GRAPIPRANT

GRAPIPRANT

• Molecular FormulaC₂₆H₂₉N₅O₃S
• Average mass491.605 Da

CAS 415903-37-6

UNII-J9F5ZPH7NB, CJ 023423, CJ-023423,

Phase II, Arrys Therapeutics, CANCER,

PAIN, AskAt Phase II, 

Synonyms and Mappings

• 415903-37-6
• GRAPIPRANT [GREEN BOOK]
• CJ-023
• GRAPIPRANT [INN]
• GRAPIPRANT [WHO-DD]
• MR-10A7
• AAT-007
• MR10A7
• RQ-00000007
• RQ-7
• GRAPIPRANT [USAN]
• GRAPIPRANT
• 2-ETHYL-4,6-DIMETHYL-1-(4-(2-(((((4-METHYLPHENYL)SULFONYL)AMINO)CARBONYL)AMINO)ETHYL)PHENYL)-1H-IMIDAZO(4,5-C)PYRIDINE
• N-(((2-(4-(2-ETHYL-4,6-DIMETHYL-1H-IMIDAZO(4,5-C)PYRIDIN-1-YL)PHENYL)ETHYL)AMINO)CARBONYL)-4-METHYLBENZENESULFONAMIDE
• CJ 023423
• BENZENESULFONAMIDE, N-(((2-(4-(2-ETHYL-4,6-DIMETHYL-1H-IMIDAZO(4,5-C)PYRIDIN-1-YL)PHENYL)ETHYL)AMINO)CARBONYL)-4-METHYL-
• CJ-023,423
• N-(((2-(4-(2-ETHYL-4,6-DIMETHYL-1H-IMIDAZO(4,5-C)PYRIDIN-1-YL)PHENYL)ETHYL)AMINO)CARBONYL)-4-METHYL-BENZENESULFONAMIDE
• CJ-023423

SYN

Arrys Therapeutics (under license from AskAt ) and affiliate Ikena Oncology (formerly known as Kyn Therapeutics ) are developing ARY-007 , an oral formulation of grapiprant, for treating cancers; in December 2019, preliminary data were expected in 2020

Grapiprant (trade name Galliprant) is a small molecule drug that belongs in the piprant class. This analgesic and anti-inflammatory drug is primarily used as a pain relief for mild to moderate inflammation related to osteoarthritis in dogs. Grapiprant has been approved by the FDA’s Center  for Veterinary  Medicine  and was  categorized  as a  non-cyclooxygenase inhibiting non-steroidal anti-inflammatory drug (NSAID) in March 2016.^[1]

Preclinical studies also indicate that grapiprant is not only efficacious as a acute pain but also in chronic pain relief and inflammation drug. The effect of the drug is directly proportional to the dosage and its effects were comparable to human medication such as rofecoxib and piroxicam.^[2]

Grapiprant, a prostanoid EP4 receptor antagonist, is in phase II clinical trials at AskAt for the treatment of chronic pain. Phase I/II clinical trials are ongoing at Arrys Therapeutics in combination with pembrolizumab for the treatment of patients with microsatellite stable colorectal cancer and in patients with advanced or metastatic PD-1/L1 refractory non-small cell lung cancer (NSCLC).

Grapiprant  is also  used  in humans,  and  was researched  to be  used  as a pain  control  and inflammation associated with osteoarthritis. The effect of grapiprant could be explained through the function of prostaglandin E2, in which acts as a pro-inflammatory mediator of redness of the skin, edema and pain which are the typical signs of inflammation. The effect of PGE2 stems from its action through the four prostaglandin receptor subgroups EP1, EP2, EP3 and EP4, in which the prostaglandin EP4 receptor acts as the main intermediary of the prostaglandin-E2-driven inflammation. Grapiprant is widely accepted in veterinary medicine due to its specific and targeted approach to pain management in dogs. The serum concentration of grapiprant is increased when used in conjunction with other drugs such as acetaminophen, albendazole, and alitretinoin.

