Lack of effect of aprepitant on the pharmacokinetics of docetaxel in cancer patients

Background Aprepitant is a selective neurokinin-1 receptor antagonist that is effective for the prevention of nausea and vomiting caused by highly emetogenic chemotherapy. In vitro, aprepitant is a moderate inhibitor of the CYP3A4 enzyme, which is involved in the clearance of several chemotherapeutic agents. In this study we examined the potential for aprepitant to affect the pharmacokinetics and toxicity of intravenously administered docetaxel, a chemotherapeutic agent that is primarily metabolized by CYP3A4.Methods A total of 11 cancer patients (4 male, 7 female, aged 50–68 years) were enrolled in this multicenter, randomized, open-label, two-period, crossover study. Patients received a single infusion of docetaxel monotherapy, 60–100 mg/m², on two occasions at least 3 weeks apart. During one of the cycles (treatment A), patients received docetaxel alone. During the alternate cycle (treatment B), they also received aprepitant 125 mg orally 1 h prior to docetaxel infusion (day 1), and a single oral dose of aprepitant 80 mg on days 2 and 3. The pharmacokinetic profile of docetaxel was assessed over 30 h following docetaxel infusion. Blood counts were monitored on days 1, 4, 7, and 14.Results Ten patients completed the study. Concomitant administration of aprepitant did not cause any statistically or clinically significant changes in docetaxel pharmacokinetics. Values for docetaxel alone (treatment A) versus docetaxel with aprepitant (treatment B) were as follows: geometric mean AUC_0–last was 3.26 vs 3.17 g h/ml (P>0.25; ratio B/A 0.97); geometric mean AUC_0– 3.51 vs 3.39 g h/ml (P>0.25; ratio B/A 0.96); geometric mean C_max was 3.53 vs 3.37 g/ml (P>0.25; ratio B/A 0.95); and geometric mean plasma clearance was 23.3 vs 24.2 l/h/m² (P>0.25; ratio B/A 1.04). The corresponding harmonic mean half-life values were 10.1 and 8.5 h. The two treatment regimens had similar tolerability profiles; the median absolute neutrophil count nadirs were 681/mm³ during treatment with docetaxel alone and 975/mm³ during aprepitant coadministration.Conclusions Aprepitant had no clinically significant effect on either the pharmacokinetics or toxicity of standard doses of docetaxel in cancer patients. Aprepitant at clinically recommended doses may have a low potential to affect the pharmacokinetics of intravenous chemotherapeutic agents metabolized by CYP3A4.     

Population pharmacokinetics of aprepitant and dexamethasone in the prevention of chemotherapy-induced nausea and vomiting

Purpose  To develop a population pharmacokinetic model of aprepitant and dexamethasone in Japanese patients with cancer, explore the factors that affect the pharmacokinetics of aprepitant, and evaluate the effect of aprepitant on the clearance of intravenous dexamethasone. Methods  A total of 897 aprepitant concentration measurements were obtained from 290 cancer patients and 25 healthy volunteers. For dexamethasone, a total of 847 measurements were obtained from 440 patients who were co-administered aprepitant (40, 125 mg, or placebo). Plasma concentration of aprepitant and dexamethasone were determined by liquid chromatography connected with a tandem mass spectrometer and analyzed by a population approach using NONMEM software. Results  The plasma concentration time course of aprepitant was described using a one-compartment model with first-order absorption and lag time. Oral clearance (CL/F) of aprepitant was changed by aprepitant dose at doses of 40 or 125 mg. Body weight was the most influential intrinsic factor to CL/F of aprepitant. Age, ALT, and BUN also had mild effects on the CL/F. Typical population estimates of CL/F, apparent distribution volume (V _d/F), absorption constant (K _a) and absorption lag time were 1.54 L/h, 72.1 L, 0.893/h and 0.295 h, respectively. Inter-individual variability in CL/F, V _d/F and K _a were 53.9, 21.0, and 141%, respectively; intra-individual variability was 27.7%. The plasma concentration time course of intravenous dexamethasone was also described using a one-compartment model. Clearance of dexamethasone was decreased 24.7 and 47.5% by co-administration of aprepitant 40 and 125 mg. All final model estimates of aprepitant and dexamethasone fell within 10% of the bootstrapped mean. Conclusions  A pharmacokinetic model for aprepitant has been developed that incorporates body weight, age, ALT, BUN and aprepitant dose to predict the CL/F. The results of population pharmacokinetic analysis of dexamethasone support dose adjustment of dexamethasone in the case of co-administration with aprepitant.     

