Long-term efficacy, safety, and tolerability of three-times weekly dosing regimen of glatiramer acetate in relapsing-remitting multiple sclerosis patients: 5-year results of the Glatiramer Acetate Low-Frequency Administration (GALA) open-label extension study (P6.378)

Objective: To describe the long term effects of early start (ES) and delayed start (DS) of GA40 treatment over 5 years in the GALA study. Background: The 1-year placebo-controlled (PC) phase of the Glatiramer Acetate Low-frequency Administration (GALA) study showed that glatiramer acetate 40 mg/mL three-times weekly (GA40) significantly reduced the annualized relapse rate (ARR) by 34% and MRI activity by 34.7% versus placebo in patients with relapsing-remitting multiple sclerosis (RRMS). Design/Methods: Clinical evaluations occurred every 6 months; a follow-up MRI was offered at Year 3. ARR was the primary endpoint; additional endpoints included gadolinium-enhancing (GdE) T1 lesions and new/enlarging T2 lesions. For efficacy statistical analyses, information from the entire exposure from randomization until last available observation was taken into account for both ES and DS groups. For safety, exposure only under GA was considered. Results: A total of 580 of 834 ES patients (70% of patients continuing into the OL phase) and 261 of 419 DS patients (62% of patients continuing into the OL phase) completed the GALA OL extension study, with a median GA exposure of 5 years. The most common AEs, injection-site reactions and immediate post-injection reactions, were generally mild and consistent with the well-established GA safety profile. The overall ARR during the entire long-term follow-up period since randomization was low (ES: 0.26, DS: 0.32, P =.041). Similarly, the increase from baseline in cumulative number of new/enlarging T2 lesions during 36 months since randomization was lower for ES compared with DS (5.67 vs. 8.47, P Conclusions: In the GALA open-label, long-term follow-up, no new or unexpected AEs emerged in patients receiving GA40 for up to 5 years. Treatment with GA40 was associated with low clinical and MRI disease activity in both patients continuing on GA40 and patients switching from placebo to GA40. Study Supported by: Teva Pharmaceutical Industries Disclosure: Dr. Alexander has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Employee of Teva. Dr. Beygi has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Employee of Teva. Dr. Feldman has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Employee of Teva. Dr. Ashtamker has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Employee of Teva.