Addressing Atropisomerism in the Development of Sotorasib, a Covalent Inhibitor of KRAS G12C: Structural, Analytical, and Synthetic Considerations.

Nearly a century after its first description, configurationally stable axial chirality remains a rare feature in marketed drugs. In the development of the KRAS inhibitor sotorasib (LUMAKRAS/LUMYKRAS), an axially chiral biaryl moiety proved a critical structural element in engaging a "cryptic" protein binding pocket and enhancing inhibitor potency. Restricted rotation about this axis of chirality gave rise to configurationally stable atropisomers that demonstrated a 10-fold difference in potency.

Modeling receptor flexibility in the structure-based design of KRAS inhibitors.

KRAS has long been referred to as an 'undruggable' target due to its high affinity for its cognate ligands (GDP and GTP) and its lack of readily exploited allosteric binding pockets. Recent progress in the development of covalent inhibitors of KRAS has revealed that occupancy of an allosteric binding site located between the α3-helix and switch-II loop of KRAS-sometimes referred to as the 'switch-II pocket'-holds great potential in the design of direct inhibitors of KRAS. In studying diverse switch-II pocket binders during the development of sotorasib (AMG 510), the first FDA-approved inhibitor of KRAS, we found the dramatic conformational flexibility of the switch-II pocket posing significant challenges toward the structure-based design of inhibitors.

Half-life extension of peptidic APJ agonists by N-terminal lipid conjugation.

Agonism of the endothelial receptor APJ (putative receptor protein related to AT; AT: angiotensin II receptor type 1) has the potential to ameliorate congestive heart failure by increasing cardiac output without inducing hypertrophy. Although the endogenous agonist, pyr-apelin-13 (1), has shown beneficial APJ-mediated inotropic effects in rats and humans, such effects are short-lived given its extremely short half-life. Here, we report the conjugation of 1 to a fatty acid, providing a lipidated peptide (2) with increased stability that retains inotropic activity in an anesthetized rat myocardial infarction (MI) model.

Discovery of a Covalent Inhibitor of KRAS (AMG 510) for the Treatment of Solid Tumors.

KRAS has emerged as a promising target in the treatment of solid tumors. Covalent inhibitors targeting the mutant cysteine-12 residue have been shown to disrupt signaling by this long-"undruggable" target; however clinically viable inhibitors have yet to be identified. Here, we report efforts to exploit a cryptic pocket (H95/Y96/Q99) we identified in KRAS to identify inhibitors suitable for clinical development.

The clinical KRAS(G12C) inhibitor AMG 510 drives anti-tumour immunity.

KRAS is the most frequently mutated oncogene in cancer and encodes a key signalling protein in tumours. The KRAS(G12C) mutant has a cysteine residue that has been exploited to design covalent inhibitors that have promising preclinical activity. Here we optimized a series of inhibitors, using novel binding interactions to markedly enhance their potency and selectivity.