Aprepitant exerts anti-fibrotic effect via inhibition of TGF-β/Smad3 pathway in bleomycin-induced pulmonary fibrosis in rats

Bleomycin is a well-recognized antineoplastic drug. However, pulmonary fibrosis (PF) is considered to be the principal drawback that greatly limits its use. Here, we sought to investigate ability of the neurokinin receptor 1 blocker, aprepitant, to prevent PF caused by bleomycin. Male adult Wistar rat groups were given a single intratracheal injection of bleomycin, either alone or in combination with aprepitant therapy for 3 or 14 days. Collagen deposition and a rise in transforming growth factor beta (TGF-β) immunoreactivity in lung tissue serve as evidence of bleomycin-induced PF. The serum levels of lactate dehydrogenase, alkaline phosphatase, and total antioxidant improved after aprepitant therapy.Additionally, it reduced the protein expressions of interferon alpha, tumor necrosis factor alpha, and lung lipid peroxidation. Moreover, aprepitant treatment led to an increase in the antioxidant indices glutathione, glutathione peroxidase, and catalase. Aprepitant is postulated to protect against bleomycin-induced PF by decreasing TGF-β, phosphorylating Smad3, and increasing interleukin 37, an anti-fibrotic cytokine, and G Protein-coupled Receptor Kinase 2. Aprepitant for 14 days considerably exceeded aprepitant for 3 days in terms of improving lung damage and having an anti-fibrotic impact. In conclusion, aprepitant treatment for 14 days may be used as an adjuvant to bleomycin therapy to prevent PF, mostly through inhibiting the TGF-/p-Smad3 fibrotic pathway.     

Efficacy of aprepitant for CHOP chemotherapy-induced nausea,vomiting, and anorexia

The objective of this study was to evaluate whether aprepitant in addition to 5-HT3 receptor antagonist is useful for preventing chemotherapy-induced nausea and vomiting (CINV) and anorexia in patients receiving CHOP therapy, and to evaluate the relationship between in vivo kinetics of plasma substance P and these adverse events. Patients with malignant lymphoma who received CHOP chemotherapy or THP (THP-ADR)-COP therapy were investigated for CINV and anorexia for 5 days after the start of chemotherapy. With the first course of chemotherapy, all patients received only granisetron on day1 as an antiemetic. Patients who experienced nausea, vomiting, or anorexia exceeding grade 1 in the first course received aprepitant for 3 days in addition to granisetron with the second course of CHOP chemotherapy. Plasma substance P concentrations at 24 and 72 hours after chemotherapy were measured. Nineteen patients were evaluated. Nausea, vomiting, or anorexia was observed with the first course in 7 of 19 patients. During the second course with aprepitant, no patients experienced vomiting, and the toxicity grade of nausea, vomiting, or anorexia was decreased compared with those in the first course. Substance P concentrations showed no differences after chemotherapy, in patients with nausea, vomiting, or anorexia and in patients without. The addition of aprepitant to 5-HT3 receptor antagonist appears effective for CINV or anorexia for patients who received CHOP chemotherapy.     

Incidence of chemotherapy-induced nausea and vomiting associated with docetaxel and cyclophosphamide in early breast cancer patients and aprepitant efficacy as salvage therapy. Results from the Spanish Breast Cancer Group/2009-02 study

BackgroundDocetaxel–cyclophosphamide (TC) has become a common regimen in moderate-high-risk early breast cancer (EBC), but the incidence of chemotherapy-induced nausea and vomiting (CINV) with this regimen is not well established. This trial investigates the effect of guideline-consistent prophylaxis on CINV related to TC regimen and explores the efficacy of aprepitant among resistant patients.Patients and MethodsThis prospective multicentre study enrolled 212 chemotherapy-naïve EBC patients receiving T-75 mg/m² and C-600 mg/m². Antiemetic therapy on the first cycle consisted of dexamethasone for 3 d plus 5-hydroxytryptamine (5-HT₃) antagonists on day 1, according to Multinational Association of Supportive Care in Cancer guidelines. The primary end-point was complete response (CR) (no emesis and no need of rescue treatment within the initial 120 h). Patients failing CR on cycle 1 entered in a single-arm study exploring the efficacy of aprepitant on the second cycle. Patients' diaries and Functional Living Index-Emesis (FLIE) questionnaires were collected in cycles 1 and 2.ResultsAmong the 185 evaluable patients on cycle 1, 161 (87%, 95% confidence interval [CI]: 82.2–91.8) achieved a CR. Twenty-three patients received aprepitant on cycle 2, and 12 reached a CR (52.2%, 95% CI: 31.8–72.6). The absence of CR had a very substantial impact on quality of life on cycles 1 (FLIE before and after: 23.8–38.1, p = 0.0124) and 2 (18.3–42.9, p = 0.0059).ConclusionsGuideline-consistent antiemetic prophylaxis for the TC regimen is associated with a low incidence of CINV. Aprepitant is effective as secondary prevention of CINV and should be considered as rescue therapy in patients treated with moderate emetogenic chemotherapy.     

