Long-acting serotonin antagonist (Palonosetron) and the NK-1 receptor antagonists: does extended duration of action improve efficacy?

Palonosetron as prophylaxis for post-discharge nausea and vomiting: a prospective, randomised, double-blind, placebo-controlled trial in ambulatory surgery

BACKGROUND

Approximately 25% of ambulatory surgery patients experience post-discharge nausea and vomiting (PDNV). We aimed to investigate whether palonosetron, a long-acting anti-emetic, decreases the incidence of PDNV in high-risk patients.

METHODS

In this prospective, randomised, double-blind, placebo-controlled trial, 170 male and female patients undergoing ambulatory surgery under general anaesthesia, with a high predicted risk for PDNV, were randomised to receive either palonosetron 75 μg i.v. (n=84) or normal saline (n=86) before discharge. During the first 3 postoperative days (PODs), we measured outcomes using a patient questionnaire. The primary outcome was the incidence of a complete response (no nausea, vomiting, or use of rescue medication) until POD 2. Secondary outcomes included the incidence of PDNV each day until POD 3.

RESULTS

The incidence of a complete response until POD 2 was 48% (n=32) in the palonosetron group and 36% (n=25) in the placebo group (odds ratio 1.69 [95% confidence interval: 0.85-3.37]; P=0.131). No significant difference in the incidence of PDNV was observed between the two groups on the day of surgery (47% vs 56%; P=0.31). Significant differences in the incidence of PDNV were found on POD 1 (18% vs 34%; P=0.033) and POD 2 (9% vs 27%; P=0.007). No differences were observed on POD 3 (15% vs 13%; P=0.700).

CONCLUSIONS

Compared with placebo, palonosetron did not reduce the overall incidence of PDNV up to POD 2. The lower incidence of PDNV on POD 1 and POD 2 in the palonosetron group requires further investigation.

CLINICAL TRIAL REGISTRATION

EudraCT 2015-003956-32.

Pharmacokinetics, Safety, and Tolerability of Rolapitant Administered Intravenously Following Single Ascending and Multiple Ascending Doses in Healthy Subjects

Rolapitant is a selective and long-acting neurokinin-1 receptor antagonist approved in an oral formulation in combination with dexamethasone and a 5-hydroxytryptamine type 3 receptor antagonist for the prevention of delayed chemotherapy-induced nausea and vomiting in adults. The pharmacokinetic and safety profiles of intravenous (IV) rolapitant were evaluated in two open-label, phase 1 trials in healthy subjects. Single ascending dose (SAD) and multiple ascending dose studies were conducted in one trial (PR-11-5012-C), and a supratherapeutic SAD study was conducted in a separate trial (PR-11-5022-C). In the SAD and supratherapeutic studies, rolapitant maximum plasma concentration, area under the plasma drug concentration-time curve (AUC) from time zero to time of last measured concentration, and AUC from time zero to infinity increased dose-proportionally following single IV infusions of 18 to 270 mg. In the multiple ascending dose study, following 10 daily IV infusions of rolapitant 18, 36, or 54 mg, the mean day 10:day 1 maximum concentration ratio was 1.97, 1.52, and 2.07, respectively, and the mean day 10:day 1 ratio of AUC from 0 to 24 hours was 4.30, 4.59, and 5.38, respectively, indicating drug accumulation over time. Across all studies, rolapitant was gradually eliminated from plasma, with a half-life of 135-231 hours. Rolapitant was safe and well tolerated across all studies, with no serious or severe rolapitant-related treatment-emergent adverse events. The most common rolapitant-related treatment-emergent adverse events were headache, dry mouth, and dizziness, which were predominantly mild in severity. Overall, the pharmacokinetic and safety profiles of IV rolapitant were consistent with those of the oral formulation.

Neurokinin-1 receptor antagonists in preventing postoperative nausea and vomiting: a systematic review and meta-analysis

Newly developed neurokinin-1 receptor (NK-1R) antagonists have been recently tried in the prevention of postoperative nausea and vomiting (PONV). This systematic review and meta-analysis was conducted to explore whether NK-1R antagonists were effective in preventing PONV.The PRISMA statement guidelines were followed. Randomized clinical trials (RCTs) that tested the preventive effects of NK-1R antagonists on PONV were identified by searching EMBASE, CINAHL, PubMed, and the Cochrane Library databases followed by screening. Data extraction was performed using a predefined form and trial quality was assessed using a modified Jadad scale. The primary outcome measure was the incidence of PONV. Meta-analysis was performed for studies using similar interventions. Network meta-analysis (NMA) was conducted to compare the anti-vomiting effects of placebo, ondansetron, and aprepitant at different doses.Fourteen RCTs were included. Meta-analysis found that 80 mg of aprepitant could reduce the incidences of nausea (3 RCTs with 224 patients, pooled risk ratio (RR) = 0.60, 95% confidence interval (CI) = 0.47 to 0.75), and vomiting (3 RCTs with 224 patients, pooled RR = 0.13, 95% CI = 0.04 to 0.37) compared with placebo. Neither 40 mg (3 RCTs with 1171 patients, RR = 0.47, 95% CI = 0.37 to 0.60) nor 125 mg (2 RCTs with 1058 patients, RR = 0.32, 95% CI = 0.13 to 0.78) of aprepitant showed superiority over 4 mg of ondansetron in preventing postoperative vomiting. NMA did not find a dose-dependent effect of aprepitant on preventing postoperative vomiting.Limited data suggested that NK-1R antagonists, especially aprepitant were effective in preventing PONV compared with placebo. More large-sampled high-quality RCTs are needed.