Single-blind study of the effects of intravenous dolasetron mesylate versus ondansetron on electrocardiographic parameters in normal volunteers

Isopropyl alcohol inhalation versus 5-HT3 antagonists for treatment of nausea: a meta-analysis of randomised controlled trials

PURPOSE

Nausea is a common and unpleasant sensation for which current therapies such as serotonin (5-HT3) antagonists are often ineffective, while also conferring a risk of potential adverse events. Isopropyl alcohol (IPA) has been proposed as a treatment for nausea. We aimed to compare IPA with 5-HT3 antagonists for the treatment of nausea across all clinical settings.

METHODS

MEDLINE, EMBASE, PubMed, CENTRAL and CINAHL were searched from inception to 17 July 2023 for randomised controlled trials (RCTs) comparing inhaled IPA and a 5-HT3 antagonist for treatment of nausea. Severity and duration of nausea, rescue antiemetic use, adverse events and patient satisfaction were the outcomes sought. Risk of bias (RoB) was assessed using Cochrane RoB 2. Random-effects model was used for meta-analysis. Combination of meta-analyses and narrative review was used to synthesise findings. The evidence was appraised using GRADE.

RESULTS

From 1242 records, 4 RCTs were included with 382 participants. Participants receiving IPA had a significantly lower mean time to 50% reduction in nausea (MD - 20.06; 95% CI - 26.26, - 13.85). Nausea score reduction at 30 min was significantly greater in the IPA group (MD 21.47; 95% CI 15.47, 27.47). IPA led to significantly reduced requirement for rescue antiemetics (OR 0.60; 95% CI 0.37, 0.95; p = 0.03). IPA led to no significant difference in patient satisfaction when compared with a 5-HT3 antagonist. The overall GRADE assessment of evidence quality ranged from very low to low.

CONCLUSION

IPA may provide rapid, effective relief of nausea when compared with 5-HT3 antagonists.

The Risk of QTc Prolongation with Antiemetics in the Palliative Care Setting: A Narrative Review

Nausea and vomiting are common within the palliative care population. Antiemetic agents may help control symptoms, but may also place patients at risk for QTc prolongation. This article reviews pharmacotherapy agents including anticholinergics, antihistamines, antidopaminergics, 5-HT3 receptor antagonists, dronabinol, and medical marijuana and their associated risk of QTc prolongation. A clinical treatment pathway is provided to help guide clinicians in choosing the most appropriate antiemetic based upon patient specific factors for QTc prolongation.

The KCa2 Channel Inhibitor AP14145, But Not Dofetilide or Ondansetron, Provides Functional Atrial Selectivity in Guinea Pig Hearts

Background and Purpose: Prolongation of cardiac action potentials is considered antiarrhythmic in the atria but can be proarrhythmic in ventricles if the current carried by Kv11.1-channels (I_Kr) is inhibited. The current mediated by K_Ca2-channels, I_KCa, is considered a promising new target for treatment of atrial fibrillation (AF). Selective inhibitors of I_Kr (dofetilide) and I_KCa (AP14145) were used to compare the effects on ventricular and atrial repolarization. Ondansetron, which has been reported to be a potent blocker of both I_Kr and I_KCa, was included to examine its potential atrial antiarrhythmic properties. Experimental Approach: The expression of K_Ca2- and K_v11.1-channels in the guinea pig heart was investigated using quantitative polymerase chain reaction (qPCR). Whole-cell patch clamp technique was used to investigate the effects of dofetilide, AP14145, and ondansetron on I_KCa and/or I_Kr. The effect of dofetilide, AP14145, and ondansetron on atrial and ventricular repolarization was investigated in isolated hearts. A novel atrial paced in vivo guinea pig model was further validated using AP14145 and dofetilide. Key Results: AP14145 increased the atrial effective refractory period (AERP) without prolonging the QT interval with Bazett's correction for heart rate (QTcB) both ex vivo and in vivo. In contrast, dofetilide increased QTcB and, to a lesser extent, AERP in isolated hearts and prolonged QTcB with no effects on AERP in the in vivo guinea pig model. Ondansetron did not inhibit I_KCa, but did inhibit I_Kr in vitro. Ondansetron prolonged ventricular, but not atrial repolarization ex vivo. Conclusion and Implications: I_KCa inhibition by AP14145 selectively increases atrial repolarization, whereas I_Kr inhibition by dofetilide and ondansetron increases ventricular repolarization to a larger extent than atrial repolarization.

High-dose ondansetron reduces activation of interoceptive and sensorimotor brain regions

Several psychiatric disorders involve abnormalities of interoception and associated neural circuitry centered on the insula. The development of interventions modulating interoceptive circuits could lead to novel treatment approaches for these disorders. The 5-HT3 receptor antagonist ondansetron is a good candidate for the modulation of interoceptive circuits, as 5-HT3 receptors are located abundantly on sensory pathways and ondansetron has shown some clinical utility in disorders characterized by sensory and interoceptive abnormalities. The present study tested the ability of three different doses of ondansetron to engage neural regions involved in interoception to determine the drug's utility as a therapeutic agent to target circuit abnormalities in patients. Fifty-three healthy subjects were randomized to receive a single 8-mg (n = 18), 16-mg (n = 17), or 24-mg (n = 18) dose of ondansetron and placebo before MRI scanning on separate days. Subjects performed an fMRI task previously shown to engage interoceptive circuitry in which they viewed videos depicting body movements/sensation and control videos. The results revealed a highly significant relationship between dosage and activation in bilateral insula, somatosensory and premotor regions, cingulate cortex, and temporal cortex for control but not body-focused videos. These effects were driven by a robust reduction in activation for ondansetron compared to placebo for the 24-mg group, with weaker effects for the 16-mg and 8-mg groups. In conclusion, high-dose ondansetron reduces activation of several areas important for interoception, including insula and sensorimotor cortical regions. This study reveals the potential utility of this drug in modulating hyperactivity in these regions in patients.

