- Guide to PHARMACOLOGY
Synonyms: AF-219 | AF219 | Lyfnua® | MK7264 | MK‐7264
gefapixant is an approved drug (Japan (2022))
Compound class: Synthetic organic
Comment: Gefapixant (MK‐7264, and formerly AF-219) is a P2X3 and P2X2/3 receptor antagonist. Experimental results have shown that gefapixant acts as a reversible allosteric antagonist, that exhibits preferential activity at closed channels.
Studies in rodent models have provided evidence that supports investigation of gefapixant as a novel treatment for chronic sensitisation conditions .
Ligand Activity Visualisation Charts
These are box plot that provide a unique visualisation, summarising all the activity data for a ligand taken from ChEMBL and GtoPdb across multiple targets and species. Click on a plot to see the median, interquartile range, low and high data points. A value of zero indicates that no data are available. A separate chart is created for each target, and where possible the algorithm tries to merge ChEMBL and GtoPdb targets by matching them on name and UniProt accession, for each available species. However, please note that inconsistency in naming of targets may lead to data for the same target being reported across multiple charts.✖
|No information available.|
|Summary of Clinical Use|
|Gefapixant is being evaluated in clinical trials for indications that are underscored by chronic sensitisation. The most advanced trials are ongoing in patients with chronic refractory/idiopathic cough. A trial in patients with virally-induced acute cough (NCT03569033) was terminated as it was unlikely to meet its study endpoints upon assessment of interim efficacy data. Click here to link to ClinicalTrials.gov's full list of gefapixant trials.
The following references highlight the clinical potential of ATP antagonism in human diseases: [2,6]. First approval was granted in Japan in 2022, for the treatment of refractory or unexplained chronic cough .
|Clinical Trial ID||Title||Type||Source||Comment||References|
|NCT01432730||A Study to Assess the Efficacy of Gefapixant (MK-7264/AF-219), in Participants With Chronic Cough (MK-7264-006)||Phase 2 Interventional||Afferent Pharmaceuticals, Inc.||Gefapixant (AF-219) reduces the P2X3 receptor-induced hypersensitisation of airway sensory neurons that can underly chronic cough, and exhibits antitussive efficacy in human trial subjects with refractory chronic cough.||1|
|NCT02349425||A Dose Escalation Study of Gefapixant (AF-219/MK-7264) in Refractory Chronic Cough||Phase 2 Interventional||Afferent Pharmaceuticals, Inc.||This dose escalation study showed that gefapixant's antitussive efficacy was maintained at lower doses than has been determined previously, and that the lower effective dose improved tolerability.||8|
|NCT03449147||A Study of Gefapixant (MK-7264) in Adult Participants With Chronic Cough (MK-7264-030)||Phase 3 Interventional||Merck Sharp & Dohme Corp.||The COUGH-2 phase 3 study||5|
|NCT03449134||A Study of Gefapixant (MK-7264) in Adult Participants With Chronic Cough (MK-7264-027)||Phase 3 Interventional||Merck Sharp & Dohme LLC||The COUGH-1 phase 3 study||5|