Roughly half of psoriasis patients on adalimumab showed complete resolution in specific body regions after 16 weeks, according to an analysis of the phase III CHAMPION trial reported in the May issue of the Journal of Drugs in Dermatology.
Breaking down the Psoriasis Area Severity Index (PASI) scores by body regions allows for a more clinically relevant assessment of the outcomes, said Dr. Alexander A. Navarini of King’s College, London, and his colleagues.
Adalimumab patients averaged significant improvements in PASI scores from baseline for each body region, compared with scores with methotrexate and placebo. The average improvements for the head were 81%, 57%, and 27% for the adalimumab, methotrexate, and placebo groups, respectively. Improvements for the trunk were 86%, 51%, and 20%, respectively; improvements for the upper extremities were 79%, 53%, and 15%; and improvements for the lower extremities were 78%, 53%, and 15%.
Overall, 50% of adalimumab patients achieved a PASI 100 for the head and trunk regions, compared with 23% of methotrexate patients and 17% of placebo patients (J. Drugs Dermatol. 2014;13:554-62).
The complexity of calculating a PASI score makes it difficult to interpret, said Dr. Navarini and his colleagues.
"The score has difficulty expressing a significant reduction of erythema, scaling, and infiltration of the lesions when no modification of the affected area is observed," they wrote. "Body area is the last parameter to be affected by treatment." In a post-hoc analysis of the CHAMPION study, which showed the safety and effectiveness of adalimumab, compared with methotrexate and placebo, the researchers calculated PASI scores by body regions and by PASI components (J. Drugs Dermatol. 2014;13:554-62).
The study included adults aged 18 years and older with stable, moderate to severe chronic plaque psoriasis. A total of 108 patients were randomized to adalimumab, 110 to methotrexate, and 53 to placebo.
The researchers also reviewed data based on PASI component scores for erythema, induration, desquamation, and surface area.
"For all PASI components, the mean percent improvement in PASI score was significantly greater (P less than .05) for adalimumab-treated patients, compared with methotrexate and placebo-treated patients, at all time points, with the exception of week 1," the researchers wrote.
In addition, improvements in disease quality of life scores correlated with improvements in PASI body region scores and PASI component scores.
The analysis of PASI body region scores and PASI component scores has not been published for other treatments, the researchers noted. However, this strategy "allows for a more thorough evaluation and tracking of a patient’s disease severity as well as response to treatment, no matter how extensive or localized the disease manifestations may be," they added.