Common side effects are intestinal related effects such as mild diarrhea, appetite loss, and vomiting.^[3] Additionally, it is found that it might lead to reduced tear production due to it being a sulfa-based medication and also reduced albumin levels.

Grapiprant, a prostanoid EP4 receptor antagonist, is in phase II clinical trials at AskAt for the treatment of chronic pain. Phase I/II clinical trials are ongoing at Arrys Therapeutics in combination with pembrolizumab for the treatment of patients with microsatellite stable colorectal cancer and in patients with advanced or metastatic PD-1/L1 refractory non-small cell lung cancer (NSCLC).

Medical uses

Grapiprant is used once a day as an oral pain relief for dogs with inflammation-related osteoarthritis. It is a non-steroidal anti-inflammatory (NSAID) that functions as a targeted action to treat osteoarthritis pain and inflammation in dogs.

Mechanism of action

Grapiprant acts as a specific antagonist that binds and blocks the prostaglandin EP4 receptor, one out of the four prostaglandin E2 (PGE2) receptor subgroups. The EP4 receptor then mediates the prostaglandin-E2-elicited response to pain, and hence grapiprant was proven to be effective in the decrease of pain in several inflammatory pain models of rats. It was also proven to be effective in reducing osteoarthritis-related pain in humans, which serves as a proof for its mechanism of action. The approximate calculation for  canine efficacy  dose  is between the range of 1.3 and 1.7 mg/kg, in conjunction with a methylcellulose suspending agent. Based on the calculations from the comparisons of binding affinity of grapiprant to the EP4 receptors of  dogs, rats, and humans, the study of plasma and serum protein binding determinations, the effective doses determined in inflammation pain models of rats, and  human-related clinical  studies, it  is  evaluated that  Grapiprant should be administered just once a day. The approved dose of the commercial Grapiprant tablet by the FDA for the pain relief and inflammation associated with osteoarthritis to dogs is reported to be 2 mg/kg a day.^[4]

Absorption

Studies in animals such as horses have shown the presence of Grapiprant in serum 72 hours with a concentration >0.005 ng/ml after the initial administration of a dose of 2 mg/kg. Grapiprant is expeditiously absorbed and the reported serum concentration was reported to be 31.9 ng/ml in an amount of time of 1.5 hours. The actual body exposure to grapiprant after administration of one dose was shown to be 2000 ng.hr/ml. The degree and rate at which grapiprant is absorbed into the body, presents a mean bioavailability of 39%. A significant reduction in the bioavailability, concentration time and maximal concentration were reported to have occurred after food intake.^[1] And thus, grapiprant is usually not administered with food as it will not be as efficient.^[5]

Distribution

The volume of distribution in cat studies was reported to be 918 ml/kg.^[1]

Route of elimination

Following an oral administration, the majority of the dose was metabolized within the first 72 hours. Equine studies have shown that grapiprant is present in urine 96 hours after the first administration of a dose of 2 mg/kg and has a concentration >0.005 ng/ml. From the excreted dose conducted in horses, it is found that 55%, 15% and 19% of the orally-administered dose was excreted in bile, urine, and faeces respectively.^[1]

Toxicity

Safety studies conducted on grapiprant have demonstrated that it generally possesses an exceptional safety profile and a wide safety margin in veterinary studies.^[6] In animal studies, a research on 2.5-12 times overdose was conducted for grapiprant and the study resulted in soft-blobs and mucous-filled faeces, occasional bloody stools and emesis.

PATENT

WO-2020014465

Novel crystalline forms of grapiprant and their salts eg HCl (designated as Form A), useful for inhibiting prostaglandin EP4 receptor activity and treating cancers.

Prostaglandins are mediators of pain, fever and other symptoms associated with inflammation. Prostaglandin E₂ (PGE2) is the predominant eicosanoid detected in inflammation conditions. In addition, it is also involved in various physiological and/or pathological conditions such as hyperalgesia, uterine contraction, digestive peristalsis, awakeness, suppression of gastric acid secretion, blood pressure, platelet function, bone metabolism, angiogenesis or the like.

