Notably, combination therapy with SOS1 inhibitor MRTX0902, Trametinib, and anti-PD-1 antibody effectively increased intratumoural CD8+ T cell infiltration and improved survival. Our study thus reveals that targeting wild-type KRAS signalling in combination with ICIs may serve as an effective treatment strategy for advanced HCC patients.

P1/2, N=228, Active, not recruiting, Mirati Therapeutics Inc. | Recruiting --> Active, not recruiting

P1, N=104, Recruiting, Bayer | Trial completion date: Nov 2027 --> Mar 2028 | Trial primary completion date: Jan 2027 --> Jul 2027

Among these, A15f and B5a emerged as the most potent compounds comparable to BI-3406...Molecular docking revealed that these two compounds shared a conserved binding mode with SOS1, similar to the reported inhibitors. These findings provide foundation for further development of SOS1-targeted anticancer therapeutics and offer valuable insights for structural optimization of this novel class of inhibitors.

P1, N=71, Active, not recruiting, Boehringer Ingelheim | Trial completion date: Apr 2025 --> Dec 2025 | Trial primary completion date: Apr 2025 --> Dec 2025

Furthermore, markedly stronger, synergistic antitumor effects were observed upon concomitant treatment with BI-3406 and MRTX1133 in the same in vivo LUAD mouse model. Our data confirm SOS1 as an actionable therapy target in RAS-dependent cancers and suggest that BI-3406 treatment may yield clinical benefit both as monotherapy or as a potential combination partner for multiple RAS-targeting strategies.

Besides BAY-293, BH1406 cells proved to be sensitive to the SOS1 inhibitors MRTX0902 and BI-3406...Additionally, the PI3K inhibitor dactolisib, the GSK-3 inhibitor BI-5521 as well as the bromodomain protein-directed PROTAC ARV-771 inhibited the growth of BH1406 cells significantly and showed synergistic interaction with BAY-293...BH1406 cells represent a novel cellular model suitable for the molecular characterization of SOS1 druggability. Such rare oncogenic driver genes are not included in standard NGS panels and need to be detected by expanded assays like WES.

Furthermore, molecular dynamic simulations have unveiled that the tricyclic quinazoline derivatives exhibit extensive interaction with Tyr884, a crucial residue for the recognition between SOS1 and KRAS. Our findings provide fresh insights into the design of future SOS1 inhibitors, paving the way for innovative therapeutic strategies.

P1, N=104, Recruiting, Bayer | Not yet recruiting --> Recruiting

P1, N=104, Not yet recruiting, Bayer

Here, we identified targeting proximal receptor tyrosine kinase (RTK) signaling using the SOS1 inhibitor (SOS1i) BI-3406 as a strategy to improve responses to G12Ci treatment...Treatment with SOS1i both delayed acquired G12Ci resistance and limited the total number of resistant colonies regardless of KEAP1 and STK11 mutational status. Together, these data suggest that targeting SOS1 could be an effective strategy to both enhance G12Ci efficacy and prevent G12Ci resistance regardless of co-mutations.

In this study, we developed a potent SOS1 PROTAC SIAIS562055, which was designed by connecting a CRBN ligand to an analogue of the SOS1 inhibitor BI-3406...SIAIS562055 and BCR-ABL inhibitors synergistically enhanced inhibition of ABL phosphorylation and downstream signaling, demonstrating robust antitumor activities in both mouse xenografts and primary CML patient samples. In summary, this study suggests that PROTAC-mediated SOS1 degradation represents an effective therapeutic strategy for treating not only KRAS-mutant cancers but also BCR-ABL-harboring leukemia.