5-HT3 Receptor ( IC50 = 17 μM )

GR exhibited an IC50 of 17/± 6 uM in rat forestomach, reducing 5-HT-induced contractions. GR decreased s-HT tachycardia in isolated rabbit hearts in a dose-dependent manner with a range of 0.003-0.03 nM; high GR levels also decreased submaximal and maximum responses to 5-HT [1].

Six and 72 hours after the development of inflammation, granisetron dose-dependently reduced leukocyte accumulation. PGE(2) levels were elevated by Granisetron at lower dosages (50 μg/bag), but release was suppressed at higher doses (100 and 200 μg/bag). Concurrently, granisetron at lower doses will decrease TNFα production, but granisetron at higher doses will enhance TNFα production; these two effects are reciprocal [2]. It was demonstrated that GTDS was not inferior to oral granisetron: 65% of patients receiving oral granisetron and 60% of patients receiving GTDS obtained complete control (treatment difference, -5%; 95% confidence range, -13-3). Constipation was the most frequent side effect of both well-tolerated therapies [3].

The activity of BRL 43694 (granisetron) was investigated using established models of 5-HT3 receptor activity. In guinea-pig isolated ileum, BRL 43694 antagonised the contractions evoked by relatively high concentrations of 5-HT (pA2 = 8.1 +/- 0.2). However, except in high concentrations, BRL 43694 did not affect the contractions of similar preparations of ileum, evoked by electrical field stimulation (cholinergically mediated), the nicotinic agonist dimethylphenyl piperazinium (DMPP) or by cholecystokinin octapeptide. Similarly, BRL 43694 did not affect electrically evoked, cholinergically mediated contractions of rat or human isolated stomach. In other models of 5-HT3 receptor activity (rabbit isolated heart, Bezold-Jarisch reflex in anaesthetised rats), potent antagonism by BRL 43694 was demonstrated. In radioligand binding studies on rat brain membranes, BRL 43694 had little or no affinity for 5-HT1A, 5-HT1B, 5-HT2 or for many other binding sites. BRL 43694 may therefore be a potent and selective 5-HT3 receptor antagonist[1].

The antagonists of 5HT(3) receptors have shown impressive efficacy in rheumatoid arthritis, osteoarthritis or fibromyalgia. The mechanistic relationships between 5HT(3) receptors, angiogenesis and sequence of cytokine expression, and leukocyte recruitment during inflammation are not clear. We evaluate the effects of granisetron on inflammatory parameters and angiogenesis in rat air-pouch model. Methods: Male Wistar rats were anesthetized, and then 20 ml and 10 ml of sterile air were injected subcutaneously in the back on day 0 and day 3, respectively. On day 6, inflammation was induced by injection of 1 ml of carrageenan 1% into pouches. After 6 and 72 h, the rats were sacrificed; pouch fluid was collected in order to determine exudate volume, the number of accumulated cells and TNFalpha/PGE(2) concentration. Pouches were dissected out and weighed. Angiogenesis of granulomatous tissue was assayed using a hemoglobin kit. Results: Leukocyte accumulation was dose-dependently inhibited by granisetron both at 6 and 72 h after induction of inflammation. All doses of granisetron decreased hemoglobin level in the whole granulation tissue in a bell-shaped manner. Vascular network formation was also inhibited by granisetron. Granisetron increased PGE(2) level at a lower dose (50 microg/pouch) but higher doses (100 and 200 microg/pouch) inhibited the release. At the same time, TNFalpha production was decreased by the lower dose and increased by higher doses of granisetron in a reciprocal fashion. Conclusions: Anti-inflammatory activities of 5HT(3) receptor antagonist, granisetron probably are mediated through modulation of TNFalpha/PGE(2) production and leukocyte infiltration[2].

