For a study, obesity was prevalent comorbidity of psoriasis, and it could reduce the effectiveness of biological therapy. In patients with greater body weight, compare the effectiveness, safety, and tolerability of secukinumab 300 mg every 2 weeks (Q2W) vs secukinumab 300 mg every 4 weeks (Q4W). Furthermore, 331 patients with moderate-to-severe chronic plaque psoriasis weighing less than or equal to 90 kg were randomly assigned to receive secukinumab 300 mg Q2W or secukinumab 300 mg Q4W in the multicenter, double-blind, parallel-group experiment. Patients on the Q4W regimen who did not attain PASI90 at Week 16 were re-assigned to either stay on the Q4W regimen or up-titrate to Q2W. At Week 16, Q2W dosing (N=165) resulted in significantly greater PASI90 answers compared with Q4W (N=166; 73.2% vs 55.5%, one-sided P=0.0003, odds ratio estimate (95% CI): 2.3). (1.4, 3.8). At Week 52, the Q2W arm (N=165) had greater efficacy responses than the Q4W arm (N=83); PASI75: 88.9% vs 74.8%; PASI90: 76.4% vs 52.4%; PASI100: 46.7% vs 27.3% IGA 0/1: 75.9% vs 55.6%; and DLQI 0/1: 66.1% vs 48.8%. PASI90 non-responders who up-titrated to Q2W (N=31) had higher efficacy responses at Week 32 (16 weeks post-up-titration, PASI90: 38.7% vs 16.5%) than those who stayed on Q4W (N=40). The safety results were comparable across treatment arms and were consistent with the secukinumab safety profile established. In moderate-to-severe plaque psoriasis patients weighing less than or equal to 90 kg, secukinumab 300 mg Q2W showed greater and maintained effectiveness than Q4W. Up-titration to a Q2W regimen provided further benefits to PASI90 non-responders (NCT03504852).