A humanized immunoglobulin (Ig) G1, Fc-silenced, bispecific, agonistic monoclonal antibody targeting both CD40 and 4-1BB (CD137; tumor necrosis factor receptor superfamily member 9; TNFRSF9), with potential immunostimulatory and antineoplastic activity. Upon administration, anti-CD40/anti-4-1BB bispecific agonist monoclonal antibody GEN1042 simultaneously binds to CD40 and 4-1BB, crosslinks CD40 and 4-1BB positive cells, induces conditional stimulation, and activates both CD40- and 4-1BB-medicated signaling. The activation of CD40-mediated signaling triggers the proliferation and activation of antigen-presenting cells (APCs) and activates T-cells. This results in an enhanced cytotoxic T-lymphocyte (CTL)-mediated immune response against tumor cells. The activation of 4-1BB-mediated signaling induces cytokine production and promotes T-cell mediated anti-tumor immune responses. CD40, a cell surface receptor and member of the tumor necrosis factor receptor superfamily (TNFRSF), is expressed on various immune cells, such as dendritic cells (DCs), macrophages and B-cells, and plays a key role in the activation of the immune system. 4-1BB, a surface glycoprotein of the TNFRSF, is an inducible costimulatory receptor that plays a key role in T-cell proliferation, survival and cytolytic activity.