Absorption, Distribution and Excretion
Absorption of is rapid and complete, though oral bioavailability is reduced to about 60% as a result of first pass metabolism.
The remainder of the dose is excreted as metabolites, 48% in the urine and 38% in the feces.
0.52 L/h/kg [Cancer Patients with 1 mg bid for 7 days]
0.41 L/h/kg [Healthy subject with a single 1 mg dose]

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Metabolism / Metabolites
Primarily hepatic; undergoes N -demethylation and aromatic ring oxidation followed by conjugation. Animal studies suggest that some of the metabolites may have 5-HT 3 receptor antagonist activity.
Granisetron has known human metabolites that include 7-Hydroxygranisetron and 9'-Desmethylgranisetron.

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Biological Half-Life
4-6 hours in healthy patients, 9-12 hours in cancer patients

Effects During Pregnancy and Lactation
◉ Summary of Use during Lactation
No information is available on the use of granisetron during breastfeeding. Until more data become available, granisetron should be used with caution during breastfeeding. An alternate drug may be preferred.
◉ Effects in Breastfed Infants
Relevant published information was not found as of the revision date.
◉ Effects on Lactation and Breastmilk
A woman nursing an 8-month-old infant 6 to 8 times daily was admitted to the hospital for an appendectomy. During the procedure she received granisetron, cefazolin, ketorolac, rocuronium, succinylcholine, and sufentanil. The patient also received 2 boluses of intravenous propofol of 150 mg followed shortly thereafter by a 50 mg dose. Postoperatively, she was receiving acetaminophen, cefazolin, ibuprofen, and pantoprazole, as well as oxycodone and dimenhydrinate as needed. Twenty-two hours after the procedure, the mother extracted milk for the first time and noted it to be light green in color. Analysis of the green milk using a nonvalidated assay detected no propofol. The green color faded and was absent by postoperative day 4 when she resumed breastfeeding. The authors judged that the green color was possibly caused by propofol or one of its metabolites.

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Protein Binding
65%

[1]. Sanger GJ, Nelson DR. Selective and functional 5-hydroxytryptamine3 receptor antagonism by BRL 43694 (granisetron). Eur J Pharmacol. 1989 Jan 10;159(2):113-24.

[2]. Maleki-Dizaji N, Eteraf-Oskouei T, Fakhrjou A, The effects of 5HT3 receptor antagonist granisetron on inflammatory parameters and angiogenesis in the air-pouch model of inflammation. Int Immunopharmacol. 2010 Sep;10(9):1010-6.

[3]. Boccia RV, Gordan LN, Clark G, Efficacy and tolerability of transdermal granisetron for the control of chemotherapy-induced nausea and vomiting associated with moderately and highly emetogenic multi-day chemotherapy: a randomized, double-blind, phase III.

Granisetron is a monocarboxylic acid amide resulting from the formal condensation of the carboxy group of 1-methyl-1H-indazole-3-carboxylic acid with the primary amino group of (3-endo)-9-methyl-9-azabicyclo[3.3.1]nonan-3-amine. A selective 5-HT3 receptor antagonist, it is used (generally as the monohydrochloride salt) to manage nausea and vomiting caused by cancer chemotherapy and radiotherapy, and to prevent and treat postoperative nausea and vomiting. It has a role as a serotonergic antagonist and an antiemetic. It is a member of indazoles, a monocarboxylic acid amide and a tertiary amino compound.
A serotonin receptor (5HT-3 selective) antagonist that has been used as an antiemetic and antinauseant for cancer chemotherapy patients.
Granisetron is a Serotonin-3 Receptor Antagonist. The mechanism of action of granisetron is as a Serotonin 3 Receptor Antagonist.
Granisetron is an indazole derivative with antiemetic properties. As a selective serotonin receptor antagonist, granisetron competitively blocks the action of serotonin at 5-hydroxytryptamine3 (5-HT3) receptors, resulting in the suppression of chemotherapy- and radiotherapy-induced nausea and vomiting.
APF530 is a controlled-release formulation of a biodegradable poly(ortho ester) polymer, encapsulating the indazole derivative granisetron, with antiemetic activity. Upon administration of APF530, the polymer slowly erodes and releases the active ingredient granisetron. As a selective serotonin receptor antagonist, granisetron competitively blocks the action of serotonin at 5-hydroxytryptamine3 (5-HT3) receptors, resulting in the suppression of nausea and vomiting over a sustained period of time.
A serotonin receptor (5HT-3 selective) antagonist that has been used as an antiemetic for cancer chemotherapy patients.
See also: Granisetron (annotation moved to).

