LYON, FRANCE—Teriflunomide does not interfere significantly with the serologic responses to recall antigens, allowing patients with multiple sclerosis (MS) treated with teriflunomide to mount effective immune responses to the seasonal flu vaccine. At the 28th Congress of the European Committee for Treatment and Research in MS (ECTRIMS), researchers presented the results of the phase II TERIVA study, which investigated the ability of patients with relapsing forms of MS receiving teriflunomide to respond to influenza vaccine and determine whether antigen responses were preserved under teriflunomide treatment.
Amit Bar-Or, MDCM, MSc, and colleagues conducted a multicenter, multinational, parallel-group study involving 128 patients in three treatment groups. Groups one and two included patients with relapsing forms of MS treated for at least six months with either teriflunomide 7 mg or 14 mg, respectively. Median treatment duration was 5.7 years for the 7-mg dose group and 5.8 years for the 14-mg dose group. Group three comprised patients with relapsing forms of MS treated for at least six months with a stable dose of interferon beta. Median treatment duration in this group was 5.7 years. Group three represented a reference population of patients who have been reported to mount normal immune responses to influenza vaccination.
A screening period of up to 21 days was followed by influenza vaccination with the 2011/12 seasonal influenza vaccine per country standard on day 1 with antibody assessments at day 28 postimmunization.
The primary efficacy end point was the proportion of patients who achieved seroprotection to influenza vaccine strains, as defined as an influenza antibody titre of 40 or more for each strain (H1N1, H3N2, B) 28 days postvaccination. Evaluation of vaccine effectiveness was based on European criteria for influenza vaccine efficacy. The study enrolled 122 patients: 40 in group one, 39 in group two, and 43 in group three.
Dr. Bar-Or, who is an Associate Professor and Director of the Experimental Therapeutics Program and Scientific Director of the Clinical Research Unit at Montreal Neurological Institute, and colleagues reported that more than 90% of patients achieved postvaccination antibody titres of 40 or above for H1N1 and B strains in all treatment groups. For H3N2, titres of 40 or above were achieved in 90% or more of patients in the teriflunomide 7-mg and interferon beta groups and in 77% of the patients in the teriflunomide 14-mg group.
The study revealed no new safety concerns with teriflunomide administration, and influenza vaccination was generally well tolerated by the study population. The overall incidence of treatment-emergent adverse events was higher in the interferon beta group (45.7%) than in the two teriflunomide groups (26.8% in the 7-mg group and 36.6% in the 14-mg group).
The researchers found that patients with relapsing forms of MS treated with teriflunomide mounted effective immune responses to seasonal flu vaccination. These responses, they note, were in accordance with the European criteria for efficacy of influenza vaccination in a population of 18- to 60-year-olds. Further, following influenza vaccination, no new safety concerns arose in patients receiving teriflunomide.
“These results, combined with data from the TEMSO study, support the view that teriflunomide appears to limit abnormal pathogenic T-cell responses effectively, and it does not interfere significantly with the serologic responses to recall antigens,” the researchers concluded.
—Glenn Williams
Vice President/Group Editor