GnRHR/LHRHR; gonadotropin-releasing hormone receptor (IC50 = 3 nM)

Degarelix exhibits only very weak histamine-releasing properties and has the lowest histamine-releasing capacity among LHRH antagonists, including Cetrorelix, Abarelix, and Ganirelix [1]. Degarelix (1 nM-10 μM, 0-72 hours) reduces cell viability in all prostate cell lines (WPE1-NA22, WPMY-1, BPH-1, VCaP cells), except PC-3 cells [2] . Degarelix (10 μM, 0-72 hours) exerts a direct effect on prostate cell growth through apoptosis [2]. Cell viability assay[2] Cell lines: WPMY-1, WPE1-NA22, BPH-1, LNCaP and VCaP Concentration: 1 nM-10 μM Incubation time: 48 hours and 72 hours for WPMY-1 cells, 72 hours for WPE1-NA22 cells , BPH-1 cells (48 hours and 72 hours), LNCaP cells (48 hours and 72 hours) Results: Cell viability was reduced in all prostate cell lines except PC-3 cells. Apoptosis analysis[2] Cell lines: WPE1-NA22, BPH-1, LNCaP and VCaP Concentration: 10 μM Incubation time: 24, 48 and 72 hours Results: Induced significant increase in caspase 3/7 activation.

Degarelix (0-10 μg/kg; subcutaneous injection; once) reduces plasma LH levels and plasma testosterone levels in castrated rats in a dose-dependent manner [3]. Degarelix is stable when incubated in microsomes and cryopreserved hepatocytes from animal liver tissue. In rats and dogs, the majority of the degarelix dose is eliminated via urine and feces in equal amounts (40-50% in each matrix) within 48 hours, whereas in monkeys the main route of excretion is feces (50 %) and kidney (22%)[4]. Animal model: Male Sprague-Dawley rat, castrated [3] Dosage: 0.3, 1, 3 and 10 μg/kg or 12.5, 50 and 200 μg/kg Administration: subcutaneous injection, once Result: Dose-dependent And the minimum reversible effective dose is 3 μg/kg to reduce plasma LH levels. For the 50 μg/kg and 200 μg/kg doses, absorption t1/2 values were 4 minutes and 30 minutes, Tmax values were 1 hour and 5 hours, and apparent plasma disappearance t1/2 values were 12 hours and 67 hours, respectively. The minimum effective dose is 1 μg/kg, and plasma testosterone levels decrease in a dose-dependent manner.

Assay for Cell Viability [2]
Cell Lines: VCaP, LNCaP, BPH-1, WPMY-1, and WPE1-NA22
Percentage: 1 nM-10 μM
Incubation Time: WPMY-1 cells at 48 and 72h, WPE1-NA22 cells at 72 hours, BPH-1 cells at 48 and 72h, LNCaP cells at 48 and 72h
Result: Reduced cell viability in all prostate cell lines, with the exception of the PC-3 cells.

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Apoptosis Analysis[2]
Cell Line: WPE1-NA22, BPH-1, LNCaP and VCaP
Concentration: 10 μM
Incubation Time: 24, 48 and 72 h
Result: Induced a significant increase on caspase 3/7 activation.

Animal Model: Male Sprague-Dawley rats, castrated[3]
Dosage: 0.3, 1, 3 and 10 μg/kg or 12.5, 50, and 200 μg/kg
Administration: Subcutaneous injection, once
Result: produced a reduction in plasma LH levels that was both reversible and dose-dependent, with a minimum effective dose of 3 μg/kg. Tmax values were 1 and 5 hours, apparent plasma disappearance t1/2 values were 12 and 67 hours, and t1/2 of absorption values were 4 and 30 minutes for the 50 μg/kg and 200 μg/kg doses, respectively.
had a minimum effective dose of 1 μg/kg and caused a dose-dependent drop in plasma testosterone levels.