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Drug Indication
For the prevention of nausea and vomiting associated with initial and repeat courses of emetogenic cancer therapy (including high dose cisplatin), postoperation, and radiation (including total body irradiation and daily fractionated abdominal radiation).
FDA Label
Prevention of nausea and vomiting in patients receiving moderately or highly emetogenic chemotherapy, with or without cisplatin, for up to five consecutive days. Sancuso may be used in patients receiving their first chemotherapy regimen or in patients who have previously received chemotherapy.

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Mechanism of Action
Granisetron is a potent, selective antagonist of 5-HT₃ receptors. The antiemetic activity of the drug is brought about through the inhibition of 5-HT3 receptors present both centrally (medullary chemoreceptor zone) and peripherally (GI tract). This inhibition of 5-HT3 receptors in turn inhibits the visceral afferent stimulation of the vomiting center, likely indirectly at the level of the area postrema, as well as through direct inhibition of serotonin activity within the area postrema and the chemoreceptor trigger zone.

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Pharmacodynamics
Granisetron is a selective inhibitor of type 3 serotonergic (5-HT₃) receptors. Granisetron has little or no affinity for other serotonin receptors, including 5-HT 1 , 5-HT 1A , 5-HT 1B/C , or 5-HT 2 ; for alpha 1 -, alpha 2 -, or beta-adrenoreceptors; for dopamine D 2 receptors; for histamine H 1 receptors; for benzodiazepine receptors; for picrotoxin receptors; or for opioid receptors. In most human studies, granisetron has had little effect on blood pressure, heart rate, or electrocardiogram (ECG). The drug is structurally and pharmacologically related to ondansetron, another selective inhibitor of 5-HT₃ receptors. The serontonin 5-HT₃ receptors are located on the nerve terminals of the vagus in the periphery, and centrally in the chemoreceptor trigger zone of the area postrema. The temporal relationship between the emetogenic action of emetogenic drugs and the release of serotonin, as well as the efficacy of antiemetic agents suggest that chemotherapeutic agents release serotonin from the enterochromaffin cells of the small intestine by causing degenerative changes in the GI tract. The serotonin then stimulates the vagal and splanchnic nerve receptors that project to the medullary vomiting center, as well as the 5-HT3 receptors in the area postrema, thus initiating the vomiting reflex, causing nausea and vomiting.

C18H24N4O

312.40936

312.195

C, 69.20; H, 7.74; N, 17.93; O, 5.12

109889-09-0

Granisetron Hydrochloride;107007-99-8;Granisetron-d3;1224925-64-7

5284566

White to off-white solid powder

1.3±0.1 g/cm3

532.0±40.0 °C at 760 mmHg

275.6±27.3 °C

0.0±1.4 mmHg at 25°C

1.690

1.47

1

3

2

23

442

2

CN1[C@@H]2CCC[C@H]1CC(C2)NC(=O)C3=NN(C4=CC=CC=C43)C

MFWNKCLOYSRHCJ-AGUYFDCRSA-N

InChI=1S/C18H24N4O/c1-21-13-6-5-7-14(21)11-12(10-13)19-18(23)17-15-8-3-4-9-16(15)22(2)20-17/h3-4,8-9,12-14H,5-7,10-11H2,1-2H3,(H,19,23)/t12?,13-,14+

1-methyl-N-[(1R,5S)-9-methyl-9-azabicyclo[3.3.1]nonan-3-yl]indazole-3-carboxamide

granisetron; 109889-09-0; Sancuso; Sustol; Kevatril; BRL-43694; Granisetronum; APF530;

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO : ~25 mg/mL (~80.02 mM)

Solubility in Formulation 1: ≥ 2.5 mg/mL (8.00 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 2.5 mg/mL (8.00 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.

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Solubility in Formulation 3: ≥ 2.5 mg/mL (8.00 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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 (Please use freshly prepared in vivo formulations for optimal results.)