Evaluation of the bioequivalence of tablet and capsule formulations of granisetron in patients undergoing cytotoxic chemotherapy for malignant disease

Pharmacokinetics and repolarization effects of intravenous and transdermal granisetron

PURPOSE

The need for greater clarity about the effects of 5-HT(3) receptor antagonists on cardiac repolarization is apparent in the changing product labeling across this therapeutic class. This study assessed the repolarization effects of granisetron, a 5-HT(3) receptor antagonist antiemetic, administered intravenously and by a granisetron transdermal system (GTDS).

EXPERIMENTAL DESIGN

In a parallel four-arm study, healthy subjects were randomized to receive intravenous granisetron, GTDS, placebo, or oral moxifloxacin (active control). The primary endpoint was difference in change from baseline in mean Fridericia-corrected QT interval (QTcF) between GTDS and placebo (ddQTcF) on days 3 and 5.

RESULTS

A total of 240 subjects were enrolled, 60 in each group. Adequate sensitivity for detection of QTc change was shown by a 5.75 ms lower bound of the 90% confidence interval (CI) for moxifloxacin versus placebo at 2 hours postdose on day 3. Day 3 ddQTcF values varied between 0.2 and 1.9 ms for GTDS (maximum upper bound of 90% CI, 6.88 ms), between -1.2 and 1.6 ms for i.v. granisetron (maximum upper bound of 90% CI, 5.86 ms), and between -3.4 and 4.7 ms for moxifloxacin (maximum upper bound of 90% CI, 13.45 ms). Day 5 findings were similar. Pharmacokinetic-ddQTcF modeling showed a minimally positive slope of 0.157 ms/(ng/mL), but a very low correlation (r = 0.090).

CONCLUSION

GTDS was not associated with statistically or clinically significant effects on QTcF or other electrocardiographic variables. This study provides useful clarification on the effect of granisetron delivered by GTDS on cardiac repolarization.

Randomized crossover pharmacokinetic evaluation of subcutaneous versus intravenous granisetron in cancer patients treated with platinum-based chemotherapy

BACKGROUND

5-HT3-receptor antagonists are one of the mainstays of antiemetic treatment, and they are administered either i.v. or orally. Nevertheless, sometimes neither administration route is feasible, such as in patients unable to admit oral intake managed in an outpatient setting. Our objective was to evaluate the bioavailability of s.c. granisetron.

PATIENTS AND METHODS

Patients receiving platinum-based chemotherapy were randomized to receive 3 mg of granisetron either s.c. or i.v. in a crossover manner during two cycles. Blood and urine samples were collected after each cycle. Pharmacokinetic parameters observed with each administration route were compared by analysis of variance.

RESULTS

From May to November 2005, 31 patients were included and 25 were evaluable. Subcutaneous granisetron resulted in a 27% higher area under the concentration-time curve for 0-12 hours (AUC(0-12h)) and higher levels at 12 hours, with similar values for AUC(0-24h). The maximum concentration was lower with the s.c. than with the i.v. route and was observed 30 minutes following s.c. administration.

CONCLUSION

Granisetron administered s.c. achieves complete bioavailability. This is the first study that shows that s.c. granisetron might be a valid alternative to i.v. delivery. Further trials to confirm clinical equivalence are warranted. This new route of administration might be especially relevant for outpatient management of emesis in cancer patients.

Rapid determination of granisetron in human plasma by liquid chromatography coupled to tandem mass spectrometry and its application to bioequivalence study

A simple, sensitive and rapid method for analysis of granisetron in human plasma, utilizing liquid chromatography tandem mass spectrometry (LC-MS/MS), has been developed and validated to satisfy FDA guidelines for bioanalytical methods. The analyte and internal standard (IS) were isolated from 100microl plasma samples by liquid-liquid extraction (LLE). A Varian 1200l tandem mass spectrometer equipped with an electrospray ionization source was operated in selected reaction monitoring (SRM) mode with the precursor-to-product ion transitions m/z 313.4/138 for granisetron and m/z 270/201 for the IS used for quantitation. The assay exhibited a linear dynamic range of 0.02-20ng/ml for granisetron in human plasma. The lower limit of quantification (LLOQ) was 0.02ng/ml with a relative standard deviation of less than 15%. The mean extraction recovery from spiked plasma samples was 97.9%. The intra-day accuracy of the assay was within 10% of nominal and intra-day precision was better than 15% C.V. A run time of 2.0min for each sample made it possible for high-throughput bioanalysis. The method was employed in a bioequivalence study of two formulations of granisetron hydrochloride 1mg rapidly disintegrating tablets/1mg capsules.

