FLT3 and rheumatoid arthritis: Among these, medications targeting ERBB2 (Fostamatinib), IL6R (Levilimab, Sarilumab, Tocilizumab, Vobarilizumab), CD28 (TGN-1412), CD40 (Iscalimab, BI-655064), and FLT3 (Pexidartinib) have been approved or are in clinical trials for RA treatment.