Before treatment, participants underwent routine blood and urine tests, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), liver and kidney function tests, tuberculous infection of T cells spot tests, hepatitis B virus marker tests, chest CT scans, etc. After exclusion of relevant contraindications, participants received subcutaneous ustekinumab therapy. During the treatment period, participants received ustekinumab at weeks 0, 4, 16, and every 12 weeks thereafter until week 48. The single dose of ustekinumab was 45 mg for adult subjects weighing ≤ 100 kg, and 90 mg for subjects weighing > 100 kg. The ustekinumab dosage for pediatric participants was 0.75 mg/kg for participants weighing < 60 kg; 45 mg for pediatric participants weighing 60 kg to 100 kg; and 90 mg for pediatric participants weighing > 100 kg.

Before treatment, participants underwent routine blood and urine tests, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), liver and kidney function tests, tuberculous infection of T cells spot tests, hepatitis B virus marker tests, chest CT scans, etc. After exclusion of relevant contraindications, participants received subcutaneous secukinumab therapy. During the treatment period, participants received secukinumab at weeks 0, 1, 2, 3, and 4, and every 4 weeks thereafter until week 48. The secukinumab dosage was 300mg for adult humans. Pediatric participants received a dose based on their weight category (< 50 kg, ≥ 50 kg): participants weighing < 50 kg received 75 mg, those weighing ≥ 50 kg received 150 mg.

During the treatment period, participants received either ustekinumab at weeks 0, 4, 16, and every 12 weeks thereafter until week 48, or secukinumab at weeks 0, 1, 2, 3, and 4, and every 4 weeks thereafter until week 48. The dose of ustekinumab/secukinumab was referenced to the dose used for moderate to severe plaque psoriasis. The single dose of ustekinumab was 45 mg for adult subjects weighing ≤ 100 kg, and 90 mg for subjects weighing > 100 kg. The ustekinumab dosage for pediatric participants was 0.75 mg/kg for participants weighing < 60 kg; 45 mg for pediatric participants weighing 60 kg to 100 kg; and 90 mg for pediatric participants weighing > 100 kg. The secukinumab dosage was 300mg for adult humans. Pediatric participants received a dose based on their weight category ( <50 kg, ≥50 kg): participants weighing < 50 kg received 75 mg, those weighing ≥ 50 kg received 150 mg.

Efficacy analyses were performed based on the scores of Generalized Pustular Psoriasis Area and Severity Index (GPPASI) at week 0, 2, 4, 12, 24, and 48. GPPASI provided a numeric scoring system to assess patient's overall disease state of GPP, ranging from 0 to 72, with higher scores indicating more severe conditions. Clinical efficacy was evaluated by GPPASI -50, -75, -90, and -100 responses at each time point.

Efficacy analyses were performed based on the scores of Generalized Pustular Psoriasis Physician Global Assessment (GPPGA) at week 0, 2, 4, 12, 24, and 48. The investigator scored the erythema, pustules, and scale of all GPP lesions from 0 to 4 using GPPGA. Each component was graded separately, and the average was calculated. The final GPPGA was determined by this composite score.