What is the mechanism of action of Mobosetinib/Mobosetinib Capsules?

Mobocertinib/Mobocertinib is an oral TKI that selectively targets EGFR and HER2 exon 20 insertion mutations. Although the role of HER2 exon 20 insertion mutations in non-small cell lung cancer is unclear, their presence accounts for an important portion of HER2 mutations in NSCLC (90%). Mobosetinib will likely focus on EGFR mutations.

The affinity of mobosetinib toEGFRex20ins mutation is achieved through a series of interactions at the EGFR binding site. This involves forming an irreversible covalent bond with cysteine u200bu200b797 residue in EGFR. In addition, the C5-carboxylic isopropyl ester moiety on the middle pyrimidine ring of mobosertinib interacts with the C790 gatekeeper residue in the ATP-binding pocket of EGFR, thereby selectively targeting EGFRex20ins oncogenic variants.

The results of the affinity of mobosetinib for EGFR x20ins predicted significant inhibitory effects on various mutants, with IC50 values 1.5 to 8 times lower than WT (IC50s were 4.3 to 22.5nM and 34.5nM, respectively) . 5 In preclinical studies, all genes containing common activating mutations (with or withoutT790M resistance mutations D, L, DT and lt), all uncommon activating mutations (G719A, G719S, S768I, L 8611) was found to be more effective at inhibiting mutant EGFR than WT EGFR. Due to its high selectivity, mobosetinib is hypothesized to reduce the risk of dose-limiting toxicities compared with other drugs that are less selective for mutant EGFR.

The activity of mobosetinib was evaluated in CUTO14 and LU0837, patient-derived lung adenocarcinoma cell lines harboring epidermal growth factorx20ins ASV mutations and NPH mutations, respectively. The analysis showed that at similar concentrations of 100 nm/L and 1000 nmol/L, mobosetinib inhibited phosphorylation in CUTO14 cells and therefore inhibited EGFR signaling more effectively than osimertinib (80% and 100% vs. 38% and 63%, respectively). In addition, with osimertinib (osimertinib), erlotinib (erlotinib), gefitinib (gefitinib) Compared with afatinib (afatinib) , moboxetinib greatly reduced the viability of CUTO14 cells. In addition, mobosetinib was found to be more effective than erlotinib, gefitinib, and ositinib in inhibiting LU0387 cell viability.

References:https://www.dovepress.com/clinical-utility-of-mobocertinib-in-the-treatment-of-nsclc--patient-se-peer-reviewed-fulltext-article-OTT