Quantification of granisetron in human plasma by liquid chromatography coupled to electrospray tandem mass spectrometry

A simple, sensitive and rapid high-performance liquid chromatography/electrospray ionization tandem mass spectrometry method was developed and validated for the assay of granisetron in human plasma. Following liquid-liquid extraction, the analytes were separated using an isocratic mobile phase on a reversed-phase C18 column and analyzed by MS in the multiple reaction monitoring mode using the respective [M+H]+ ions, m/z 313/138 for granisetron and m/z 409/228 for the IS. The assay exhibited a linear dynamic range of 0.1-20 ng/mL for granisetron in human plasma. The lower limit of quantification was 100 pg/mL with a relative standard deviation of less than 5%. Acceptable precision and accuracy were obtained for concentrations over the standard curve range. A run time of 2.0 min for each sample made it possible to analyze more than 400 human plasma samples per day. The validated method has been successfully used to analyze human plasma samples for application in pharmacokinetic, bioavailability or bioequivalence studies.

Intravenous pharmacokinetics and absolute oral bioavailability of dolasetron in healthy volunteers: part 1

In this first part of a two-part investigation, the intravenous dose proportionality of dolasetron mesylate, a 5-HT3 receptor antagonist, and the absolute bioavailability of oral dolasetron mesylate were investigated. In an open-label, randomized, four-way crossover design, 24 healthy men between the ages of 19 and 45 years received the following doses: 50, 100, or 200 mg dolasetron mesylate administered by 10-min intravenous infusion or 200 mg dolasetron mesylate solution administered orally. Serial blood and urine samples were collected for 48 h after dosing. Following intravenous administration, dolasetron was rapidly eliminated from plasma, with a mean elimination half-life (t1/2) of less than 10 min. Dolasetron was rarely detected in plasma after oral administration of the 200 mg dose. Hydrodolasetron, the active primary metabolite of dolasetron, appeared rapidly in plasma following both oral and intravenous administration of dolasetron mesylate, with a mean time to maximum concentration (t(max)) of less than 1 h. The mean t1/2 of hydrodolasetron ranged from 6.6-8.8 h. The plasma area under the concentration-time curve (AUC0-infinity)) for both dolasetron and hydrodolasetron increased proportionally with dose over the intravenous dose range of 50-200 mg dolasetron mesylate. Approximately 29-33%) and 22% of the dose was excreted in urine as hydrodolasetron following intravenous and oral administration of dolasetron, respectively. For dolasetron as well as hydrodolasetron, mean systemic clearance (C1), volume of distribution (Vd), and t1/2 were similar at each dolasetron dose. The mean 'apparent' bioavailability of dolasetron calculated using plasma concentrations of hydrodolasetron was 76%. The R(+) enantiomer of hydrodolasetron represented the majority of drug in plasma (> 75%) and urine (> 86%). Dolasetron was well tolerated following both oral and intravenous administration.

Pharmacokinetic profile and clinical efficacy of a once-daily ondansetron suppository in cyclophosphamide-induced emesis: a double blind comparative study with ondansetron tablets

We investigated the pharmacokinetic profile and the efficacy of ondansetron (day 1) given as 16 mg suppository once a day, as compared with ondansetron 8 mg tablets twice daily, in patients receiving moderately emetogenic chemotherapy. The study was primarily aimed at investigating the pharmacokinetics and was part of a large multinational, randomised, double-blind, double-dummy efficacy trial. Pharmacokinetic data were obtained in a total of 20 patients, 11 of whom had received a suppository containing ondansetron, and nine patients had received the oral formulation. The median area under the plasma concentration curve (AUC) obtained with the oral formulation was 226 ng ml-1h-1 (range 91-750), and the median maximum plasma level (Cmax) was 50.5 ng ml-1 (range 24.7-199.6) after a dose of 8 mg. For the ondansetron suppository the median AUC was 140 ng ml-1h-1 range (77-405) and the median Cmax was 17.1 ng ml-1 (range 13-48.3) after a dose of 16 mg. The systemic exposure after correction for the dose difference after the suppository was on average 70% lower than after the tablet. The median time to reach the maximum level (Tmax) was 60 min (range 28-120) with the oral formulation and 209 min (range 90-420) with the suppository. For both the tablet and suppository, there was no apparent relationship between either Cmax or AUC, and efficacy. Although the patient numbers were too small for a formal exposure-response relationship to be derived, the slightly poorer pharmacokinetic performance of the suppository did not appear to be associated with a lessening of control of emesis following chemotherapy. The study demonstrates that the pharmacokinetic analysis of a once-daily 16 mg ondansetron suppository results in appropriate plasma concentrations and AUC, and that this rectal formulation is effective in the protection against nausea and vomiting associated with cyclophosphamide chemotherapy. This formulation will provide a useful alternative to the currently available oral formulation.

