Setmelanotide

Setmelanotide

Ac-Arg-Cys(1)-D-Ala-His-D-Phe-Arg-Trp-Cys(1)-NH2

• Molecular FormulaC₄₉H₆₈N₁₈O₉S₂
• Average mass1117.309 Da
• N-acetyl-L-arginyl-L-cysteinyl-D-alanyl-L-histidyl-D-phenylalanyl-L-arginyl-L-tryptophyl-L-cysteinamide (2->8)-disulfide

FDA 11/25/2020, Imcivree, To treat obesity and the control of hunger associated with pro-opiomelanocortin deficiency, a rare disorder that causes severe obesity that begins at an early age
Drug Trials Snapshot, 10MG/ML, SOLUTION;SUBCUTANEOUS, Orphan

DESCRIPTION

IMCIVREE contains setmelanotide acetate, a melanocortin 4 (MC4) receptor agonist. Setmelanotide is an 8 amino acid cyclic peptide analog of endogenous melanocortin peptide α-MSH (alpha-melanocyte stimulating hormone).

The chemical name for setmelanotide acetate is acetyl-L-arginyl-L-cysteinyl-D-alanyl-Lhistidinyl-D-phenylalanyl-L-arginyl-L-tryptophanyl-L-cysteinamide cyclic (2→8)-disulfide acetate. Its molecular formula is C₄₉H₆₈N₁₈O₉S₂ (anhydrous, free-base), and molecular mass is 1117.3 Daltons (anhydrous, free-base).

The chemical structure of setmelanotide is:

 

IMCIVREE injection is a sterile clear to slightly opalescent, colorless to slightly yellow solution. Each 1 mL of IMCIVREE contains 10 mg of setmelanotide provided as setmelanotide acetate, which is a salt with 2 to 4 molar equivalents of acetate, and the following inactive ingredients: 100 mg N-(carbonyl-methoxypolyethylene glycol 2000)-1,2-distearoyl-glycero-3phosphoethanolamine sodium salt, 8 mg carboxymethylcellulose sodium (average MWt 90,500), 11 mg mannitol, 5 mg phenol, 10 mg benzyl alcohol, 1 mg edetate disodium dihydrate, and Water for Injection. The pH of IMCIVREE is 5 to 6.

Setmelanotide is a peptide drug and investigational anti-obesity medication which acts as a selective agonist of the MC4 receptor. Setmelanotide binds to and activates MC4 receptors in the paraventricular nucleus (PVN) of the hypothalamus and in the lateral hypothalamic area (LHA), areas involved in the regulation of appetite, and this action is thought to underlie its appetite suppressant effects. Setmelanotide increases resting energy expenditure in both obese animals and humans. Setmelanotide has been reported to possess the following activity profile (cAMP, EC50): MC4 (0.27 nM) > MC3 (5.3 nM) ≈ MC1 (5.8 nM) > MC5 (1600 nM) ≟ MC2 (>1000 nM).

Setmelanotide, sold under the brand name Imcivree, is a medication for the treatment of obesity.^[1]

The most common side effects include injection site reactions, skin hyperpigmentation (skin patches that are darker than surrounding skin), headache and gastrointestinal side effects (such as nausea, diarrhea, and abdominal pain), among others.^[1] Spontaneous penile erections in males and adverse sexual reactions in females have occurred with treatment.^[1] Depression and suicidal ideation have also occurred with setmelanotide.^[1]

SYN

WO 2011060355

Medical uses

Setmelanotide is indicated for chronic weight management (weight loss and weight maintenance for at least one year) in people six years and older with obesity due to three rare genetic conditions: pro-opiomelanocortin (POMC) deficiency, proprotein subtilisin/kexin type 1 (PCSK1) deficiency, and leptin receptor (LEPR) deficiency confirmed by genetic testing demonstrating variants in POMC, PCSK1, or LEPR genes considered pathogenic (causing disease), likely pathogenic, or of uncertain significance.^[1] Setmelanotide is the first FDA-approved treatment for these genetic conditions.^[1]