Absorption, Distribution and Excretion
Following subcutaneous injection, degarelic forms a drug reservoir at the injection site, from which the drug is slowly released into the bloodstream. After a single intravenous bolus of 2 mg/kg, peak plasma concentration of degarelic was reached within 6 hours, at 330 ng/mL. Ki = 0.082 ng/mL, with 93% of receptors completely inhibited; mean residence time (MRT) = 4.5 days. Excretion occurred in feces (70%–80%) and kidneys (20%–30% of the drug was excreted unchanged). Central compartment: 8.88–11.4 L; peripheral compartment: 40.9 L. In patients with prostate cancer, clearance after subcutaneous injection of degarelic was approximately 9 L/hr. Protein binding in mouse, rat, dog, monkey, and human plasma was determined using (3)H-degarelic and ultracentrifugation. Protein binding in animal and human plasma was approximately 90%. The radioactivity distribution of (3)H-degarelk was studied in rats, dogs, and monkeys after administration at doses of 0.03 mg/kg, 0.003 mg/kg, and 0.0082 mg/kg, respectively. Tissue radioactivity was measured after euthanasia and autopsy. High concentrations were primarily observed at the subcutaneous injection site and in excretory organs. Lower drug concentrations, but still higher than plasma concentrations, were typically observed in certain organs of the endocrine and reproductive systems, most of which contain specific receptors for gonadotropin-releasing hormone (LHRH). Higher drug concentrations were also observed in organs rich in reticuloendothelial cells during the elimination phase. No signs of tissue retention were observed. The radioequilibrium following subcutaneous injection of (3)H-degarelk was investigated in rats, dogs, and monkeys. Degarelk is primarily excreted unchanged in the urine and undergoes peptide degradation during elimination via the hepatobiliary pathway in animals and humans. Subcutaneous administration of degarelk creates a local drug reservoir at the injection site, leading to sustained and prolonged release of the active drug. Drug release from the drug reservoir depends on the concentration in the formulation and the volume administered. Furthermore, in repeated-dose studies, increasing the drug concentration in the administered formulation leads to a subproportional increase in peak plasma concentration (Cmax) and area under the plasma concentration-time curve (AUC) within the dosing interval, an increase in trough plasma concentration (Ctrough), and a prolonged terminal half-life (t1/2), thus prolonging the time required to reach steady state, and a tendency for a prolonged time to peak plasma concentration (Tmax). After subcutaneous injection, degarelic forms a drug reservoir at the injection site, from which the drug is slowly released into the bloodstream. Following a single subcutaneous injection of a 240 mg dose (40 mg/mL), peak plasma concentrations of degarelic are typically reached within 2 days. The pharmacokinetic behavior of degarelic is significantly influenced by its concentration in the injection solution. Approximately 90% of the drug is bound to plasma proteins. No quantitatively significant metabolites were detected in plasma after subcutaneous administration. In vitro studies have shown that degarelix is neither a substrate, inducer, nor inhibitor of cytochrome P-450 (CYP) enzymes or the P-glycoprotein transport system. Degarelix elimination is biphasic; in prostate cancer patients, the median terminal half-life after subcutaneous injection of a 240 mg dose (40 mg/mL) is approximately 53 days. Degarelix undergoes peptide hydrolysis during its passage through the hepatobiliary system and is primarily excreted in feces as peptide fragments. Approximately 20-30% of degarelix is excreted by the kidneys after administration, suggesting that approximately 70-80% is excreted via the hepatobiliary system. For more complete data on the absorption, distribution, and excretion of degarelix (6 items in total), please visit the HSDB record page. Metabolites/Metabolites: During its passage through the hepatobiliary system, 70-80% of degarelix undergoes peptide hydrolysis and is then excreted in feces. No active or inactive metabolites are produced, and no CYP450 isoenzymes are involved.
The stability of degarelk was investigated in the liver microsomes of male rats, guinea pigs, rabbits, dogs, monkeys, and humans for up to 60 minutes. No degradation of degarelk was detected in the liver microsomes of rabbits, dogs, monkeys, and humans. A slight trend of degradation of degarelk was observed in the liver microsomes of guinea pigs and rats. Further in vitro metabolism of degarelk was investigated in human liver microsomes for up to 60 minutes. Degarelk has been reported to have a similar metabolic pattern in humans and animals. Degarelk is hardly a substrate for oxidative metabolism, but it is degraded by peptidases to generate various truncated peptides. Low concentrations of only one metabolite were observed in human plasma, and this metabolite was also detected in rats, dogs, and monkeys.
Biological Half-Life
Terminal half-life: 41.5–70.2 days; Absorption half-life: 32.9 hours; Injection site half-life: 1.17 days.
Degarelix is eliminated in a biphasic manner, with a median terminal half-life of approximately 53 days after subcutaneous injection of a 240 mg dose (40 mg/mL) in patients with prostate cancer.

