Long-Term Efficacy and Safety of Secukinumab in Children and Adolescents with Moderate-to-Severe Chronic Plaque Psoriasis: Four-Year Results of a Randomized, Phase III, Open-Label Trial.

Background: The efficacy and safety of secukinumab up to week 52 in children and adolescents with moderate-to-severe chronic plaque psoriasis have been demonstrated previously (NCT03668613). Herein, we report the long-term efficacy, safety, and tolerability of secukinumab over a period of up to 208 weeks.

Methods: In this randomized open-label trial, patients (6 to < 18 years) were randomized 1:1 to receive low-dose (LD; N = 42) or high-dose (HD; N = 42) secukinumab stratified by weight (< 25 kg, 25 to < 50 kg, or ≥ 50 kg) and disease severity (moderate or severe). Patients weighing < 25 kg received 75 mg secukinumab (both LD and HD); 25 to < 50 kg received 75 mg (LD) or 150 mg (HD) secukinumab; and ≥ 50 kg received 150 mg (LD) or 300 mg (HD) secukinumab. The study assessed Psoriasis Area and Severity Index (PASI) 75/90/100 response, Investigator's Global Assessment modified 2011 (IGA mod 2011) 0/1 response, Children's Dermatology Life Quality (CDLQI) 0/1 response, and safety. The impact of secukinumab treatment on physical development was also assessed.

Results: Overall, 79.8% (67 of 84) enrolled patients completed 4 years of treatment (secukinumab LD [N = 31] and secukinumab HD [N = 36]). Both treatment groups showed sustained PASI and IGA mod 0/1 responses throughout the treatment period (at week 208, PASI 75/90/100 [secukinumab LD: 96.3%/88.9%/51.9%; secukinumab HD: 87.9%/81.8%/72.7%] and IGA mod 2011 0/1 [secukinumab LD: 85.2%; secukinumab HD: 84.8%]). Mean PASI score remained low in both treatment groups, from week 12 through week 208; at week 208, mean percentage change in PASI scores from baseline was - 95.7% (mean absolute score: 18.46 [baseline]; 0.76 [week 208]) with secukinumab LD and - 94.5% (mean absolute score: 19.25 [baseline]; 1.07 [week 208]) with secukinumab HD. CDLQI 0/1 response remained high in both treatment groups from week 12 through week 208 (secukinumab LD: 75.0%; secukinumab HD: 88.2%). Safety profile of secukinumab with long-term (~313.9 patient-years) treatment was favorable and in line with the known safety profile reported previously for 52-week treatment. No dose-dependent safety observations were noted. There were no deaths recorded throughout the entire duration of the treatment. Nonfatal serious adverse events (SAEs) were reported in four (9.5%) patients in the LD group (coronavirus disease 2019 [COVID-19], Crohn's disease, infectious mononucleosis, intentional self-injury, tibia fracture) and two (4.8%) patients in the HD group (appendicitis, tonsillitis). The incidence of treatment-emergent adverse events was similar in both secukinumab dose groups (LD [78.6%] and HD [83.3%]). No impact on the growth and development, or sexual maturation of pediatric patients, was noted with long-term treatment.

Conclusions: Secukinumab demonstrated sustained long-term efficacy and improved quality of life through week 208 in pediatric patients with moderate-to-severe chronic plaque psoriasis. The treatment was well tolerated, and safety data were consistent with the known favorable safety profile of secukinumab.

Clinical trial registration no: NCT03668613.