Long-term efficacy and safety of three times weekly dosing regimen of glatiramer acetate in relapsing multiple sclerosis patients: Seven-year results of the Glatiramer Acetate Low-frequency Administration (GALA) open-label extension study

Peter Rieckmann; Robert Zivadinov; Alexey Boyko; Krzysztof Selmaj; Jessica K Alexander; Shaul Kadosh; Svetlana Rubinchick; Emily Bernstein-Hanlon; Yafit Stark; Natalia Ashtamker; Mat D Davis; Omar Khan

doi:10.1177/20552173211061550

Long-term efficacy and safety of three times weekly dosing regimen of glatiramer acetate in relapsing multiple sclerosis patients: Seven-year results of the Glatiramer Acetate Low-frequency Administration (GALA) open-label extension study

Mult Scler J Exp Transl Clin. 2021 Dec 13;7(4):20552173211061550. doi: 10.1177/20552173211061550. eCollection 2021 Oct.

Authors

Affiliations

¹ Medical Park, Loipl, Germany.
² Buffalo Neuroimaging Analysis Center, Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, NY, USA.
³ Federal Centre of Brain Research and Neurotechnology, Moscow, Russia.
⁴ Department of Neurology, University of Warmia and Mazury, Olszytn and Center of Neurology, Lodz, Poland.
⁵ Teva Pharmaceuticals, West Chester, Pennsylvania, USA.
⁶ Teva Pharmaceuticals, Netanya, Israel.
⁷ Wayne State University, Detroit, MI, USA.

Abstract

Objective: Describe the long-term outcomes of early-start (ES) and delayed-start (DS) glatiramer acetate 40 mg/mL treatment three times weekly (GA40) for up to seven years in the Glatiramer Acetate Low-frequency Administration (GALA) study in patients with relapsing multiple sclerosis (RMS).

Methods: Patients were evaluated every three to six months. The primary efficacy endpoint was annualized relapse rate (ARR); additional endpoints were exploratory or post hoc. For efficacy, data from the entire exposure period were used for the ES and DS cohorts. For safety, exposure only under GA40 was considered.

Results: Of the patients who continued into the open-label extension (OLE), 580/834 (70%) ES and 261/419 (62%) DS completed the OLE. For the entire placebo-controlled and OLE study period, ARR was 0.26 for ES and 0.31 for DS patients (risk ratio = 0.83; 95% confidence interval [CI]: 0.70-0.99). ES prolonged median time to first relapse versus DS (4.9 versus 4.3 years; hazard ratio = 0.82; 95% CI: 0.6-0.96). OLE-only results showed DS patients experienced similar efficacy for relapse and disability outcomes as ES patients. Adverse events were consistent with the well-established GA safety profile.

Conclusions: GA40 treatment conferred clinical benefit up to seven years, resulting in sustained efficacy and was generally well tolerated in RMS patients.

Keywords: disability; disease-modifying therapy; glatiramer acetate; multiple sclerosis; open-label extension; relapse.