FDA Approves TREMFYA for Pediatric Plaque Psoriasis and Psoriatic Arthritis

In a landmark move, the U.S. Food and Drug Administration has approved TREMFYA® (guselkumab) to treat children aged six years and older (weighing at least 40 kg) with moderate to severe plaque psoriasis and with active psoriatic arthritis. This marks the first time an interleukin‑23 (IL‑23) inhibitor has gained pediatric approval for both conditions.

TREMFYA was already approved for adult moderate to severe plaque psoriasis (in 2017) and adult psoriatic arthritis (in 2020), but this extension into pediatric indications addresses an important treatment gap in younger patients. According to Johnson & Johnson, about 20,000 children under age 10 are diagnosed annually with plaque psoriasis in the U.S., and roughly 14,000 children are affected by psoriatic arthritis. 

The decision was grounded in data from the Phase 3 PROTOSTAR clinical trial, which evaluated TREMFYA in pediatric patients with moderate to severe plaque psoriasis. At Week 16, 56 % of treated children achieved at least 90 % improvement on the Psoriasis Area Severity Index (PASI 90), compared to 16 % on placebo (p < 0.01). In parallel, 66 % of the treatment group attained an Investigator’s Global Assessment (IGA) score of 0/1 versus 16 % in placebo (p < 0.001), with nearly 40 % achieving complete skin clearance (IGA 0) versus 4 % of placebo (p < 0.01). 

For the psoriatic arthritis indication, the FDA relied on pharmacokinetic extrapolation, drawing from adult psoriasis and arthritis studies (VOYAGE 1 & 2, DISCOVER 1 & 2) and the pediatric psoriasis data. These analyses supported the assumption that efficacy and safety in children would align with established adult profiles.

TREMFYA is administered via subcutaneous injection at Week 0, Week 4, then every eight weeks thereafter, with a recommended pediatric dose of 100 mg. Johnson & Johnson describes TREMFYA as a dual‑acting monoclonal antibody: it blocks IL‑23 by binding to its p19 subunit and also binds to CD64 on cells that produce IL‑23 (though the clinical relevance of the CD64 binding remains based on in vitro findings). 

Company and advocacy voices herald the approval as a substantial advance for pediatric care. The National Psoriasis Foundation highlighted the emotional and social burden that skin and joint disease place on children and welcomed any new option offering relief and improved well‑being. Johnson & Johnson emphasized a commitment to monitoring long‑term safety and further investigating TREMFYA’s full potential in both adult and pediatric populations.