The arachidonic acid (AA) metabolite, 20-hydroxy-5,8,11,14-eicosatetranoic acid (20-HETE), has been extensively studied as a modulator of kidney function and a mediator of kidney diseases over decades. The receptor for 20-HETE, the G-coupled protein receptor GPR75, was only recently identified (2017), and GPR75/20-HETE pathway modulators are of industry interest in many disease areas including obesity (e.g. 2020 Regeneron patent filing) and kidney diseases (e.g. 2018 Taisho patent filing).

“Compound 19” (iron-binder) is an oral inhibitor of the hypoxia-inducible factor (HIF) propyl hydroxylase domain (HIF-PHD), increasing HIF levels to activate EPO transcription and promote hematopoiesis for treatment of anemia. Interestingly, this compound is modeled to make a bi-dentate interaction with an iron co-factor of HIF-PHD via a [...]

Inaxaplin (VX-147), developed by Vertex, is an inhibitor of APOL1 channel activity currently in a Ph. II/III pivotal study for the treatment of chronic kidney disease caused by specific variants of the APOL1 gene. It was recently granted Breakthrough Therapy designation by the FDA and PRIME designation by the EMA. The discovery story, which is an excellent case study for the use of MetID. Inaxaplin has been called “the most important genomic-driven drug discovery for chronic kidney disease this century”, acting on a target with a fascinating human genetic validation story.

Daprodustat is the first HIF-prolyl hydroxylase domain (PHD) inhibitor that has been approved for the treatment of anemia in chronic kidney disease (CKD) and marks the first novel anemia treatment approved in the US in >30 years. PHDs have been attractive targets for treating anemia, especially in CKD patients, because the enzymes regulate levels of hypoxia-inducible factors (HIFs) including HIF-2, which induces the production of erythropoietin that in turn stimulates red blood cell production. The small molecule drug has similar safety and activity as epoetin alfa, an injected biologic.

“Compound 9” is the first potent M3-selective positive allosteric modulator, with potential utility as a biological tool compound. It does have secondary activity against M5 at high doses though. It’s quite a large zwitterion, which is somewhat unusual for GPCRs.