What is new in the battle against postoperative nausea and vomiting?

The issue of postoperative nausea and vomiting (PONV) still poses a significant burden on our patients. Although rarely associated with a life-threatening condition, it is consistently considered as one of the most undesirable side effects of surgery and anesthesia. There are well-established risk factors for the development of PONV that include patient-related factors, anesthetic technique, use of volatile anesthetics, use of nitrous oxide, duration of anesthesia, opioid administration, and type of surgery. Because pharmacologic interventions for PONV are not without risks, practitioners must assess patient's risk status from low to high and consider the benefits of treatment. This review summarizes the current state of knowledge related to PONV and provides a practical approach toward risk assessment, prevention, and numerous treatment strategies.

Effect of Intravenous Ondansetron on the QT Interval of Patients' Electrocardiograms

OBJECTIVE

Ondansetron improves the success of oral rehydration in children with gastroenteritis. In postoperative adults, ondansetron has been shown to prolong the corrected QT (QTc). The aim of the study was to evaluate the effect of ondansetron on the QT at peak effect and at 1-hour postpeak effect in pediatric patients.

METHODS

This was an observational study looking at patients aged 6 months to 18 years receiving intravenous ondansetron for nausea, vomiting, or the inability to take fluids in the emergency department. Patients had electrocardiogram performed at baseline, at ondansetron's peak effect, and 1 hour postpeak effect. A paired samples Student t test compared QTc change at peak effect to zero. Peak effect of intravenous ondansetron is 3 minutes.

RESULTS

One hundred patients were included. Fifty-five percent of patients were female with a mean age of 8.3 years. The mean (range) baseline QTc was 435 (388 to 501) milliseconds. The mean (range) change in QTc at peak effect of ondansetron was 3 (-40 to 65) milliseconds (P = 0.072). The change in QTc 1-hour postpeak effect of ondansetron was 3 (-43 to 45) milliseconds (P = 0.082). No change at peak effect or 1-hour postpeak effect was clinically significant.

CONCLUSIONS

Ondansetron does not affect the QTc of pediatric patients receiving the medication for nausea, vomiting, or inability to take fluids in the emergency department. No changes in the QTc are clinically significant. To date, there have been no studies evaluating the effect of ondansetron in this acutely ill population; therefore, a larger study should be completed to confirm these data.

Frequency, characteristics and risk factors of QT interval prolonging drugs and drug-drug interactions in cancer patients: a multicenter study

Background

Cancer patients may receive a high number of medications with the potential to prolong QT interval and subsequent TdP (torsades de pointes). This study aimed to identify the prevalence of QT prolonging drugs, their TdP risk, QT prolonging drug-drug interactions (QT-DDIs), levels, predictors, and TdP risk of drugs involved in QT-DDIs.

Methods

This multicenter study included cancer patients from three major tertiary care hospitals of Khyber-Pakhtunkhwa, Pakistan. Micromedex DrugReax® was used for identification of QT-DDIs. TdP risks were identified by AZCERT (Arizona Center for Education and Research on Therapeutics) classification. Logistic regression analysis was performed to identify predictors of QT-DDIs.

Results

Of 555 patients, 51% were females. Mean age was 46.9 ± 15.7 years. Total 28 distinct QT prolonging drugs were identified in 92.6% of the patients. Overall 21.8% patients were presented with QT-DDIs. Of total 288 identified QT-DDIs, all were of major-severity and fair-documentation. According to AZCERT classification, 59.9% of the interacting drugs were included in list-1 (known risk of TdP), 4.7% in list-2 (possible risk of TdP) and 6.8% in list-3 (conditional risk of TdP). Univariate logistic regression analysis showed significant results for various predictors such as, 8–9 prescribed medications (p < 0.001) and ≥10 medications (p < 0.001), 2 QT drugs (p < 0.001) and ≥3 QT drugs (p < 0.001), breast cancer (p = 0.03), gastrointestinal cancer (p = 0.03), 4–5 supportive care drugs (p < 0.001), 6–8 supportive care drugs (p < 0.001) and >8 supportive care drugs (p < 0.001).

Conclusions

A high prevalence of QT prolonging drugs and QT-DDIs was reported in oncology. Appropriate precautions are needed to prevent harmful consequences of these interactions.

Electronic supplementary material

The online version of this article (10.1186/s40360-017-0181-2) contains supplementary material, which is available to authorized users.

Pharmacology of Antiemetics: Update and Current Considerations in Anesthesia Practice

Postoperative nausea and vomiting (PONV) is associated with delayed recovery and dissatisfaction after surgical procedures. A key component to management is identifying risk factors and high-risk populations. Advances in pharmacologic therapeutics have resulted in agents targeting different pathways associated with the mediation of nausea and vomiting. This review focuses on these agents and the clinical aspects of their use in patients postoperatively. Combination therapies are reviewed, and studies demonstrate that when 2 or more antiemetic agents acting on different receptors are used, an overall improved efficacy is demonstrated when compared with a single agent alone in patients.

Torsades de Pointes after Ondansetron Infusion in 2 Patients

Drugs that prolong the electrocardiographic QT interval increase the risk of ventricular arrhythmias, particularly torsades de pointes. Ondansetron, a 5-hydroxytryptamine type 3 receptor antagonist antiemetic, is one such drug. We present the cases of 2 patients who were given intravenous ondansetron and subsequently developed torsades de pointes. Both had normal QT intervals at baseline but were discovered to have risk factors that predisposed them to drug-induced QT prolongation and ventricular arrhythmias. We briefly review the mechanisms for torsades de pointes caused by QT-prolonging medications, describe characteristics that increase patients' susceptibility to drug-induced QT prolongation, and call attention to the risk of ventricular arrhythmias in patients who are given ondansetron.

