[en] The radial density and temperature profiles of ignited plasmas utilizing non-DT fuels can be optimized to maximize fusion power density and minimize required anti n tau/sub E/ under the constraint of a maximum average plasma pressure. Strong axial temperature peaking or strong density peaking is advantageous, according to whether the fusion reactivity increases faster or more slowly than quadratically with temperature, respectively. For tokamak plasmas with maximum beta limited to 10% or less by MHD instability, optimal profile tailoring allows ignition of catalyzed D-D or D-³He fuels in devices of reasonable size (R₀ approximately < 8 m), and with first-wall power loadings exceeding 1 MW/m²