Difelikefalin HCl

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MedKoo CAT#: 333076

CAS#: 2711717-77-8 (3HCl)

Description: Difelikefalin is a κ-opioid receptor (KOR) agonist. It activates KOR in HEK293 cells expressing the human receptor (EC50 = 0.16 nM in a transactivation assay) and inhibits forskolin-induced cAMP production in R1.G1 mouse thyoma cells (EC50 = 0.048 nM). Difelikefalin is selective for KOR over the μ-opioid receptor (MOR; EC50 = >1 µM in a transactivation assay). It reduces acetic acid-induced writhing, as well as scratching behavior induced by the KOR antagonist GNTI, in mice (ED50s = 0.07 and 0.05 mg/kg, respectively).

Chemical Structure

Difelikefalin HCl
CAS# 2711717-77-8 (3HCl)

Theoretical Analysis

MedKoo Cat#: 333076
Name: Difelikefalin HCl
CAS#: 2711717-77-8 (3HCl)
Chemical Formula: C36H56Cl3N7O6
Exact Mass:
Molecular Weight: 789.237
Elemental Analysis: C, 54.79; H, 7.15; Cl, 13.48; N, 12.42; O, 12.16

Price and Availability

Size Price Availability Quantity
10.0mg USD 450.0 2 Weeks
25.0mg USD 750.0 2 Weeks
50.0mg USD 1250.0 2 Weeks
100.0mg USD 1950.0 2 Weeks
200.0mg USD 2650.0 2 Weeks
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Related CAS #: 1024829-44-4 (acetate)   1024828-77-0 (free base)   2742623-88-5 (TFA)   2711717-77-8 (3HCl)   413256-25-2 (1HCl)    

Synonym: Difelikefalin trihydrochloride; Difelikefalin hydrochloride; Difelikefalin HCl; CR845; CR 845; CR-845; FE 202845; FE202845; FE-202845;

IUPAC/Chemical Name: 1-(D-phenylalanyl-D-phenylalanyl-D-leucyl-D-lysyl)-4-aminopiperidine-4-carboxylic acid trihydrochloride


InChi Code: InChI=1S/C36H53N7O6.3ClH/c1-24(2)21-29(32(45)40-28(15-9-10-18-37)34(47)43-19-16-36(39,17-20-43)35(48)49)42-33(46)30(23-26-13-7-4-8-14-26)41-31(44)27(38)22-25-11-5-3-6-12-25;;;/h3-8,11-14,24,27-30H,9-10,15-23,37-39H2,1-2H3,(H,40,45)(H,41,44)(H,42,46)(H,48,49);3*1H/t27-,28-,29-,30-;;;/m1.../s1

SMILES Code: O=C(C1(N)CCN(C([C@@H](CCCCN)NC([C@@H](CC(C)C)NC([C@@H](CC2=CC=CC=C2)NC([C@@H](CC3=CC=CC=C3)N)=O)=O)=O)=O)CC1)O.[H]Cl.[H]Cl.[H]Cl

Appearance: Solid powder

Purity: >98% (or refer to the Certificate of Analysis)

Shipping Condition: Shipped under ambient temperature as non-hazardous chemical. This product is stable enough for a few weeks during ordinary shipping and time spent in Customs.

Storage Condition: Dry, dark and at 0 - 4 C for short term (days to weeks) or -20 C for long term (months to years).

Solubility: To be determined

Shelf Life: >2 years if stored properly

Drug Formulation: To be determined

Stock Solution Storage: 0 - 4 C for short term (days to weeks), or -20 C for long term (months).

HS Tariff Code: 2934.99.9001

Preparing Stock Solutions

The following data is based on the product molecular weight 789.237 Batch specific molecular weights may vary from batch to batch due to the degree of hydration, which will affect the solvent volumes required to prepare stock solutions.

Recalculate based on batch purity %
Concentration / Solvent Volume / Mass 1 mg 5 mg 10 mg
1 mM 1.15 mL 5.76 mL 11.51 mL
5 mM 0.23 mL 1.15 mL 2.3 mL
10 mM 0.12 mL 0.58 mL 1.15 mL
50 mM 0.02 mL 0.12 mL 0.23 mL

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1: Difelikefalin Acetate. Am J Health Syst Pharm. 2022 Jan 1;79(1):e1-e2. doi: 10.1093/ajhp/zxab377. PMID: 34849553.

2: Shram MJ, Spencer RH, Qian J, Munera CL, Lewis ME, Henningfield JE, Webster L, Menzaghi F. Evaluation of the abuse potential of difelikefalin, a selective kappa-opioid receptor agonist, in recreational polydrug users. Clin Transl Sci. 2021 Oct 28. doi: 10.1111/cts.13173. Epub ahead of print. PMID: 34708917.

3: Deeks ED. Difelikefalin: First Approval. Drugs. 2021 Nov;81(16):1937-1944. doi: 10.1007/s40265-021-01619-6. PMID: 34674115.

