Safety and Efficacy of Adalimumab (D2E7) in Crohn's Disease Patients with an Attenuated Response to Infliximab

Abstract
Although infliximab is highly effective in the treatment of Crohn's disease (CD), attenuated response to infliximab may develop over time in a subgroup of patients. The aim of our study was to examine the safety and efficacy of adalimumab (D2E7), a fully humanized anti-TNF-α Ab, in CD patients who had experienced an attenuated response to infliximab. Fifteen patients with active CD who experienced an attenuated response to infliximab were treated with adalimumab over a 6-month period. Patients, received a loading dose of 80 mg subcutaneously followed by 40 mg every 2 wk. The clinical response to adalimumab was classified as complete response, partial response, or nonresponse. Two patients received the loading dose of adalimumab but did not have adequate follow-up evaluations. Of the remaining 13 patients, 7 (54%) had a complete response, 4 (31%) had a partial response, and 2 (15%) were nonresponders. In six patients, the maintenance dose was increased in order to maintain clinical response. Eight of 11 (73%) patients on concurrent corticosteroids were able to discontinue or significantly decrease the dose of the steroids. Adalimumab was well tolerated without signs or symptoms of allergic reaction except in two patients who developed an injection site reaction. Our preliminary data suggest that adalimumab may be a safe and effective therapy for patients with CD who have experienced an attenuated response to infliximab.