[0003] Four PGE2 receptor subtypes (EP1, EP2, EP3 and EP4) displaying different pharmacological properties exist. The EP4 subtype, a Gs-coupled receptor, stimulates cAMP production as well as PI3K and GSK3P signaling, and is distributed in a wide variety of tissue suggesting a major role in PGE2-mediated biological events. Various EP4 inhibitors have been described previously, for example, in WO 2002/032900, WO 2005/021508, EiS 6,710,054, and US 7,238,714, the contents of which are incorporated herein by reference in their entireties.

[0004] Accordingly, there is a need for treating, preventing, and/or reducing severity of a proliferative disorder associated with prostaglandin EP4 receptor activity. The present invention addresses such a need.

It has now been found that compounds of the present invention, and compositions thereof, are useful for treating, preventing, and/or reducing severity of a proliferative disorder associated with prostaglandin EP4 receptor activity. In general, salt forms and co-crystal forms, and pharmaceutically acceptable compositions thereof, are useful for treating or lessening the severity of proliferative disorders associated with prostaglandin EP4 receptor activity, as described in detail herein. Such compounds are represented by the chemical structure below, denoted as compound A (also known as grapiprant):

A

or a pharmaceutically acceptable salt thereof.

United States Patent 7,960,407, filed March 1, 2006 and issued June 14, 2011 (“the ‘407 patent,” the entirety of which is hereby incorporated herein by reference), describes certain EP4 inhibitor compounds. Such compounds include compound A:

or a pharmaceutically acceptable salt thereof.

[0037] Compound A, N-[({2-[4-(2-Ethyl-4,6-dimethyl-lH-imidazo[4,5-c]pyridin-l-yl) phenyl]ethyl}amino)carbonyl]-4-methylbenzenesulfonamide, is described in detail in the ‘407

patent, including its synthetic route. The ‘407 patent also discloses a variety of physical forms of compound A.

[0038] It would be desirable to provide a solid form of compound A (e.g., as a co-crystal thereof or salt thereof) that imparts characteristics such as improved aqueous solubility, stability and ease of formulation. Accordingly, the present invention provides both co-crystal forms and salt forms of compound A:

A.

PATENT

WO 2002032900

PATENT

WO 2002032422

Family members of the product case ( WO0232422 ) of grapiprant have protection in most of the EU states until October 2021 and expire in the US in October 15, 2021.

PATENT

WO 2003086371

PATENT

WO2020014445 covering combinations of grapiprant and an immuno-oncology agent.

WO 2005102389

WO 2006095268

US 7960407

US 20190314390

References

Grapiprant

Clinical data
Trade names	Galliprant
Routes of administration	Oral
ATCvet code	QM01AX92 (WHO)
Pharmacokinetic data
Bioavailability	6.6 L/kg, high volume of distribution
Elimination half-life	5.86 hours in horses
Excretion	Urine
Identifiers
IUPAC name[show]
CAS Number	415903-37-6
PubChem CID	11677589
DrugBank	DB12836
ChemSpider	9852318
UNII	J9F5ZPH7NB
CompTox Dashboard (EPA)	DTXSID60194419
Chemical and physical data
Formula	C26H29N5O3S
Molar mass	491.61 g·mol−1
3D model (JSmol)	Interactive image
SMILES[hide] CCC1=NC2=C(C)N=C(C)C=C2N1C1=CC=C(CCNC(=O)NS(=O)(=O)C2=CC=C(C)C=C2)C=C1

//////////////GRAPIPRANT, 415903-37-6, UNII-J9F5ZPH7NB, CJ 023423, CJ-023423, RQ-00000007, MR10A7, Galliprant, Phase II, Arrys Therapeutics, CANCER, PAIN, AskAt

CCC1=NC2=C(N1C3=CC=C(C=C3)CCNC(=O)NS(=O)(=O)C4=CC=C(C=C4)C)C=C(N=C2C)C