Aprepitant when added to a standard antiemetic regimen consisting of ondansetron and dexamethasone does not affect vinorelbine pharmacokinetics in cancer patients

Purpose Aprepitant, a selective neurokinin-1 (NK-1) receptor antagonist approved for the treatment and prevention of emesis caused by moderately and highly emetogenic chemotherapy, is an inhibitor, inducer, and substrate of the cytochrome P450 3194 pathway. The CYP3A4 pathway is the major pathway of the metabolism of vinorelbine, a vinca alkaloid frequently used in combination with cisplatin. Therefore, we studied the potential interaction of the aprepitant 3-day antiemetic regimen on the pharmacokinetics of vinorelbine. Patients and methods Fourteen patients with metastatic solid tumors were included in this open-label, balanced, 2-period crossover study. In treatment arm A, vinorelbine (25 mg/m² weekly) was administered alone, while in treatment arm B the same dose of vinorelbine was administered following the administration of the aprepitant antiemetic regimen on day 1 and alone on day 8. The antiemetic regimen of aprepitant was comprised of the following; on day 1: 125 mg aprepitant, 12 mg dexamethasone, and 32 mg ondansetron; on days 2 and 3: 80 mg aprepitant and 8 mg dexamethasone and on day 4: 8 mg dexamethasone. Blood samples for vinorelbine pharmacokinetic analysis were collected over 96 h. Results Two patients discontinued the study due to adverse events that were judged not to be drug-related. Complete pharmacokinetic data of vinorelbine administered alone and with the aprepitant antiemetic regimen were obtained in 12 patients. The mean plasma concentration profile of vinorelbine administered with aprepitant was identical to that following vinorelbine administered alone, with geometric mean vinorelbine plasma AUC ratios of treatment B day 1/treatment A day 1 and of treatment B day 8/treatment A day of 1.01 (0.93, 1.10) and 1.00 (0.92, 1.08), respectively. Conclusion As the aprepitant antiemetic regimen has no detectable inhibitory or inductive effect on the pharmacokinetics of vinorelbine, aprepitant when added to a standard antiemetic regimen consisting of ondansetron and dexamethasone can be safely combined with vinorelbine at clinically recommended doses.     

阿瑞匹坦用于肺腺癌紫杉醇联合顺铂化疗引起恶心呕吐的临床研究

目的观察阿瑞匹坦在肺腺癌紫杉醇联合顺铂方案化疗中的急性期及延迟期止吐疗效和安全性。方法 50例肺腺癌患者,均接受紫杉醇联合顺铂的TP方案化疗,随机分为实验组及对照组,每组25例。对照组患者接受5-HT3受体拮抗剂托烷司琼、地塞米松预防止吐,实验组在对照组基础上联合应用阿瑞匹坦预防止吐。完成1个周期化疗后,评估两组患者在化疗后急性期及延迟期恶心呕吐情况及不良反应。结果 50例患者均按期完成1个周期的TP方案化疗,实验组和对照组急性恶心、呕吐完全缓解率(CR)分别为44%和32%(χ~2=0.764,P>0.05),有效率(RR)分别为80%和72%(χ~2=0.439,P>0.05),差异无统计学意义。实验组和对照组延迟性恶心呕吐CR分别为52%和24%(χ~2=4.160,P<0.05),RR分别为76%和44%(χ~2=5.333,P<0.05),差异有统计学意义。两组患者不良反应主要包括头晕、乏力、呃逆、腹胀、便秘,均为轻度,差异无统计学意义。结论阿瑞匹坦联合托烷司琼、地塞米松方案预防肺腺癌紫杉醇联合顺铂化疗引起的急性期及延迟期恶心呕吐疗效确切,安全性高,值得临床进一步应用推广。     

