1. Membrane Transporter/Ion Channel
  2. P2X Receptor

Gefapixant (Synonyms: AF219; MK-7264)

Cat. No.: HY-101588
Handling Instructions

Gefapixant is an orally active P2X3 receptor (P2X3R) antagonist with IC 50s of ~30 nM versus recombinant hP2X3 homotrimers and 100-250 nM at hP2X2/3 heterotrimeric receptors.

For research use only. We do not sell to patients.

Gefapixant Chemical Structure

Gefapixant Chemical Structure

CAS No. : 1015787-98-0

Size Stock
250 mg Get quote
500 mg Get quote

* Please select Quantity before adding items.

Customer Review

  • Biological Activity

  • Protocol

  • Technical Information

  • Purity & Documentation

  • References


Gefapixant is an orally active P2X3 receptor (P2X3R) antagonist with IC 50s of ~30 nM versus recombinant hP2X3 homotrimers and 100-250 nM at hP2X2/3 heterotrimeric receptors.

IC50 & Target

IC50: ~30 nM (recombinant hP2X3 homotrimers), 100-250 nM (hP2X2/3 heterotrimeric receptors)[1].

In Vitro

The aryloxy-pyrimidinediamine, Gefapixant (AF-219) is an orally active small molecule antagonist at human P2X3-containing receptors. The IC50 of Gefapixant has been reported as ~30 nM versus recombinant hP2X3 homotrimers and 100-250 nM at hP2X2/3 heterotrimeric receptors, potencies very similar to those reported for recombinant rat receptors, and it displays no inhibitory impact on any non-P2X3 subunit containing receptors (IC50 values>>10,000 nM at recombinant homotrimeric hP2X1, hP2X2, hP2X4, rP2X5 and hP2X7 channels)[1].

In Vivo

In an adjuvant-induced rthritis model in rat (7d following intraplantar administration of complete Freund's adjuvant), AF-353 produces dose-dependent antihyperalgesia in weight-bearing asymmetry and von Frey filament mechanical tests; magnitude of effect is compared with that of the NSAID naproxen. In a rat model of knee osteoarthritis (14d following intra-articular administration of monoiodoacetate), Gefapixant (7d bid, orally; right) attenuates the weight bearing laterality with complete reversal of apparent hyperalgesia at the two higher doses[2].

Clinical Trial
Solvent & Solubility
In Vitro: 

10 mM in DMSO

Stock Solutions
Concentration Solvent Mass 1 mg 5 mg 10 mg
1 mM 2.8297 mL 14.1483 mL 28.2965 mL
5 mM 0.5659 mL 2.8297 mL 5.6593 mL
10 mM 0.2830 mL 1.4148 mL 2.8297 mL
*Please refer to the solubility information to select the appropriate solvent.
Animal Administration

A rodent model often employs for assessing potential for drug effect in osteoarthritis (OA) pain is based on intraarticular injection of monoiodoacetate (mIOA) into one knee joint of the rat. Progressive loss of chondrocytes leads to histological changes of the articular cartilage over subsequent weeks that resemble the changes which occur in human OA, leading to joint discomfort exemplified by a shift in the weight distribution (asymmetry) to favor the unaffected limb. To measure the effect of Gefapixant on the weight bearing laterality and apparent hyperalgesia, Gefapixant is given by intraplantar or oral administration to the rats, with different concentrations (6, 20, and 60 mg/kg) two times a day and continues up to a week[2].

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

Molecular Weight









Please store the product under the recommended conditions in the Certificate of Analysis.


Room temperature in continental US; may vary elsewhere

  • Molarity Calculator

  • Dilution Calculator

The molarity calculator equation

Mass (g) = Concentration (mol/L) × Volume (L) × Molecular Weight (g/mol)

Mass   Concentration   Volume   Molecular Weight *
= × ×

The dilution calculator equation

Concentration (start) × Volume (start) = Concentration (final) × Volume (final)

This equation is commonly abbreviated as: C1V1 = C2V2

Concentration (start) × Volume (start) = Concentration (final) × Volume (final)
× = ×
C1   V1   C2   V2

Inquiry Online

Your information is safe with us. * Required Fields.

Product name



Applicant name *


Email address *

Phone number *


Organization name *

Country or Region *


Requested quantity *


Bulk Inquiry

Inquiry Information

Product Name:
Cat. No.:


Cat. No.: HY-101588