation, leukocyte trafficking, and cell survival. It is also considered a mitogen, and it has been associated with tumorigenesis and metastasis. Tachykinins and their receptors are widely expressed in various human systems such as the nervous, cardiovascular, genitourinary, and immune system. Particularly, NK-1R is found in the nervous system and in peripheral tissues and are involved in cellular responses such as pain transmission, endocrine and paracrine secretion, vasodilation, and modulation of cell proliferation. It also acts as a neuromodulator contributing to brain homeostasis and to sensory neuronal transmission associated with depression, stress, anxiety, and emesis. NK-1R and SP are present in brain regions involved in the vomiting reflex (the nucleus tractus solitarius and the area postrema). This anatomical localization has led to the successful clinical development of antagonists against NK-1R in the treatment of chemotherapy-induced nausea and vomiting (CINV). The first of these antagonists, aprepitant (oral administration) and fosaprepitant (intravenous administration), are prescribed for high and moderate emesis.

Characterization and Pharmacokinetic Study of Aprepitant Solid Dispersions with Soluplus®

Solid dispersions are a useful approach to improve the dissolution rate and bioavailability of poorly water-soluble active pharmaceutical ingredients (APIs). The aim of this study was to improve the physicochemical properties and bioavailability of a poorly water-soluble aprepitant by preparation of solid dispersions. The solid dispersions were characterized by dissolution, FTIR, XRPD, DSC, SEM and pharmacokinetic studies in rats. The dissolution rate of the aprepitant was significantly increased by solid dispersions, and XRD, DSC, and SEM analysis indicated that the aprepitant existed in an amorphous form within the solid dispersions. The result of dissolution study showed that the dissolution rate of SDs was nearly five-fold faster than aprepitant. FTIR spectrometry suggested the presence of intermolecular hydrogen bonds between the aprepitant and polymer. Pharmacokinetic studies in rats indicated that the degree drug absorption was comparable with that of Emend^®. Aprepitant exists in an amorphous state in solid dispersions and the solid dispersions can markedly improve the dissolution and oral bioavailability of the aprepitant. The AUC_0–t of the SDs was 2.4-fold that of the aprepitant. In addition, the method and its associated techniques are very easy to carry out.

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.

Neuropeptides: metabolism to bioactive fragments and the pharmacology of their receptors

The proteolytic processing of neuropeptides has an important regulatory function and the peptide fragments resulting from the enzymatic degradation often exert essential physiological roles. The proteolytic processing generates, not only biologically inactive fragments, but also bioactive fragments that modulate or even counteract the response of their parent peptides. Frequently, these peptide fragments interact with receptors that are not recognized by the parent peptides. This review discusses tachykinins, opioid peptides, angiotensins, bradykinins, and neuropeptide Y that are present in the central nervous system and their processing to bioactive degradation products. These well-known neuropeptide systems have been selected since they provide illustrative examples that proteolytic degradation of parent peptides can lead to bioactive metabolites with different biological activities as compared to their parent peptides. For example, substance P, dynorphin A, angiotensin I and II, bradykinin, and neuropeptide Y are all degraded to bioactive fragments with pharmacological profiles that differ considerably from those of the parent peptides. The review discusses a selection of the large number of drug-like molecules that act as agonists or antagonists at receptors of neuropeptides. It focuses in particular on the efforts to identify selective drug-like agonists and antagonists mimicking the effects of the endogenous peptide fragments formed. As exemplified in this review, many common neuropeptides are degraded to a variety of smaller fragments but many of the fragments generated have not yet been examined in detail with regard to their potential biological activities. Since these bioactive fragments contain a small number of amino acid residues, they provide an ideal starting point for the development of drug-like substances with ability to mimic the effects of the degradation products. Thus, these substances could provide a rich source of new pharmaceuticals. However, as discussed herein relatively few examples have so far been disclosed of successful attempts to create bioavailable, drug-like agonists or antagonists, starting from the structure of endogenous peptide fragments and applying procedures relying on stepwise manipulations and simplifications of the peptide structures.