A randomized study of olanzapine-containing versus standard antiemetic regimens for the prevention of chemotherapy-induced nausea and vomiting in Chinese breast cancer patients

ObjectivesChemotherapy-induced nausea and vomiting (CINV) are distressing symptoms. This randomized study evaluated the antiemetic efficacies of standard antiemetic regimen with/without olanzapine.Patients and methodsEligible patients were chemotherapy-naive Chinese breast cancer patients who were planned for (neo)adjuvant doxorubicin/cyclophosphamide. Antiemetic regimen for all studied population included aprepitant, ondansetron and dexamethasone; patients were randomized to Olanzapine (with olanzapine) or Standard arms (without olanzapine). Patients filled in self-reported diaries and completed visual analogue scales for nausea, as well as Functional Living Index-Emesis questionnaires. Blood profiles including fasting glucose and lipids were monitored.Results120 patients were randomized. In Cycle 1 doxorubicin/cyclophosphamide, the Olanzapine arm had significantly higher rates of “Complete Response” than the Standard arm: 65.0% vs 38.3% in the overall period (p = 0.0035), 70.0% vs 51.7% in the acute period (p = 0.0397) and 92.9% vs 74.2% in the delayed period (p = 0.0254). Olanzapine arm also had significantly higher rates of “No significant nausea” and “No nausea” during all 3 time-frames and better QOL. Similar findings were also revealed throughout multiple cycles. Pre-study abnormalities in glucose and lipids occurred in 39.7% and 34.2% of the studied population respectively; there were no differences in these parameters between the two arms at end-of-study assessment.ConclusionThe addition of olanzapine to standard aprepitant-based antiemetic regimen provides clinically meaningful improvement in controlling CINV. This was associated with a positive impact on QOL and tolerable toxicity profiles among Chinese breast cancer patients receiving doxorubicin/cyclophosphamide chemotherapy. Further studies on metabolic profiles of breast cancer patients are warranted.     

Cost-effectiveness analysis of aprepitant in the prevention of chemotherapy-induced nausea and vomiting in Belgium

OBJECTIVES: Chemotherapy-induced nausea and vomiting (CINV) remains a major adverse effect of cancer chemotherapy which may increase morbidity, reduce quality of life and threaten the success of cancer therapy. Aprepitant is effective in preventing CINV, achieving higher complete response (no emesis and no rescue therapy) compared to standard prevention, in patients receiving either highly (HEC) or moderately emetogenic chemotherapy (MEC; absolute reduction = 11 and 13%, respectively). We assessed the cost effectiveness of aprepitant-based vs standard prevention in these indications in Belgium. MATERIALS AND METHODS: A decision analytical model was developed in MS Excel (Fig. 1). To estimate resource use, two approaches were used. The first is based on the preventive regimens applied in randomized controlled trials comparing aprepitant-based CINV prevention (for HEC: aprepitant days 1-3, ondansetron 32 mg i.v. day 1, oral placebo twice daily days 2-4, oral dexamethasone days 1-4; for MEC: aprepitant days 1-3, ondansetron 16 mg p.o. day 1, placebo on days 2-3, oral dexamethasone day 1), vs a standard regimen (for HEC: oral placebo days 1-3, ondansetron 32 mg i.v. day 1 and 16 mg p.o. days 2-4, oral dexamethasone days 1-4; for MEC: oral placebo, ondansetron 16 mg p.o. days 1-3, dexamethasone day 1) The second analysis is based on current real-world resource use in the Belgian setting in the prevention of CINV using a longitudinal Hospital Database. CINV-specific utility values were used to calculate quality-adjusted life years (QALYs). Drug costs were obtained from official reimbursement listings. Treatment costs for CINV were obtained from a German study and adapted to Belgium. RESULTS: The aprepitant-based regimen is associated with 0.003 and 0.014 more QALYs in HEC and MEC, respectively and with per patient savings of 66.84 (trial based) and 74.62 (real-life based) for HEC and 17.95 (trial based) and 21.70 (real-life based) for MEC. Hence, aprepitant is both more effective and less expensive (=dominant). One-way sensitivity analyses were performed on treatment cost of emesis, the clinical benefit of aprepitant and the cost of ondansetron and showed that the results were robust on the first two parameters but sensitive on the decrease in cost of ondansetron for the moderately emetogenic chemotherapy regimens. CONCLUSIONS: In both approaches, the aprepitant-based strategy is more effective and less expensive compared to standard care.