Comparative Pharmacology and Guide to the Use of the Serotonin 5-HT3 Receptor Antagonists for Postoperative Nausea and Vomiting

Since the introduction of the serotonin 5-hydroxy tryptamine 3 (5-HT₃) receptor antagonists in the early 1990s, the incidence of postoperative nausea and vomiting (PONV) and post-discharge nausea and vomiting (PDNV) has decreased, yet continues to be a problem for the surgical patient. The clinical application of the 5-HT₃ receptor antagonists has helped define the approach and role of these antiemetics in the prevention and treatment of PONV and PDNV. Pharmacological and clinical differences exist among these medications resulting in corresponding differences in effectiveness, safety, optimal dosage, time of administration, and use as combination and rescue antiemetic therapy. The clinical application of the 5-HT₃ receptor antagonist antiemetics has improved the prevention and treatment of PONV and PDNV. The most recent consensus guidelines for PONV published in 2014 outline the use of these antiemetics. The 5-HT₃ receptor antagonists play an important role to help prevent PONV and PDNV in perioperative care pathways such as Enhanced Recovery After Surgery (ERAS). Comparisons and guidelines for use of the 5-HT₃ receptor antagonists in relation to the risk for PONV and PDNV are reviewed.

A review of dolasetron as management of nausea and vomiting in cancer patients

Objective. To systematically review the literature about the pharmacology, pharmacokinetics, efficacy, dosing, and adverse effects of dolasetron, and to define its role in the management of chemotherapy-and radiation-induced nausea and vomiting.

Data Synthesis. A MedLine search was conducted using 5-HT3-receptor antagonists, antiemetics, chemotherapy toxicity, dolasetron, emesis, nausea, and vomiting as search terms. Reference lists and bibliographies of pertinent articles were also identified and reviewed. Both preclinical and clinical literature were reviewed and analyzed.

Data Synthesis. Dolasetron is a serotonin type 3 (5-HT3)-receptor antagonist with potent antiemetic effects in the management of nausea and vomiting. Following administration, dolasetron is rapidly converted to hydrodolasetron, which is believed to be responsible for the drug's antiemetic activity. Results of multiple studies have demonstrated the efficacy of this agent in the prevention of chemotherapy-induced emesis, including that induced by cisplatin. As a single agent, dolasetron produces a complete response rate (RR) in 44% to 57% of patients treated with cisplatin (≥70 mg/m2) and in 59% to 80% of patients treated with moderately emetogenic chemotherapy, such as cyclophosphamide, methotrexate, and fluorouracil (CMF) therapy. When combined with dexamethasone, the RRs are increased. Dolasetron is well tolerated, with headache (24%) and diarrhea (12%) the most commonly reported adverse effects. The efficacy and safety of dolasetron are comparable to those observed with other 5-HT3-receptor antagonists. According to four recently published clinical practice guidelines for use of antiemetics, dolasetron is an appropriate first-line option for the prevention of nausea and vomiting due to moderately to highly emetogenic chemotherapy. Further clinical trials will determine the optimal dose and the role of this highly effective antiemetic agent for other purposes, such as treatment of delayed emesis and emesis resulting from radiation therapy and high-dose chemotherapy followed by bone marrow transplantation.

Local-anesthetic like inhibition of the cardiac sodium channel Nav1.5 α-subunit by 5-HT3 receptor antagonists

5-hydroxytryptamine 3 receptor (5-HT3 receptor) antagonists are administered for prevention and therapy of nausea and vomiting. Although regarded as safe therapeutics, they can also provoke arrhythmias by prolonging the QRS interval. However, the mechanisms mediating this cardiotoxicity are poorly understood. Here we investigated effects of 5-HT3 receptor antagonists on the cardiac Na(+) channel Nav1.5. We explored the interaction of dolasetron, tropisetron, granisetron and ondansetron on the human α-subunit Nav1.5 heterologously expressed in HEK293 cells. Sodium currents were explored by means of whole-cell patch clamp recordings. All four substances inhibited the Nav1.5 in a concentration and state-dependent manner. Dolasetron displayed the lowest blocking efficacy, and tropisetron was the most potent blocker with a half maximum blocking concentration of 18µM for tonic block of inactivated channels. Tropisetron was also the most potent use-dependent inhibitor, and it also induced a strong open -channel block. Both tonic and use-dependent block by tropisetron were abbreviated on the local-anesthetic insensitive mutant Nav1.5-F1760A. Co-administration of tropisetron and the local anesthetic bupivacaine or the hypnotic propofol augmented inhibition of Nav1.5. Our data demonstrate that 5-HT3 receptor antagonists induce a local-anesthetic like inhibition of Nav1.5, and that they display different blocking efficacies. Reports on a relevant cardiotoxicity of dolasetron as opposed to other 5-HT3 receptor antagonists do not seem to correlate with a block of Nav1.5. As inhibition of Nav1.5 was enhanced by propofol and bupivacaine however, it is possible that a combined administration of Na(+) channel blockers and 5-HT3 receptor antagonists can provoke arrhythmias.

Cardiotoxicity of antiemetic drugs in oncology: An overview of the current state of the art

PURPOSE

Cardiac complications in cancer patients have been a significant medical problem in the last few years. Cardiosafety profile of most novel approved drugs, in cancer patients, is required by regulatory authorities. Risk of proarrhythmic effect associated with a new drug, in fact, is usually evaluated with specific studies conducted in agreement with ICHE14 guidelines. In this overview, we detailed the cardio safety profile of antiemetic drugs. In particular, we focused on data of 5HT3-RA drugs used for prevention of chemotherapy-induced nausea and vomiting in the oncology setting.

METHODS

A literature search was conducted using the PubMed database to identify studies reporting arrhythmic complications of antiemetic drug used in oncology.

RESULTS AND CONCLUSION

Most of the antiemetic drugs have been approved by regulatory authorities when ICHE14 guidelines were not issued, so the cardiotoxicity of those drugs has been defined with the post-marketing authorization pharmacovigilance activity. We reviewed the cardiotoxicity data of major antiemetic and adjuvant agents, providing a general overview and recommendations about their use in medical oncology.