High-performance liquid chromatographic determination of granisetron in human plasma

This paper describes a high-performance liquid chromatographic method (HPLC) with fluorometric detection for the analysis of granisetron in plasma. The detection is performed at 305 nm for excitation and 365 nm for emission. The method involves sample clean-up by liquid-liquid extraction. N-(1-Naphthyl) ethylenediamine dihydrochloride is used as internal standard. Toluene and phosphate buffer were added to 0.5 ml of plasma added to the internal standard. After extraction, the organic layer was separated and then evaporated to dryness. The residue was reconstituted in eluent mixture. An aliquot was injected onto the HPLC column, Spherisorb CN, equilibrated with an eluent mixture constituted by acetonitrile-phosphate buffer (pH 4.5) (15:85). The proposed technique is reproducible, selective, reliable, and sensitive. Linear detector responses were observed for the calibration curve standards in the range of 0.50 to 100 ng/ml. Extraction recovery from plasma proved to be more than 90%. Precision expressed as C.V. was in the range 2 to 8%. As low as 0.3 ng of granisetron per ml of plasma can be measured with good accuracy. The method has been validated, and stability tests under various conditions have been performed. Its sensitivity is adequate for pharmacokinetic studies.

Granisetron: the second serotonin-receptor antagonist

OBJECTIVE

To review the pharmacology, pharmacokinetics, clinical efficacy, and adverse effects of granisetron, focusing on critical analysis of published clinical trials and comparison with other antiemetic agents, including ondansetron.

DATA SOURCES

MEDLINE (1966-1995) and CANCERLIT (1991-1995) searches of English-language literature using the terms "granisetron" and "granisetron (rn)" were performed.

STUDY SELECTION AND DATA EXTRACTION

All articles were considered for possible inclusion in this review. Abstracts of clinical trials were included only when they were judged to add critical information not otherwise available in the medical literature. For studies published more than once, the most recent publication was cited.

DATA SYNTHESIS

Nausea and vomiting are rated by patients as the most distressing chemotherapy-related adverse effects and may produce potentially life-threatening complications. The discovery of the role of serotonin in nausea and vomiting and the development of selective serotonin3-receptor (5-HT3) antagonists has significantly diminished the incidence and consequences of chemotherapy-related nausea and vomiting. Granisetron is the second 5-HT3-receptor antagonist to be marketed in the US. Granisetron has been compared with other antiemetic agents, including ondansetron, against highly and moderately emetogenic chemotherapy. The results of these trials have shown granisetron to be superior to conventional antiemetics and as effective as ondansetron in the prevention of chemotherapy-induced nausea and vomiting. The optimal dose of granisetron has yet to be determined. Formulary decisions should be based on a cost comparison among the 5-HT3-receptor antagonists at individual institutions.

CONCLUSIONS

Granisetron is a safe, effective antiemetic agent for the management of nausea and vomiting caused by cancer chemotherapy.

Antiemetic treatment with oral granisetron in patients receiving moderately emetogenic chemotherapy: a dose-ranging study

The antiemetic efficacy and tolerability of four different oral doses of granisetron (0.25, 0.5, 1, and 2 mg twice daily [BID]) were compared in a randomized, double-blind, parallel-group, multicenter study involving 930 patients with malignant disease receiving moderately emetogenic chemotherapy over a 7- or 14-day period. On the first day of granisetron treatment, a statistically significant association between complete response and dose was seen (P = 0.001), with the maximum response (81.1%) achieved at a dose of 1 mg BID. The 24-hour complete response rate with granisetron 1 mg BID was significantly higher than with 0.25 mg BID (61.1%) or 0.5 mg BID (70.2%) (P < 0.009). The complete response rate for days 0 to 6 was significantly higher with granisetron at 1 mg BID (58.8%) than with 0.25 mg BID (43.7%) or 0.5 mg BID (53.6%) (P < 0.009). No advantage in terms of complete response rate was shown for 2 mg BID over 1 mg BID. Granisetron was well tolerated, and few patients required additional treatment with other antiemetics.

Simultaneous determination of granisetron and 7-hydroxygranisetron in human plasma by high-performance liquid chromatography with fluorescence detection

A highly sensitive high-performance liquid chromatographic method for the determination of granisetron, a novel antiemetic agent for cancer therapy, and its pharmacologically active and major metabolite in human plasma is described. Methylation of the metabolite with trimethylsilyldiazomethane was employed for sample pretreatment. As a result of this treatment, the originally non-fluorescent metabolite could be detected simultaneously with granisetron using fluorescence detection. Both the compounds and the internal standard added were isocratically well resolved from endogenous peaks in plasma on an ODS column. The concentrations of the compounds were proportional to the peak-area ratios over the practical determination ranges of 0.2-100 ng/ml for granisetron and 0.1-50 ng/ml for the metabolite. In tests, reproducibilities for granisetron at 1 ng/ml and the metabolite at 0.5 ng/ml as determined by the relative standard deviation (n = 3) were less than 3.98 and 7.23%, respectively, in a single run.