The efficacy of biologics for psoriasis, particularly tumor necrosis factor-α (TNF-α) inhibitors, is lower in patients with late-onset small and gigantic plaques vs patients with large plaques and early onset psoriasis, study results published in the Journal of Dermatology suggest.
Clinical record data of treatment-naïve patients with psoriasis vulgaris who had started therapy with either infliximab, adalimumab, or ustekinumab between 2010 and 2015 were retrospectively reviewed. Patients were classified into a small plaque subtype (n=53), large plaque subtype (n=26), or gigantic plaque subtype (n=8) based on size of plaques on the back.
In addition, patients were further classified as having early-onset psoriasis (EOP) (onset <40 years) or late-onset psoriasis (LOP) (≥40 years). A time to event survival analysis was used to evaluate the efficacy of biologic agents and the differences in efficacy between plaque subtypes.
Biologic agents were associated with significantly better efficacy in large plaques vs small or gigantic plaques (P =.0007). Survival curves indicated that TNF-α also had significantly better efficacy in large plaques compared with small and gigantic plaques (P =.0122). Slightly better survival of TNF-α inhibitors was observed in EOP vs LOP (P =.1389).
In a categorical analysis, infliximab survived in 16 patients compared with termination in 9 patients, adalimumab survived in 25 patients and was terminated in 11 patients, and ustekinumab survived in 23 patients and was terminated in 3 patients (Chi-square test; P =.0137). Overall, biologic agents survived in 37 patients and were terminated in 16 patients in the small plaque category, 26 patients survived and 0 patients terminated biologics in the large plaque group, and 3 patients survived and 5 patients terminated biologic agents in the gigantic plaque group (Chi-square test; P =.0004).
Study limitations include its retrospective and observational nature, as well as the recruitment of clinical data from patients enrolled at a single center.
The researchers wrote that they hope their “pilot study can help to optimize the treatment of patients with various forms of plaque psoriasis.”
Ito K, Bayaraa B, Imafuku S. Relationship between the efficacy of biologics and clinical plaque psoriasis subtypes in Japanese patients: A single-center pilot study [published online September 25, 2019]. J Dermatol. doi:10.1111/1346-8138.15089