Alemtuzumab is a humanized IgG monoclonal antibody approved in more than 60 countries for patients with relapsing remitting multiple sclerosis (RRMS). In phase 2 and 3 clinical trials (CAMMS223 (NCT00050778), CARE-MS I (NCT00530348), and CARE-MS II (NCT00548405)), patients receiving alemtuzumab demonstrated significantly greater improvements on clinical and MRI outcomes versus SC IFNβ-1a; mild to moderate infusion-associated reactions (IARs) were the most frequently reported adverse events (AEs) associated with alemtuzumab. EMERALD (NCT02205489) was a phase 4, multicenter, multinational, single-arm study designed to assess an algorithm for the prevention and management of IARs in RRMS patients treated with alemtuzumab.
Patients were treated with a study regimen of enhanced IAR prophylaxis relative to phase 2 and 3 studies. H1 and/or H2 antagonists or equivalent gastroprotection (proton pump inhibitors) were given 1 day before alemtuzumab infusion, 1 h prior to the infusion, and post-infusion. Methylprednisolone was given orally 1 day before infusion, 1 h prior to the infusion, and as needed post-infusion. Antipyretics were given 1 h before infusion and as needed post-infusion. Anti-emetics and normal saline were given as needed during and post-infusion.
Of the 61 patients screened, 58 (95.1%) were enrolled into the study. Of the 58 patients who received the first infusion of Period 1, 57 (98.3%) completed the 5 days of Course 1. A total of 54 patients received the first infusion of Period 2 and 53 completed the 3-day course. All patients (n = 58) completed the Month 6 visit and 54 the Month 12 visit. 93.1% of patients had at least one IAR (91.4% in Period 1 and 81.5% in Period 2), the majority of which were grade 1 (69.1%) or grade 2 (28.0%). The three most common IARs of headache, pyrexia, and rash occurred in 48.8%, 40.7%, and 24.1% of patients during the first course and 14.8%, 17.2%, and 5.6% of patients during the second course, respectively. The majority of IARs occurred within 6 h after the start of alemtuzumab infusion, with a peak during the first 2 h. The types and overall incidence of IARs were consistent with phase 2 and 3 trials. Frequency and distribution of rash were reduced in the EMERALD study compared with previous clinical trials. Serious IARs occurred in 15.5%, a higher rate than reported in clinical trials of alemtuzumab.
Although most alemtuzumab-treated patients experienced IARs as in previous controlled clinical studies, there was an improvement in the frequency and distribution of alemtuzumab-associated rash, which may have been associated with this study's prophylaxis regimen.