Intravenous Ondansetron and the QT Interval in Adult Emergency Department Patients: An Observational Study

OBJECTIVES

Ondansetron is known to cause QT interval prolongation, but this effect and clinical significance has not been prospectively studied in adult emergency department (ED) patients. The primary objective was to determine the mean maximal corrected QT interval (QTc) prolongation after intravenous (IV) administration of 4 mg of ondansetron. The secondary objective was to report any serious adverse cardiac electrical events.

METHODS

This was a prospective, observational, single-center cohort study conducted between 2012 and 2013 in an academic, military hospital ED. Adult patients ordered to receive 4 mg of IV ondansetron were eligible for the study. A six-lead electrocardiogram was recorded at baseline and every 2 minutes after ondansetron administration for 20 minutes. The QTc was calculated using the Bazett formula. Serious adverse cardiac electrical events (nonsinus rhythm, severe bradycardia, and sudden cardiac death) were also recorded.

RESULTS

Twenty-two adult ED patients were enrolled. Ondansetron caused a mean prolongation of the QTc by 20 ms (95% confidence interval [CI] = 14 to 26 ms), with a mean proportion change from baseline of 5.2% (95% CI = 3.8% to 6.6%). There were zero (95% CI = 0 to 13%) reported serious adverse cardiac electrical events.

CONCLUSIONS

While QTc prolongation does occur in adult ED patients receiving IV ondansetron, the clinical impact is questionable.

Effect of single doses of IV palonosetron, up to 2.25 mg, on the QTc interval duration: a double-blind, randomized, parallel group study in healthy volunteers

PURPOSE

The use of serotonin type 3 (5-HT3) receptor antagonists (RAs) in the prevention of nausea and vomiting caused by emetogenic chemotherapy is part of a comprehensive management strategy for patients undergoing chemotherapy. Electrocardiographic effects have been reported in patients after intravenous administration of 5-HT3 RAs. The present study investigated the electrocardiogram (ECG) profile of the 5-HT3 RA palonosetron following International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) E14 Guidelines.

METHODS

A total of 221 healthy subjects (101 females, 120 males) were randomized in this phase I, double-blind, double-dummy, parallel group study and assigned to one of five treatments: placebo, palonosetron (0.25, 0.75, or 2.25 mg), or moxifloxacin (400 mg). ECGs were recorded for 24 h pre-dosing until 48 h post-dose. The primary endpoint was the placebo time-matched and baseline-subtracted individual QTc interval prolongation (ΔΔQTcI).

RESULTS

The QTc interval was not prolonged after administration of palonosetron (ΔΔQTcI upper confidence interval was <10 ms for all time points in all palonosetron treatment groups). Assay sensitivity was confirmed with the expected change in the QTc interval after administration of the positive control moxifloxacin.

CONCLUSIONS

Palonosetron, even at supratherapeutic doses, has no effect on cardiac repolarization as measured by the QTc interval in a validated controlled clinical trial.

Deletion of the Serotonin Receptor Type 3A in Mice Leads to Sudden Cardiac Death During Pregnancy

BACKGROUND

The serotonin receptor type 3 (Htr3) blocker is associated with QT prolongation and torsades de pointes. However, little is known about effects of Htr3 on the heart arrhythmia.

METHODS AND RESULTS

An electrophysiological study Involving knock-out (KO) female mice lacking functional Htr3a (Htr3a(-/-)) and their wild-type littermates during non-pregancy (NP) and late pregnancy (LP) was performed. Htr3a mRNA was present in the wild-type, but not in the Htr3a(-/-)mouse hearts. Serotonin and tryptophan hydroxylase 1 (Tph1), a rate-limiting enzyme of serotonin synthesis in hearts, is increased during pregnancy. The heart weight and size were increased in the pregnant mice regardless of a mutation. The QTc intervals were prolonged after pregnancy in both the wild (NP: 171.2±16.8 vs. LP: 247.7±14.3 ms; P<0.001) and Htr3a(-/-)mice (NP: 187.9±18.7 vs. LP: 275.6±11.0 ms, P<0.001). Compared with wild-type LP mice, Htr3a(-/-)LP mice had increased spontaneous ventricle tarchycardia (VT; 56% vs. 0%, P=0.002), VT inducibility (66% vs. 25%, P=0.002) and mortality (56% vs. 0%, P=0.002). Pharmacologic administration of serotonin and Htr3 agonists (m-CPBG) decreased the QT interval in wild mice, but not in Htr3a(-/-)mice.

CONCLUSIONS

Htr3a is present in mouse hearts. Serotonin and Tph1 were increased during pregnancy. The deletion of Htr3a was related to fatal arrhythmias and sudden cardiac death during pregnancy, and its activation reversed the QT prolongation.

Effects of Palonosetron on Perioperative Cardiovascular Complications in Patients Undergoing Noncardiac Surgery With General Anesthesia: A Retrospective Cohort Study

We retrospectively investigated whether palonosetron administered during the induction of general anesthesia is associated with an increased risk of perioperative cardiovascular complications in a single tertiary center cohort consisting of 4,517 palonosetron-exposed patients and 4,517 propensity score-matched patients without palonosetron exposure. The primary endpoint was a composite of perioperative cardiovascular complications, including intraoperative cardiac arrhythmia, intraoperative cardiac death, and myocardial injury within the first postoperative week, and there was no significant difference between the groups (odds ratio [OR] = 1.04; 95% confidence interval [CI] = 0.92-1.19). As secondary endpoints, intraoperative cardioversion, cardiac compression, use of cardiovascular drugs, postoperative hospital stay, and in-hospital mortality showed no differences between the groups. However, the palonosetron group showed decreased intraoperative hypotension (OR = 0.88; 95% CI = 0.79-0.97) and length of postoperative intensive care unit (ICU) stay (4.26 ± 9.86 vs. 6.14 ± 16.75; P = 0.026). Palonosetron did not increase the rate of perioperative cardiovascular complications, and can therefore be used safely during anesthetic induction.

