Safety profiles and efficacy of infliximab therapy in Japanese patients with plaque psoriasis with or without psoriatic arthritis, pustular psoriasis or psoriatic erythroderma: Results from the prospective post-marketing surveillance.

A large-scale prospective post-marketing surveillance was conducted to evaluate the safety and efficacy of infliximab in Japanese patients with plaque psoriasis, psoriatic arthritis, pustular psoriasis and psoriatic erythroderma. This study was conducted in all psoriasis patients treated with infliximab after its Japanese regulatory approval. Infliximab was administrated at 5 mg/kg at weeks 0, 2 and 6, and every 8 weeks thereafter. Patients were serially enrolled and observed for 6 months to evaluate the safety and efficacy. The safety and efficacy were evaluated in 764 and 746 patients, respectively. Incidences of any and serious adverse drug reactions were 22.51% and 6.94%, respectively, and those of any and serious infusion reactions were 6.15% and 1.31%, respectively, which were comparable with the results in the post-marketing surveillance with 5000 rheumatoid arthritis patients in Japan. Major adverse drug reactions during the follow-up period were infections (5.10%) including pneumonia, cellulitis and herpes zoster, however, no tuberculosis was observed. The safety profiles were equivalent, regardless of the psoriasis types. No new safety problems were identified. The response rates on global improvement and median improvement rate of Psoriasis Area and Severity Index in all patients were 88.0% and 85.0%, respectively. Of note, the efficacy was equivalent for each psoriasis type as well as for each body region. Infliximab was also effective in pustular psoriasis symptoms, joint symptoms and nail psoriasis, as well as improvement of quality of life. Infliximab was confirmed to be highly effective and well tolerated in treating refractory psoriasis, including pustular psoriasis and psoriatic erythroderma.