Setmelanotide is not approved for obesity due to suspected POMC, PCSK1, or LEPR deficiency with variants classified as benign (not causing disease) or likely benign or other types of obesity, including obesity associated with other genetic syndromes and general (polygenic) obesity.^[1]

Setmelanotide binds to and activates MC₄ receptors in the paraventricular nucleus (PVN) of the hypothalamus and in the lateral hypothalamic area (LHA), areas involved in the regulation of appetite, and this action is thought to underlie its appetite suppressant effects.^[2] In addition to reducing appetite, setmelanotide increases resting energy expenditure in both obese animals and humans.^[3] Importantly, unlike certain other MC₄ receptor agonists, such as LY-2112688, setmelanotide has not been found to produce increases in heart rate or blood pressure.^[4]

Setmelanotide has been reported to possess the following activity profile (cAMP, EC₅₀): MC₄ (0.27 nM) > MC₃ (5.3 nM) ≈ MC₁ (5.8 nM) > MC₅ (1600 nM) ≟ MC₂ (>1000 nM).^[5] (19.6-fold selectivity for MC₄ over MC₃, the second target of highest activity.)

History

Setmelanotide was evaluated in two one-year studies.^[1] The first study enrolled participants with obesity and confirmed or suspected POMC or PCSK1 deficiency while the second study enrolled participants with obesity and confirmed or suspected LEPR deficiency; all participants were six years or older.^[1] The effectiveness of setmelanotide was determined by the number of participants who lost more than ten percent of their body weight after a year of treatment.^[1]

The effectiveness of setmelanotide was assessed in 21 participants, ten in the first study and eleven in the second.^[1] In the first study, 80 percent of participants with POMC or PCSK1 deficiency lost ten percent or more of their body weight.^[1] In the second study, 46 percent of participants with LEPR deficiency lost ten percent or more of their body weight.^[1]

The study also assessed the maximal (greatest) hunger in sixteen participants over the previous 24 hours using an eleven-point scale in participants twelve years and older.^[1] In both studies, some, but not all, of participants’ weekly average maximal hunger scores decreased substantially from their scores at the beginning of the study.^[1] The degree of change was highly variable among participants.^[1]

The U.S. Food and Drug Administration (FDA) granted the application for setmelanotide orphan disease designation, breakthrough therapy designation, and priority review.^[1] The FDA granted the approval of Imcivree to Rhythm Pharmaceutical, Inc.^[1]

Research

Setmelanotide is a peptide drug and investigational anti-obesity medication which acts as a selective agonist of the MC₄ receptor.^[6][4] Its peptide sequence is Ac-Arg-Cys(1)-D-Ala-His-D-Phe-Arg-Trp-Cys(1)-NH2. It was first discovered at Ipsen and is being developed by Rhythm Pharmaceuticals for the treatment of obesity and diabetes.^[6] In addition, Rhythm Pharmaceuticals is conducting trials of setmelanotide for the treatment of Prader–Willi syndrome (PWS), a genetic disorder which includes MC₄ receptor deficiency and associated symptoms such as excessive appetite and obesity.^[7] As of December 2014, the drug is in phase II clinical trials for obesity and PWS.^{[6][8][9][needs update]} So far, preliminary data has shown no benefit of Setmelanotide in Prader-Willi syndrome.^[10]