Effects of combined netupitant and palonosetron (NEPA), a cancer supportive care antiemetic, on the ECG of healthy subjects: an ICH E14 thorough QT trial

Chemotherapy-induced nausea and vomiting is ranked among the worst side effects of chemotherapy. NEPA is an oral fixed-dose combination antiemetic under development, consisting of netupitant 300 mg, a highly selective NK₁ receptor antagonist (RA), and palonosetron 0.5 mg, a pharmacologically and clinically distinct 5-HT₃ RA. Although palonosetron is not associated with relevant ECG effects, this study evaluated cardiovascular safety of netupitant in combination with palonosetron, as well as its tolerability.

This randomised, placebo- and positively controlled study in 197 subjects included 4 treatment groups: placebo, 200 mg netupitant + 0.5 mg palonosetron (NEPA_200/0.5), 600 mg netupitant + 1.5 mg palonosetron (NEPA_600/1.5, a supratherapeutic dose), and 400 mg moxifloxacin. Assessments included a 24-h baseline ECG recording, followed by a single dose of treatment and ECG measurements for 2 days.

Mean placebo-corrected time-averaged changes from baseline were similar in NEPA_200/0.5 and NEPA_600/1.5 groups primarily for individually heart rate-corrected QT interval (QTcI: +4.7 and +3.6 ms, respectively) and for heart rate (HR: –3.3 bpm and –3.0 bpm), PR interval (–0.4 ms and 0.2 ms), and QRS interval (1 ms and 0.5 ms). The time-matched analysis showed no upper confidence interval >10 ms, with no suggestion of a QTc effect by pharmacokinetic-pharmacodynamic modeling for parent/metabolites. Moxifloxacin showed the expected placebo-corrected change from baseline (+8.4 ms time average) and the expected profile to establish assay sensitivity. No new morphologic changes of clinical relevance were observed. Treatment-related adverse events were comparable among groups.

This study showed that NEPA treatments produced no significant effects on QTcI, HR, PR interval, QRS interval, and cardiac morphology relative to placebo, even at supratherapeutic doses.

Pooled analysis of phase III clinical studies of palonosetron versus ondansetron, dolasetron, and granisetron in the prevention of chemotherapy-induced nausea and vomiting (CINV)

Purpose

Preventing chemotherapy-induced nausea and vomiting (CINV) is integral to treatment success in patients with cancer. This analysis was undertaken to assess the relative efficacy and safety of palonosetron versus older 5HT₃ RAs in preventing CINV associated with moderately or highly emetogenic chemotherapy.

Methods

Patient-level data from four randomized, double-blind, phase III trials comparing palonosetron 0.25 or 0.75 mg with ondansetron 32 mg, dolasetron 100 mg, or granisetron 40 μg/kg were analyzed. Endpoints included complete response (CR: no emesis and no rescue antiemetics) in the acute (0–24 h), delayed (>24–120 h), and overall (0–120 h) postchemotherapy periods (primary), complete control (CC: no emesis, no rescue antiemetics, and no more than mild nausea), number of emetic episodes, and nausea severity.

Results

CR rates were significantly higher for palonosetron (n = 1,787) versus older 5HT₃ RAs (n = 1,175) in the delayed (57 vs 45 %, P < 0.0001) and overall periods (51 vs 40 %, P < 0.0001); odds ratios (95 % CI) in the acute, delayed, and overall periods were 1.15 (0.98–1.34), 1.62 (1.40–1.88), and 1.56 (1.34–1.81), respectively. Significant differences in CC rates and nausea severity were observed for the delayed and overall periods and in emetic episodes for all three periods. The incidence of treatment-related adverse events was similar with palonosetron (0.25 mg, 20.0 %; 0.75 mg, 26.5 %) and older 5HT₃ RAs (27.5 %).

Conclusions

Palonosetron is more effective than older 5HT₃ RAs for controlling CINV in the delayed and overall postchemotherapy periods.

Treatment of chemotherapy-induced nausea and vomiting

BACKGROUND

Recent improvements in medical oncology include both development of anticancer and supportive therapy. Serotonin receptor antagonists were introduced in clinical practice 20 years ago. Since then, the prevention and treatment of chemotherapy-induced nausea and vomiting allows continuing efficacious chemotherapy that earlier had to be stopped sometimes for intolerance.

AIM

This anniversary review summarises the current antiemetic arsenal focussing on the most potent antiemetic drugs such as serotonin and substance P receptor antagonists.

RESULT

Antiemetic treatment improves quality of life under chemotherapy and contributes to the survival benefit as well. In spite of the use of these new drugs, a significant number of patients still experience nausea and vomiting. Special complications like delayed emesis can be alleviated by combination therapies.

CONCLUSION

Prevention and optimal management of chemotherapy-induced nausea and vomiting should be a goal for most patients receiving emetogenic chemotherapy.

Comparative electrocardiographic effects of intravenous ondansetron and granisetron in patients undergoing surgery for carcinoma breast: A prospective single-blind randomised trial

Background:

Postoperative nausea and vomiting (PONV) are common and distressing symptoms after surgery performed under general anaesthesia. 5-hydroxytryptamine₃ antagonists are routinely used for prevention and treatment of PONV. The aim of our study was to compare the incidence of QTc prolongation and quantify the amount of QTc prolongation with ondansetron and granisetron.

Methods:

This prospective, randomised, single-blind study was carried out in the OT and Recovery Room (RR) of a tertiary referral cancer centre. After obtaining Institutional Review Board approval and written informed consent from the patients, 70 patients undergoing elective surgery for carcinoma breast were included. In the RR, patients randomly received 8 mg of ondansetron or 1 mg of granisetron intravenously. Serial ECGs were recorded at various intervals, Non-invasive blood pressure and SpO₂ were also recorded. Chi-square test and Mann-Whiteny test were used for statistical analysis.

