TLR7 and IFNα stimulation of B cells promotes IgM+ response and expansion of autoreactive B cells35 and overactivity of both the TLR7 and IFNα system are established features of SLE.36–38 In our experiments, iberdomide significantly inhibited the production of IgG and IgM from B cells induced by resiquimod alone or resiquimod +IFNα (figure 1B), an effect that was shown to be dose-dependent, with both 10 and 100 nM inducing a significant reduction of Ig production compared with vehicle (figure 1C). Here, IFNA1 is linked to systemic lupus erythematosus.