Hepatotoxicity
Degarelix treatment is associated with elevated serum enzymes in up to one-third of patients. However, these elevations are usually mild and self-limiting, resolving spontaneously even without dose adjustment. Less than 1% of patients have ALT values exceeding three times the upper limit of normal. A small number of patients require discontinuation of the drug due to elevated serum enzymes, but no cases of jaundice or clinically significant acute liver injury have been reported in early clinical trials of degarelix. Since its approval and widespread use, despite limitations in the general use of degarelix, no clinically significant cases of liver injury have been reported. Probability Score: E (Unlikely to be the cause of clinically significant liver injury). Protein Binding 90% of the drug is bound to plasma proteins.

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Drug Interactions
Because androgen deprivation therapy may prolong the QTc interval, the safety of degarelix should be carefully evaluated when used in combination with drugs known to prolong the QTc interval or torsades de pointes (e.g., class IA (e.g., quinidine, disopyramide) or class III (e.g., amiodarone, sotalol, dofetilide, ibutilide) antiarrhythmic drugs, methadone, cisapride, moxifloxacin, antipsychotics, etc.).

[1]. An update on the use of degarelix in the treatment of advanced hormone-dependent prostate cancer. Onco Targets Ther. 2013 Apr 16;6:391-402.

[2]. In search of the molecular mechanisms mediating the inhibitory effect of the GnRH antagonistdegarelix on human prostate cell growth. PLoS One. 2015 Mar 26;10(3):e0120670.

[3]. Pharmacological profile of a new, potent, and long-acting gonadotropin-releasing hormoneantagonist: degarelix. J Pharmacol Exp Ther. 2002 Apr;301(1):95-102.

[4]. Metabolite profiles of degarelix, a new gonadotropin-releasing hormone receptor antagonist, in rat, dog, and monkey. Drug Metab Dispos. 2011 Oct;39(10):1895-903.

Degarelc acetate is the acetate form of a long-acting synthetic peptide with gonadotropin-releasing hormone (GnRH) antagonistic activity. Degarelc targets and blocks GnRH receptors on the surface of anterior pituitary gonadotropin-releasing cells, thereby reducing luteinizing hormone (LH) secretion from these cells and consequently decreasing testosterone production by Leydig cells.
See also: Degarelc (containing the active ingredient).
Drug Indications

Degarelc Accord is a gonadotropin-releasing hormone (GnRH) antagonist indicated for the treatment of adult men with advanced hormone-dependent prostate cancer; and for use in combination with radiotherapy for high-risk localized and locally advanced hormone-dependent prostate cancer. For patients with high-risk localized or locally advanced hormone-dependent prostate cancer, Firmagon can be used as neoadjuvant therapy prior to radiotherapy.
FIRMAGON is a gonadotropin-releasing hormone (GnRH) antagonist, indicated for: - treatment of adult men with advanced hormone-dependent prostate cancer. - treatment in combination with radiotherapy for high-risk localized or locally advanced hormone-dependent prostate cancer. - neoadjuvant therapy prior to radiotherapy in patients with high-risk localized or locally advanced hormone-dependent prostate cancer.