Results:

The demographics were similar in both groups. The incidence of significant QTc prolongation was significantly higher in the ondansetron group (22 of 37 (59.4%) vs. 11 of 33 patients (33.33%) (P<0.05)). There was an increase in the QTc interval in both the groups as compared to the baseline. The median prolongation in QTc interval from baseline was much more in the ondansetron group; this was statistically significant only at 5 and 15 min.

Conclusion:

Granisetron may be a safer option than ondanasetron for prevention and treatment of PONV due to lesser prolongation QTc interval. (ClinicalTrials.gov ID: NCT01352130)

The evaluation and management of drug effects on cardiac conduction (PR and QRS intervals) in clinical development

Recent advances in electrocardiographic monitoring and waveform analysis have significantly improved the ability to detect drug-induced changes in cardiac repolarization manifested as changes in the QT/corrected QT interval. These advances have also improved the ability to detect drug-induced changes in cardiac conduction. This White Paper summarizes current opinion, reached by consensus among experts at the Cardiac Safety Research Consortium, on the assessment of electrocardiogram-based safety measurements of the PR and QRS intervals, representing atrioventricular and ventricular conduction, respectively, during drug development.

Lack of Effect of Aprepitant on Hydrodolasetron Pharmacokinetics in CYP2D6 Extensive and Poor Metabolizers

To prevent chemotherapy-induced nausea and vomiting, aprepitant is given with a corticosteroid and a 5-hydroxytryptamine type 3 antagonist, such as dolasetron. Dolasetron is converted to the active metabolite hydrodolasetron, which is cleared largely via CYP2D6. The authors determined whether aprepitant, a moderate CYP3A4 inhibitor, alters hydrodolasetron pharmacokinetics in CYP2D6 poor and extensive metabolizers. Six CYP2D6 poor and 6 extensive metabolizers were randomized in an open-label, crossover fashion to treatment A (dolasetron 100 mg on day 1) and treatment B (dolasetron 100 mg plus aprepitant 125 mg on day 1, aprepitant 80 mg on days 2-3). For hydrodolasetron area under the concentration-versus-time curve (AUC0-infinity) and peak plasma concentration (Cmax), geometric mean ratios (B/A) and 90% confidence intervals (CIs) fell below the predefined limit (2.0) for clinical significance (AUC0-infinity, 1.09 [90% CI, 1.01-1.18], Cmax, 1.08 [90% CI, 0.94-1.24]). Aprepitant did not affect the pharmacokinetics of hydrodolasetron, regardless of CYP2D6 metabolizer type, and was generally well tolerated when coadministered with dolasetron in volunteers.

Reappraisal of the role of dolasetron in prevention and treatment of nausea and vomiting associated with surgery or chemotherapy

Chemotherapy-induced nausea and vomiting and postoperative nausea and vomiting are one of the most frequent but also very concerning consequences for patients undergoing chemotherapy or surgical procedures under general anesthesia. There are a variety of mechanisms involved in the activation of nausea and vomiting. Serotonin, a ubiquitous central and peripheral neurotransmitter, is thought to be the predominant mediator of the perception of nausea and triggering of the vomiting response in both the brain and the periphery via the 5-hydroxytryptamine type 3 (5-HT₃) receptor pathways. 5-HT₃ receptor antagonists disrupt this pathway, largely at the level of the vagal afferent pathways, to decrease nausea and vomiting. This review will focus on dolasetron, an older but sill commonly used 5-HT₃ receptor antagonist and its multimodal mechanism of action, safety and tolerability, patient considerations, and a review of the current literature on its use to combat both chemotherapy-induced and postoperative nausea and vomiting in these two important patient populations.

Acute effect of palonosetron on electrocardiographic parameters in cancer patients: a prospective study

OBJECTIVES

Palonosetron is a novel 5-hydroxytryptamine(3) (5 HT(3)) receptor antagonist, which has been shown to be superior to first generation 5 HT(3) receptor antagonists regarding the prevention of acute, delayed and overall chemotherapy-induced nausea and vomiting. First generation 5 HT(3) receptor antagonists may induce electrocardiographic changes of heart rate and repolarization. The acute cardiac effect of palonosteron is unknown. The purpose of this study is to determine acute effects of palonosetron on electrocardiographic (ECG) parameters in cancer patients.

MATERIALS AND METHODS

The study had a prospective design. Seventy-six cancer patients with normal cardiac function who received palonosetron for prevention of chemotherapy-induced nausea and vomiting were enrolled. Standard 12-lead ECG recordings were performed at baseline and 30 min after palonosetron administration. P wave durations and corrected QT intervals were measured; P wave dispersion (Pd) and QTc dispersion were calculated.

RESULTS

Median heart rate did not differ among 76 patients enrolled before and after palonosetron administration (p: 0.6). Systolic and diastolic blood pressures were not significantly different before and after palonosteron (p values 0.9 and 0.3, respectively). Although median QT min value was higher after palonosetron administration than before palonosetron administration, the difference was not statistically significant (p: 0.6).

CONCLUSION

Palonosetron seems to have no acute arrhythmogenic potential.

Electrocardiographic findings of palonosetron in cancer patients

PURPOSE

Nausea and vomiting are among the major problems occurring during and after the chemotherapy treatments of cancer patients. The recently developed 5-HT(3) antagonists have proved much more effective than former agents. Several studies have shown that these agents cause certain ECG changes. We aimed to evaluate the ECG changes caused by palonosetron, one of the new 5-HT(3) antagonists.

