Background: Treatment with the tumor necrosis factor-alpha antibody adalimumab for 12–16 weeks produces a satisfactory response [i.e., 75% reduction in psoriasis area and severity index (PASI)] in a majority (70–80%) of patients with psoriasis. We asked whether 311 nm ultraviolet B (UVB) can improve therapeutic response of psoriatic lesions to adalimumab.
Methods: Four patients (age range, 49–67 years) with moderate to severe plaque-type psoriasis were treated with standard dosage of adalimumab. During adalimumab therapy, a randomly selected body half (left or right, excluding the head) was irradiated with 311 nm UVB three times weekly for 6 weeks. Treatment response was monitored weekly in terms of half-body PASI.
Results: 311 nm UVB significantly accelerated the therapeutic response during adalimumab treatment. At the start of 311 nm UVB therapy, the mean PASI was 14.8. After 6 weeks of 311 nm UVB therapy, the mean PASI was 2.0 on UV-irradiated body halves and 6.9 on non-irradiated body halves (difference, 4.9; 95% confidence interval, 0.4–9.4; P=0.041; 2-tailed paired t-test). This corresponded to an overall mean PASI reduction from baseline (i.e., adalimumab start) of 86% on UV-irradiated body halves vs. 53% on non-irradiated body halves.
Conclusion: 311 nm UVB may accelerate and improve the clearance of psoriatic lesions in adalimumab-treated patients.