Long-term durability and dose escalation patterns in infliximab therapy for psoriasis

Abstract

Infliximab often requires dose escalation to maintain response. Studies regarding long-term durability and dose escalation patterns for psoriasis are few. We sought to evaluate dose escalation patterns in psoriatic patients to identify factors of lack of optimal response to infliximab. A retrospective cohort study included 93 patients (216.3 patient-years) treated with infliximab for psoriasis. Kaplan-Meier analysis assessed drug durability. A median infliximab dose of 5.42 mg/kg/mo (range: 2.71-10.83) for a mean of 28 months was administered. Two thirds of patients received a dose escalation. Concurrent methotrexate extended duration of therapy (by a mean ± SD of 19.5 ± 8.1 months, P= .034), including time until first dose escalation (by a mean ± SD of 12.0 ± 6.1 months, P= .037), and failure (by a mean ± SD of 20.7 ± 6.7 months, P= .034). Patients who increased the infusion frequency before increasing the dose remained on infliximab 8.4 months longer than those who first increased the dose (P= .045). Four patients experienced adverse events; 2 required discontinuation. Psoriasis Area and Severity Index, infliximab levels, and antibody titers were not measured. Dose escalation optimizes durability of infliximab. The probability of maintaining response is enhanced by concomitant methotrexate and increasing the infusion frequency before increasing the dose.