4: Inan S, Dun NJ, Cowan A. Antipruritic Effect of Nalbuphine, a Kappa Opioid Receptor Agonist, in Mice: A Pan Antipruritic. Molecules. 2021 Sep 11;26(18):5517. doi: 10.3390/molecules26185517. PMID: 34576988; PMCID: PMC8466557.

5: Pilla JE, Devulapally P. Difelikefalin. 2021 Aug 31. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan–. PMID: 34662080.

6: Viscusi ER, Torjman MC, Munera CL, Stauffer JW, Setnik BS, Bagal SN. Effect of difelikefalin, a selective kappa opioid receptor agonist, on respiratory depression: A randomized, double-blind, placebo-controlled trial. Clin Transl Sci. 2021 Sep;14(5):1886-1893. doi: 10.1111/cts.13042. Epub 2021 Jul 21. PMID: 33982405; PMCID: PMC8504812.

7: Santos-Alonso C, Maldonado Martín M, Sánchez Villanueva R, Álvarez García L, Vaca Gallardo MA, Bajo Rubio MA, Del Peso Gilsanz G, Ossorio González M, Selgas Gutiérrez R. Pruritus in dialysis patients. Review and new perspectives. Nefrologia (Engl Ed). 2021 Mar 8:S0211-6995(21)00032-1. English, Spanish. doi: 10.1016/j.nefro.2020.12.010. Epub ahead of print. PMID: 33707097.

8: Inan S, Cowan A. Antipruritic Effects of Kappa Opioid Receptor Agonists: Evidence from Rodents to Humans. Handb Exp Pharmacol. 2022;271:275-292. doi: 10.1007/164_2020_420. PMID: 33296031.

9: Lipman ZM, Yosipovitch G. An evaluation of difelikefalin as a treatment option for moderate-to-severe pruritus in end stage renal disease. Expert Opin Pharmacother. 2021 Apr;22(5):549-555. doi: 10.1080/14656566.2020.1849142. Epub 2020 Dec 14. PMID: 33190563.

10: Trachtenberg AJ, Collister D, Rigatto C. Recent advances in the treatment of uremic pruritus. Curr Opin Nephrol Hypertens. 2020 Sep;29(5):465-470. doi: 10.1097/MNH.0000000000000625. PMID: 32740217.

11: Vernon M, Ständer S, Munera C, Spencer RH, Menzaghi F. Clinically meaningful change in itch intensity scores: An evaluation in patients with chronic kidney disease-associated pruritus. J Am Acad Dermatol. 2021 Apr;84(4):1132-1134. doi: 10.1016/j.jaad.2020.06.991. Epub 2020 Jun 27. PMID: 32603719.

12: Fishbane S. Difelikefalin in Hemodialysis Patients with Pruritus. Reply. N Engl J Med. 2020 May 21;382(21):2065-2066. doi: 10.1056/NEJMc2002485. PMID: 32433848.

13: Lin CH. Difelikefalin in Hemodialysis Patients with Pruritus. N Engl J Med. 2020 May 21;382(21):2064-2065. doi: 10.1056/NEJMc2002485. PMID: 32433847.

14: Manenti L, Rossi GM, Fiaccadori E. Difelikefalin in Hemodialysis Patients with Pruritus. N Engl J Med. 2020 May 21;382(21):2064. doi: 10.1056/NEJMc2002485. PMID: 32433846.

15: Brennan F, Davison S, Brown M. Difelikefalin in Hemodialysis Patients with Pruritus. N Engl J Med. 2020 May 21;382(21):2064. doi: 10.1056/NEJMc2002485. PMID: 32433845.

16: Lagacé F, Jfri A, Litvinov IV, Netchiporouk E. Newer and Safer Kappa-Opioid Agonist for Your Patients With Uremic Pruritus. J Cutan Med Surg. 2020 Sep/Oct;24(5):525-526. doi: 10.1177/1203475420926989. Epub 2020 May 19. PMID: 32426990.

17: Fishbane S, Mathur V, Germain MJ, Shirazian S, Bhaduri S, Munera C, Spencer RH, Menzaghi F; Trial Investigators. Randomized Controlled Trial of Difelikefalin for Chronic Pruritus in Hemodialysis Patients. Kidney Int Rep. 2020 Jan 28;5(5):600-610. doi: 10.1016/j.ekir.2020.01.006. PMID: 32405581; PMCID: PMC7210745.

18: Steele DJR. Difelikefalin for the Treatment of Uremic Pruritus. N Engl J Med. 2020 Jan 16;382(3):289-290. doi: 10.1056/NEJMe1916598. PMID: 31940704.

19: Fishbane S, Jamal A, Munera C, Wen W, Menzaghi F; KALM-1 Trial Investigators. A Phase 3 Trial of Difelikefalin in Hemodialysis Patients with Pruritus. N Engl J Med. 2020 Jan 16;382(3):222-232. doi: 10.1056/NEJMoa1912770. Epub 2019 Nov 8. PMID: 31702883.

20: Walker G. The opioid crisis: a 21st century pain. Drugs Today (Barc). 2018 Apr;54(4):283-286. doi: 10.1358/dot.2018.54.4.2812620. PMID: 29869649.