METHODS

Our study includes a total of 50 patients diagnosed with solid-organ tumors receiving chemotherapy. The patients were applied 12-lead ECG before palonosetron infusion. Afterwards, subsequent ECGs were applied on the 30th, 60th, and 90th minutes following the infusion of palonosetron. Arterial blood pressure was measured before and after the infusion. PR, QRS, QT, QTmax, QTmin, QTd, Pmax, Pmin, Pd, QTc, QTcmax, QTcmin, and QTcd values were evaluated for each ECG.

RESULTS

We did not detect significant correlations between the systolic and diastolic blood pressures before and after (30 min) palonosetron infusion (p > 0.05). However, there was a statistically significant decrease in heart rate (p = 0.000). The evaluation of ECG findings revealed that there was a significant prolongation in PR distance, as shown by the comparisons of 0 min with 30, 60, and 90 min. On the other hand, there was no significant difference in QRS, QT, QTmax, QTmin, QTd, Pmax, Pmin, Pd, QTc, QTcmax, QTcmin, and QTcd values (p > 0.05).

CONCLUSION

In this study, we revealed that palonosetron did not cause any severe rhythmic disorders or symptomatic ECG changes. We concluded that it could be safe to administer palonosetron antiemetically.

Pharmacologic management of postoperative nausea and vomiting

INTRODUCTION

As advances in the safety and efficacy of surgery and anesthesia have been made, other complications such as postoperative nausea and vomiting (PONV) have become more apparent. PONV occurs after 30% of all surgeries, and incidences as high as 80% have been reported among patients at high risk.

AREAS COVERED

This review provides a brief overview of the etiology and mechanisms of emesis and of known risk factors for PONV. It also covers pharmacologic therapies, appropriate management strategies, prophylactic strategies, multimodal therapy and rescue treatment.

EXPERT OPINION

The main triggers for PONV are general anesthesia with inhalational anesthetics and opioids. When given to susceptible patients, e.g., females, the risk may be as high as 80%. In such patients, opioid-free regional anesthesia would be the most logical approach. However, if general anesthesia is needed, we prefer total intravenous anesthesia as it eliminates the use of inhalational anesthetics and reduces the risk for PONV. Importantly, efficacy of antiemetic interventions is independent as long as interventions have different mechanisms. Thus, for practical purposes, we prefer to titrate the use of antiemetics according to the validated Apfel simplified risk score. If a patient has 0, 1, 2, 3 or 4 of the four risk factors, we apply a similar number of antiemetic strategies.

Value of non-clinical cardiac repolarization assays in supporting the discovery and development of safer medicines

Non-clinical QT-related assays aligned to the pharmaceutical drug discovery and development phases are used in several ways. During the early discovery phases, assays are used for hazard identification and wherever possible for hazard elimination. The data generated enable us to: (i) establish structure-activity relationships and thereby; (ii) influence the medicinal chemistry design and provide tools for effective decision making; and provide structure-activity data for in silico predictive databases; (iii) solve problems earlier; (iv) provide reassurance for compound or project to progress; and (v) refine strategies as scientific and technical knowledge grows. For compounds progressing into pre-clinical development, the 'core battery' QT-related data enable an integrated risk assessment to: (i) fulfil regulatory requirements; (ii) assess the safety and risk-benefit for compound progression to man; (iii) contribute to defining the starting dose during the phase I clinical trials; (iv) influence the design of the phase I clinical trials; (v) identify clinically relevant safety biomarkers; and (vi) contribute to the patient risk management plan. Once a compound progresses into clinical development, QT-related data can be applied in the context of risk management and risk mitigation. The data from 'follow-up' studies can be used to: (i) support regulatory approval; (ii) investigate discrepancies that may have emerged within and/or between non-clinical and clinical data; (iii) understand the mechanism of an undesirable pharmacodynamic effect; (iv) provide reassurance for progression into multiple dosing in humans and/or large-scale clinical trials; and (v) assess drug-drug interactions. Based on emerging data, the integrated risk assessment is then reviewed in this article, and the benefit-risk for compound progression was re-assessed. Project examples are provided to illustrate the impact of non-clinical data to support compound progression throughout the drug discovery and development phases, and regulatory approval.

Coronary Vasospasm and Atrial Fibrillation Associated with Ondansetron Therapy

Objective:

To provide further evidence of cardiovascular adverse effects of ondansetron, including new-onset atrial fibrillation, ST segment elevation, and chest pain subsequent to ondansetron administration, and to review cardiovascular adverse events related to several 5-hydroxytryptamine type 3 (5-HT3) receptor antagonists.

Case Summary:

A 51-year-old male with an uncomplicated past medical history was admitted for an elective inguinal hernia repair and septoplasty. His maintenance medications were discontinued prior to surgery. After a second 4-mg dose of intravenous ondansetron was administered, he developed nausea and diaphoresis. His electrocardiograph revealed new-onset atrial fibrillation and inferolateral ST segment elevation with ST segment alternans. During emergent cardiac catheterization, no obstructive coronary artery disease was evident. The patient's heart rhythm was electrically converted to normal sinus rhythm. During 3 years of follow-up, he has had no return of chest pain or hypotension.

Discussion:

Although considered a safe class of medications by many clinicians, several of the 5-HT3 receptor antagonists have been associated with serious cardiovascular effects. Three case reports described cardiac dysrhythmias and 9 documented coronary vasospasm and chest pain, possibly resulting from ondansetron. This is the first reported case of a combination of hypotension, atrial fibrillation, ST segment elevation, and chest pain following ondansetron administration after elective surgery in a healthy adult male with a nonconfounding medication profile. The Naranjo probability scale indicated that ondansetron was the probable cause of these cardiovascular events.

Conclusions:

This case report supports the concern regarding cardiovascular adverse effects of ondansetron. Clinicians should be aware of cardiovascular adverse reactions that may be associated with intravenous ondansetron and monitor for electrocardiographic changes as indicated. Further investigation is needed to delineate the actual incidence of cardiovascular effects associated with ondansetron and whether the intravenous rate of administration is a contributing factor.