PATENT

WO 2007008704

WO 2011060355

WO 2011060352

US 20120225816

PAPER

Journal of Medicinal Chemistry, 61(8), 3674-3684; 2018

PATENT

https://patents.google.com/patent/US9314509

Synthesis of Example 1i.e., Ac-Arg-cyclo(Cys-D-Ala-His-D-Phe-Arg-Trp-Cys)-NH₂

The title peptide having the above structure was assembled using Fmoc chemistry on an Apex peptide synthesizer (Aapptec; Louisville, Ky., USA). 220 mg of 0.91 mmol/g (0.20 mmoles) Rink Amide MBHA resin (Polymer Laboratories; Amherst, Mass., USA) was placed in a reaction well and pre-swollen in 3.0 mL of DMF prior to synthesis. For cycle 1, the resin was treated with two 3-mL portions of 25% piperidine in DMF for 5 and 10 minutes respectively, followed by 4 washes of 3-mL DMF—each wash consisting of adding 3 mL of solvent, mixing for 1 minute, and emptying for 1 minute. Amino acids stocks were prepared in NMP as 0.45M solutions containing 0.45M HOBT. HBTU was prepared as a 0.45M solution in NMP and DIPEA was prepared as a 2.73M solution in NMP. To the resin, 2 mL of the first amino acid (0 9 mmoles, Fmoc-Cys(Trt)-OH) (Novabiochem; San Diego, Calif., USA) was added along with 2 mL (0.9 mmoles) of HBTU and 1.5 mL (4.1 mmoles) of DIPEA. After one hour of constant mixing, the coupling reagents were drained from the resin and the coupling step was repeated. Following amino acid acylation, the resin was washed with two 3-mL aliquots of DMF for 1 minute. The process of assembling the peptide (deblock/wash/acylate/wash) was repeated for cycles 2-9 identical to that as described for cycle 1. The following amino acids were used: cycle 2) Fmoc-Trp(Boc)-OH (Genzyme; Cambridge, Mass., USA); cycle 3) Fmoc-Arg(Pbf)-OH (Novabiochem); cycle 4) Fmoc-DPhe-OH (Genzyme); cycle 5) Fmoc-His(Trt)-OH (Novabiochem); cycle 6) Fmoc-D-Ala-OH (Genzyme); cycle 7) Fmoc-Cys(Trt)-OH, (Novabiochem); and cycle 8) Fmoc-Arg(Pbf)-OH (Genzyme). The N-terminal Fmoc was removed with 25% piperidine in DMF as described above, followed by four 3-mL DMF washes for 1 minute. Acetylation of the N-terminus was performed by adding 0.5 mL of 3M DIPEA in NMP to the resin along with 1.45 mL of 0.45M acetic anhydride in NMP. The resin was mixed for 30 minutes and acetylation was repeated. The resin was washed with 3 mL of DMF for a total of 5 times followed with 5 washes with 5 mL of DCM each.

To cleave and deprotect the peptide, 5mL of the following reagent was added to the resin: 2% TIS/5% water/5% (w/v) DTT/88% TFA. The solution was allowed to mix for 3.5 hours. The filtrate was collected into 40 mL of cold anhydrous ethyl ether. The precipitate was pelleted for 10 minutes at 3500 rpm in a refrigerated centrifuge. The ether was decanted and the peptide was re-suspended in fresh ether. The ether workup was performed three times. Following the last ether wash, the peptide was allowed to air dry to remove residual ether.

The peptide was dissolved in 10% acetonitrile and analyzed by mass spectrometry and reverse-phase HPLC employing a 30×4.6 cm C18 column (Vydac; Hesperia, Calif., USA) with a gradient of 2-60% acetonitrile (0.1% TFA) over 30 minutes. This analysis identified a product with ˜53% purity. Mass analysis employing electrospray ionization identified a main product containing a mass of 1118.4 corresponding to the desired linear product. The crude product (˜100 mg) was diluted to a concentration of 2 mg/mL in 5% acetic acid. To this solution, 0.5M iodine/methanol was added dropwise with vigorous stirring until a pale yellow color was achieved. The solution was vigorously stirred for another 10 minutes. Excess iodine was then quenched by adding 1.0M sodium thiosulfate under continuous mixing until the mixture was rendered colorless. The peptide was re-examined by mass spectrometry analysis and HPLC. Mass spectrometry analysis identified a main species with a mass of 1116.4 which indicated successful oxidation to form the cyclic peptide. The peptide solution was purified on a preparative HPLC equipped with a C18 column using a similar elution gradient. The purified product was re-analyzed by HPLC for purity (>95%) and mass spectrometry (1116.9 which is in agreement with the expected mass of 1117.3) and subsequently lyophilized. Following lyophilization, 28 mg of purified product was obtained representing a 24% yield.

