Fusion Peptide
A synthetic molecule combining two or more peptide sequences to create a single compound with multiple biological activities or enhanced properties. Fusion peptide strategies can combine targeting and therapeutic functions, such as a receptor-binding peptide linked to a cell-killing payload.
Technical Context
Fusion protein/peptide design strategies: Fc fusion (therapeutic peptide fused to the Fc region of IgG antibody — provides half-life extension through FcRn-mediated recycling; dulaglutide = GLP-1 analogue-Fc fusion, romiplostim = thrombopoietin-binding peptide-Fc fusion), albumin fusion (peptide fused to human serum albumin — extending half-life to albumin's ~19-day half-life), CTP fusion (C-terminal peptide of hCG fused to therapeutic protein — somatrogon uses CTP technology for long-acting GH), and targeting fusion (combining a targeting peptide with a therapeutic payload). The linker between fusion partners is critical — it must be long enough to allow independent folding and function of both domains while being stable enough to resist proteolytic cleavage. Rigid vs flexible linker design affects the spatial relationship between fusion partners.