Antiemetic care for patients with breast cancer: focus on drug interactions and safety concerns

PURPOSE

The drug interactions and adverse events that should be considered when individualizing antiemetic therapy for patients undergoing treatment for breast cancer are reviewed.

SUMMARY

A variety of antiemetic agents are available, including antihistamines, dopamine-receptor antagonists, serotonin-receptor antagonists, and neurokinin-receptor antagonists. To ensure optimal symptom control for each patient without unnecessarily prolonging treatment, patient- and treatment-specific risk factors must be considered. Neurokinin-receptor antagonists, the newest class of antiemetics, are effective in preventing acute and delayed chemotherapy-induced nausea and vomiting but must be used in combination with a serotonin-receptor antagonist and a corticosteroid. The serotonin-receptor antagonists have become the mainstay of antiemetic therapy, but current guidelines do not distinguish among the different agents in this class. However, there are distinct pharmacologic differences that may affect the potential for drug interactions and, ultimately, patient outcomes and the occurrence of adverse events. Therefore, the potential for drug interactions must be considered when selecting an antiemetic, particularly for patients who are taking multiple concomitant medications. Further, because a number of breast cancer therapies and some antiemetic agents carry cardiovascular warnings or precautions and since breast cancer patients may already be suffering from cardiovascular complications, the possible cardiotoxic effects of the antiemetic or chemotherapy agents or the combinations of these agents should be considered.

CONCLUSION

Antiemetic treatment is essential for patients with breast cancer who are undergoing moderately to highly emetogenic cytotoxic treatment. When selecting an antiemetic, clinicians must select an agent that provides optimal protection against nausea and vomiting while avoiding drug-drug interactions and additional adverse events.

Haloperidol is as effective as ondansetron for preventing postoperative nausea and vomiting

PURPOSE

Recent warnings regarding the safety of droperidol have limited use of this drug as an antiemetic. Haloperidol, a butyrophenone derivative similar to droperidol, has not been rigorously evaluated as an antiemetic. The aim of this study was to compare the prophylactic antiemetic efficacy of haloperidol vs ondansetron for the prevention of postoperative nausea and vomiting (PONV) after general anesthesia.

METHODS

Ninety non-smoking female patients were eligible to participate in this randomized double-blinded study. Approximately 30 min before the end of surgery, patients were randomly assigned to receive either haloperidol 2 mg iv, or ondansetron 4 mg iv, respectively. The incidence of PONV, average pain and sedation scores, recovery times, and changes of the rate-corrected QT (QTc) interval were observed postoperatively.

RESULTS

The proportion of patients who experienced PONV in the first 24 hr was similar in the two groups (28% and 26% for haloperidol and ondansetron groups, respectively). The incidence of PONV was significantly less in both groups than predicted according to the patients' underlying risks (53% for the haloperidol group, P=0.016; 51% for the ondansetron group, P=0.015). Pain scores, sedation scores, and recovery times were similar in the two groups, and no prolongation of the QTc interval was observed in either group.

CONCLUSIONS

Haloperidol 2 mg iv given 30 min before the end of surgery is effective in preventing PONV, with efficacy comparable to ondansetron 4 mg iv for the first 24 hr after general anesthesia.

Prophylaxis of postoperative nausea and vomiting: controversies in the use of serotonin 5-hydroxytryptamine subtype 3 receptor antagonists

Postoperative nausea and vomiting (PONV) continues to be a "big little problem" despite recent advances in anesthesia. Because of an increased interest in, and the abundant publications on this topic, guidelines for the management of PONV were published in 2003. Several key but controversial issues regarding PONV prophylaxis were left unaddressed, however. These included whether clinical differences exist between the 5-hydroxytryptamine subtype 3 (5-HT3) receptor antagonists, concern over optimal dosage and timing of administration, optimal 5-HT3 receptor antagonist combination therapy, and whether rescue therapy is effective after prior administration of the same or a different 5-HT3 receptor antagonist. The application of these antiemetics in clinical practice has raised questions regarding the role of the 5-HT3 receptor antagonists in the treatment of postdischarge nausea and vomiting and opioid-induced nausea and vomiting. A brief overview of the incidence, risk factors and current management recommendations for PONV and current controversies with special emphasis on the 5-HT3 receptor antagonists, is discussed.

Electrocardiographic findings after 5-HT3 receptor antagonists and chemotherapy in children with cancer

BACKGROUND

The antiemetic efficacy of serotonin-type 3 (5-HT3) receptor antagonists has been found to be superior to older antiemetic drugs in cancer patients. Following the administration of these agents, changes in ECG parameters and increased or decreased heart rates have been demonstrated, but there is no sufficient data in children with cancer who are treated with cytotoxic agents. The objective of this study is to evaluate the ECG changes after administration of 5-HT3 receptor antagonists and chemotherapeutic agents in children with cancer.

PROCEDURE

Thirty-eight patients with an age range between 2 and 19 years receiving chemotherapy for solid tumors were included in the study. The patients received 5-HT3 receptor antagonists 30 min before antineoplastic agents in 83 chemotherapy days. Antiemetic therapy consisted of ondansetron in 43 and granisetron in 40 chemotherapy days. Twelve-leads ECGs were obtained four times at the first day of each chemotherapy: just before 30, 90 min, and 24 hr after 5-HT3 receptor antagonists were given. Rate, rhythm, PR interval, QRS duration, ST segment, the shortest (QTca) and the longest (QTcb) QTc intervals with QTc dispersion (QTcd) were all evaluated.

RESULTS

We found a significant shortening of the PR interval and QRS complex durations in the granisetron group at 90th min and at 24th hr, respectively. Also, granisetron infusion caused a significant prolongation of the QTca interval at 90 min.

CONCLUSION

Although we observed minor ECG changes after 5-HT3 receptor antagonists and chemotherapy, neither dangerous rhythm disturbances nor serious ECG changes were seen.