RMC-6236 is a non-covalent pan-RAS(ON) inhibitor from Revolution Medicines, which shows remarkable efficacy in tumors driven by RAS mutants that were previously considered “undruggable,” such as G12V/D/A/S, G13X, and Q61X. RMC-6236 exerts its action via a “tri-complex” mechanism, gluing RAS to the ubiquitously expressed chaperone protein, cyclophilin A. Our in-depth article covers the presentation given at the AACR 2024 meeting, which outlines the discovery and preclinical profile of RMC-6236 as well as the latest clinical updates.

Zuranolone (ZURZUVAE™) is an oral positive allosteric modulator of CNS GABA signaling developed by Sage Therapeutics, in collaboration with Biogen, which was approved in August 2023 by the FDA for the treatment of postpartum depression (PPD). In 2019 Sage had received approval for brexanolone (ZULRESSO™), an IV formulation of the endogenous GABA PAM neurosteroid hormone for PPD, but an oral drug is expected to greatly increase access to treatment. Zuranolone was also investigated for major depressive disorder, although the FDA declined to extend approval for this indication.

Cerevance’s CVN293 is an oral, CNS-penetrant, selective inhibitor of potassium efflux-mediated NLRP3-inflammasome activation in microglia for the treatment of neurodegenerative disorders. Cerevance’s NETSseq platform was used to discover a microglia-specific potassium efflux channel, KCNK13, which allows modulation of the NLRP3-inflammasome in the CNS without affecting peripheral innate immunity. Read the full article to discover highlights on the CNS-penetration of highly polar compounds and how particle size can be key to oral bioavailability

The Takeda GPR139 agonist, TAK-041 , is a CNS-penetrant GPCR agonist being explored for schizophrenia symptoms and is an interesting example of a triazinone-containing clinical candidate. GPR139 is an orphan GPCR that’s highly expressed in the human habenula, which plays a major role in avoidance behavior. Lesions in the habenula cause [...]

AZD4747 is a CNS-penetrant, oral KRAS G12C covalent inhibitor for the treatment of CNS-metastatic KRAS-mutant cancers. KRAS inhibitors have tended to be quite large and fall outside the range of physicochemical properties generally required for CNS permeability. (MW < 360 Da, cLogD < 2, TPSA < 90 Å2. AZD4747 is much smaller than marketed KRAS G12C inhibitors but maintains exceptional cellular potency. The team also encountered an unexpected toxicity that scientists working on covalents should pay attention to.