Discovery of a Novel Small-Molecule Interleukin-6 Inhibitor through Virtual Screening Using Artificial Intelligence.

Background Interleukin-6 (IL-6) is a multifunctional cytokine involved in various cell functions and diseases. Thus far, several IL-6 inhibitors, such as, humanized monoclonal antibody have been used to block excessive IL-6 signaling causing autoimmune and inflammatory diseases. However, anti-IL-6 and anti-IL-6 receptor monoclonal antibodies have some clinical disadvantages, such as a high cost, unfavorable injection route, and tendency to mask infectious diseases. While a small-molecule IL-6 inhibitor would help mitigate these issues, none are currently available. Objective The present study evaluated the biological activities of identified compounds on IL-6 stimulus. Methods We virtually screened potential IL-6 binders from a compound library using INTerprotein's Engine for New Drug Design (INTENDD®) followed by the identification of more potent IL-6 binders with artificial intelligence (AI)-guided INTENDD®. The biological activities of the identified compounds were assessed with the IL-6-dependent cell line 7TD1. Results The compounds showed the suppression of IL-6-dependent cell growth in a dose-dependent manner. Furthermore, the identified compound inhibited expression of IL-6-induced phosphorylation of signal transducer and activator of transcription 3 in a dose-dependent manner. Conclusion Our screening compound demonstrated an inhibitory effect on IL-6 stimulus. These findings may serve as a basis for the further development of small-molecule IL-6 inhibitors.