CD40 Agonist Therapy in Melanoma: Translating Preclinical Promise Into Clinical Practice

Melanoma is an aggressive skin cancer that, once metastatic, accounts for a disproportionate share of skin-cancer mortality. Contemporary management includes surgical excision with sentinel-node assessment, adjuvant or neoadjuvant systemic therapy, radiotherapy in selected settings, targeted inhibition for BRAF/MEK-mutant disease, and intralesional modalities; nevertheless, many patients require effective systemic options. Immunotherapy has transformed outcomes by restoring antitumor T-cell activity. Within this paradigm, activation of CD40, a pivotal costimulatory receptor on antigen-presenting cells (APCs), has emerged as a means to reprogram tumor immunity in melanoma. Available agents span several classes, including agonist monoclonal antibodies, CD40L-based fusion proteins, and engineered bispecific or conditionally activatable formats. A principal mechanism is dendritic-cell licensing that enhances cross-priming of melanoma-specific CD8⁺ T cells. This review summarizes the latest evidence on CD40 agonist therapy in melanoma, moving from biological rationale to translational data. We summarize mechanistic underpinnings, delineate therapeutic classes and leading agents, and critically appraise findings from preclinical models and early-phase clinical studies, including signals of activity and salient safety considerations. Finally, we outline future perspectives for integrating CD40 agonists with established standards of care and for prioritizing biomarker-guided development to translate preclinical promise into durable clinical benefit.