Treatment with infliximab is associated with favorable initial efficacy in patients with psoriasis, but drug survival rapidly declines after 2 years of therapy, according to study data published in Dermatologic Therapy. Lower levels of cholesterol and lymphocyte percentage may be predictive of longer continuation of infliximab treatment in these patients.
Clinical records of 42 patients with psoriasis who were treated with ≥1 dose of infliximab at a hospital in China from January 2015 to April 2020 were retrospectively reviewed. The infliximab dose was set at 5 mg/kg at weeks 0, 2, and 6 for the induction period, followed by 8 mg/kg every week thereafter during the maintenance period. Drug survival, defined as the time (in months) from the start of treatment to discontinuation, was assessed.
Overall, 30 patients in this study were biologic-naïve, whereas 6 patients had previously received etanercept. A total of 16 patients (38.1%) in the cohort had psoriatic arthritis. At presentation, the mean age of the study population was 38.7±14.6 years, and the mean age at the onset of psoriasis was 29.3±13.4 years. The majority of patients (83.3%) had early onset psoriasis.
The mean baseline PASI score was 16.3±8.6. During the first 16 weeks of treatment, the PASI score rapidly decreased. The score was generally maintained until 24 weeks, after which it increased at week 52 following treatment discontinuation. A 75% reduction in the PASI score (PASI75) was achieved in 69.04% of patients at 16 weeks, 71.4% of patients at 24 weeks, and 55.6% of patients at 52 weeks. During the second year of treatment, there was a rapid decrease in the percentage of patients with improvements in the PASI75 and PASI90 scores.
Discontinuation of therapy occurred in 57.1% (n=24) of patients, mostly due to lack of treatment efficacy (70.8%). The median drug survival duration was 69 weeks. The drug survival rates were 62.58%, 32.33%, and 12.94% in the first year, second year, and at 138 weeks, respectively. For the drug survival outcome, the researchers found no difference between patients with psoriatic arthritis and psoriasis vulgaris without arthritis (P =.5993) or between men and women (P =.2851).
In a multivariate Cox analysis, variables associated with drug survival included lower cholesterol level (hazard ratio [HR], 3.482; 95% CI, 1.536-7.893; P =.003) and lymphocyte percentage (HR, 1.076; 95% CI, 1.018-1.138; P =.010).
Limitations of this study included its relatively small sample size as well as the lack of investigation into additional variables which may have influenced treatment outcome (ie, body mass index and generation of anti-drug antibodies).
The researchers added that although “high cholesterol level and lymphocyte percentage might function as negative predictor for infliximab persistence,” further study is needed.
Chen W, Ding Y, Lu J, Shi Y, Goa Y, Peng C. Efficacy and survival of infliximab in psoriasis patients: A single-center experience in China. Dermatol Ther. Published online August 26, 2020. doi:10.1111/dth.14227