Aprepitant and fosaprepitant: a 10-year review of efficacy and safety

Chemotherapy-induced nausea and vomiting (CINV) is a common adverse event associated with anticancer treatment that can have a significant adverse impact on patient health-related quality of life and that can potentially undermine the effectiveness of chemotherapy. Traditional regimens to prevent CINV generally involved a combination of a corticosteroid plus a 5-hydroxytryptamine (5HT3) receptor antagonist (RA). In the past 10 years, antiemetic treatment has greatly advanced with the availability of the neurokinin-1 receptor antagonist (NK1 RA) aprepitant and its prodrug fosaprepitant. NK1 RAs have a different mechanism of action in CINV than corticosteroids and 5HT3 RAs, thus their use can complement traditional antiemetic drugs and can enhance control of CINV. This review examined accumulated data regarding the safety and efficacy of aprepitant and fosaprepitant over the decade since the first regulatory approval. Data from key studies of aprepitant and fosaprepitant in the prevention of CINV in patients receiving moderately and highly emetogenic chemotherapy were explored, as were recommendations in currently available guidelines for their use. In addition, their use as antiemetic therapy in special patient populations was highlighted. Future perspectives on potential uses of aprepitant and fosaprepitant for indications other than CINV are presented.

Phase III double-blind, placebo-controlled study of gabapentin for the prevention of delayed chemotherapy-induced nausea and vomiting in patients receiving highly emetogenic chemotherapy, NCCTG N08C3 (Alliance)

BACKGROUND

Despite targeted antiemetics, data support an unmet need related to the management of delayed nausea and vomiting (NV). Promising pilot data informed this phase III trial evaluating gabapentin for delayed NV from highly emetogenic chemotherapy (HEC).

METHODS

Participants were randomized to receive prophylactic treatment with 20 mg of dexamethasone and a 5HT3 receptor antagonist (RA) on the day of chemotherapy, followed by gabapentin 300 mg twice a day and dexamethasone (dex) or placebo and dex after HEC. Gabapentin/placebo was started the day of chemotherapy and continued through day 5 for the first chemotherapy cycle, whereas dex was titrated down on days 2-4. The primary end point was complete response (CR), defined as no emesis and no use of rescue medications on days 2-6, using an NV diary. The percentages of those in each group with a CR were compared by Fisher's exact test.

RESULTS

Four hundred thirty patients were enrolled in this study. Forty-seven percent of patients in the gabapentin arm and 41% in the placebo arm had a CR (P = .23). Mean number of emesis episodes was <0.5 daily, and mean nausea severity was < 2 (mild). In both arms, patient satisfaction with NV control was greater than 8 (with 10 being perfectly satisfied). There were no significant differences in unwanted side effects.

CONCLUSIONS

In this study, gabapentin did not significantly improve delayed NV. Patients were satisfied with the control of their nausea and vomiting irrespective of arm. The use of a 5HT3 RA and dexamethasone provided good control of nausea and vomiting for most patients.

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.

Carbamazepine for prevention of chemotherapy-induced nausea and vomiting: a pilot study

CONTEXT AND OBJECTIVE

Nausea and vomiting are major inconveniences for patients undergoing chemotherapy. Despite standard preventive treatment, chemotherapy-induced nausea and vomiting (CINV) still occurs in approximately 50% of these patients. In an attempt to optimize this treatment, we evaluated the possible effects of carbamazepine for prevention of CINV.

DESIGN AND LOCATION

Prospective nonrandomized open-label phase II study carried out at a Brazilian public oncology service.

METHODS

Patients allocated for their first cycle of highly emetogenic chemotherapy were continuously recruited. In addition to standard antiemetic protocol that was made available, they received carbamazepine orally, with staggered doses, from the third day before until the fifth day after chemotherapy. Considering the sparseness of evidence about the efficacy of anticonvulsants for CINV prevention, we used Simon's two-stage design, in which 43 patients should be included unless overall complete prevention was not achieved in 9 out of the first 15 entries. The Functional Living Index-Emesis questionnaire was used to measure the impact on quality of life.

RESULTS

None of the ten patients (0%) presented overall complete prevention. In three cases, carbamazepine therapy was withdrawn because of somnolence and vomiting before chemotherapy. Seven were able to take the medication for the entire period and none were responsive, so the study was closed. There was no impact on the patients' quality of life.

CONCLUSION

Carbamazepine was not effective for prevention of CINV and also had a deleterious side-effect profile in this population.