The other exemplified peptides were synthesized substantially according to the procedure described for the above-described synthetic process. Physical data for select exemplified peptides are given in Table 1.

TABLE 1 Example Mol. Wt. Mol. Wt. Purity Number (calculated) (ES-MS) (HPLC) 1 1117.3 1116.9 95.1% 2 1117.3 1116.8 99.2% 3 1280.5 1280.6 98.0% 5 1216.37 1216.20 99.9%

Preparation of Pamoate Salt of Example 1

The acetate salt of Example 1 (200 mg, 0.18 mmole) was dissolved in 10 mL of water. Sodium pamoate (155 mg, 0.36 mmole) was dissolved in 10 mL of water. The two solutions were combined and mixed well. The precipitates were collected by centrifugation at 3000 rpm for 20 minutes, washed for three times with water, and dried by lyophilization.

References

External links

• “Setmelanotide”. Drug Information Portal. U.S. National Library of Medicine.

Setmelanotide

Clinical data
Trade names	Imcivree
Other names	RM-493; BIM-22493; IRC-022493; N2-Acetyl-L-arginyl-L-cysteinyl-D-alanyl-L-histidyl-D-phenylalanyl-L-arginyl-L-tryptophyl-L-cysteinamide, cyclic (2-8)-disulfide
ATC code	None
Legal status
Legal status	US: ℞-only
Identifiers
IUPAC name[show]
CAS Number	920014-72-8
PubChem CID	11993702
ChemSpider	10166169
UNII	N7T15V1FUY
KEGG	D11927
Chemical and physical data
Formula	C49H68N18O9S2
Molar mass	1117.32 g·mol−1
3D model (JSmol)	Interactive image
SMILES[hide] C[C@@H]1C(=O)N[C@H](C(=O)N[C@@H](C(=O)N[C@H](C(=O)N[C@H](C(=O)N[C@@H](CSSC[C@@H](C(=O)N1)NC(=O)[C@H](CCCN=C(N)N)NC(=O)C)C(=O)N)Cc2c[nH]c3c2cccc3)CCCN=C(N)N)Cc4ccccc4)Cc5cnc[nH]5
InChI[hide] InChI=1S/C49H68N18O9S2/c1-26-41(70)63-37(20-30-22-55-25-59-30)46(75)64-35(18-28-10-4-3-5-11-28)44(73)62-34(15-9-17-57-49(53)54)43(72)65-36(19-29-21-58-32-13-7-6-12-31(29)32)45(74)66-38(40(50)69)23-77-78-24-39(47(76)60-26)67-42(71)33(61-27(2)68)14-8-16-56-48(51)52/h3-7,10-13,21-22,25-26,33-39,58H,8-9,14-20,23-24H2,1-2H3,(H2,50,69)(H,55,59)(H,60,76)(H,61,68)(H,62,73)(H,63,70)(H,64,75)(H,65,72)(H,66,74)(H,67,71)(H4,51,52,56)(H4,53,54,57)/t26-,33+,34+,35-,36+,37+,38+,39+/m1/s1 Key:HDHDTKMUACZDAA-PHNIDTBTSA-N

///////////Setmelanotide, FDA 2020, 2020 APPROVALS, Imcivree, Orphan, PEPTIDE, ANTIOBESITY, UNII-N7T15V1FUY, сетмеланотид , سيتميلانوتيد , 司美诺肽 , BIM 22493, RM 493

CC1C(=O)NC(C(=O)NC(C(=O)NC(C(=O)NC(C(=O)NC(CSSCC(C(=O)N1)NC(=O)C(CCCN=C(N)N)NC(=O)C)C(=O)N)CC2=CNC3=CC=CC=C32)CCCN=C(N)N)CC4=CC=CC=C4)CC5=CN=CN5