C84H107CLN18O18

1692.31

1630.748

C, 60.34; H, 6.36; Cl, 2.17; N, 15.45; O, 15.68

934016-19-0

Degarelix; 214766-78-6;Degarelix-d7;934016-19-0;934246-14-7

16186010

Ac-D-2Nal-D-Phe(4-Cl)-D-3Pal-Ser-Phe(4-S-dihydroorotamido)-D-Phe(4-ureido)-Leu-Lys(iPr)-Pro-D-Ala-NH2.CH3CO2H

XXXSXXLXPA

White to off-white solid powder

18

20

41

121

3420

11

ClC1C=CC(=CC=1)C[C@H](C(N[C@H](CC1C=NC=CC=1)C(N[C@@H](CO)C(N[C@@H](CC1C=CC(=CC=1)NC([C@@H]1CC(NC(N1)=O)=O)=O)C(N[C@H](CC1C=CC(=CC=1)NC(N)=O)C(N[C@@H](CC(C)C)C(N[C@@H](CCCCNC(C)C)C(N1CCC[C@H]1C(N[C@@H](C(N)=O)C)=O)=O)=O)=O)=O)=O)=O)=O)NC([C@@H](CC1C=CC2C=CC=CC=2C=1)NC(C)=O)=O.OC(C)=O

QMBXFMRFTMPFEY-YECCWIQASA-N

InChI=1S/C82H103ClN18O16.C2H4O2.H2O/c1-45(2)35-60(72(107)92-59(16-9-10-33-87-46(3)4)80(115)101-34-12-17-68(101)79(114)88-47(5)70(84)105)93-74(109)63(38-51-23-30-58(31-24-51)91-81(85)116)95-76(111)64(39-50-21-28-57(29-22-50)90-71(106)66-42-69(104)100-82(117)99-66)97-78(113)67(44-102)98-77(112)65(41-53-13-11-32-86-43-53)96-75(110)62(37-49-19-26-56(83)27-20-49)94-73(108)61(89-48(6)103)40-52-18-25-54-14-7-8-15-55(54)36-52;1-2(3)4;/h7-8,11,13-15,18-32,36,43,45-47,59-68,87,102H,9-10,12,16-17,33-35,37-42,44H2,1-6H3,(H2,84,105)(H,88,114)(H,89,103)(H,90,106)(H,92,107)(H,93,109)(H,94,108)(H,95,111)(H,96,110)(H,97,113)(H,98,112)(H3,85,91,116)(H2,99,100,104,117);1H3,(H,3,4);1H2/t47-,59+,60+,61-,62-,63-,64+,65-,66+,67+,68+;;/m1../s1

(4S)-N-[4-[(2S)-2-[[(2S)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-acetamido-3-naphthalen-2-ylpropanoyl]amino]-3-(4-chlorophenyl)propanoyl]amino]-3-pyridin-3-ylpropanoyl]amino]-3-hydroxypropanoyl]amino]-3-[[(2R)-1-[[(2S)-1-[[(2S)-1-[(2S)-2-[[(2R)-1-amino-1-oxopropan-2-yl]carbamoyl]pyrrolidin-1-yl]-1-oxo-6-(propan-2-ylamino)hexan-2-yl]amino]-4-methyl-1-oxopentan-2-yl]amino]-3-[4-(carbamoylamino)phenyl]-1-oxopropan-2-yl]amino]-3-oxopropyl]phenyl]-2,6-dioxo-1,3-diazinane-4-carboxamide;acetic acid;hydrate

FE 200486; FE200486; FE-200486; ASP-3550; ASP 3550; ASP3550; Degarelix acetate; tradename Firmagon

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: ~10 mg/mL (6.1 mM)
H2O: ~5 mg/mL (3.1 mM)

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*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.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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