Efficacy and tolerability of metformin as an adjuvant therapy in patients with relapse-remitting multiple sclerosis receiving interferon Beta 1a: A randomized pilot trial.

BACKGROUND

Neurodegeneration and inflammation can accelerate the demyelination process in multiple sclerosis (MS). We aimed to investigate the efficacy and tolerability of metformin as an add-on treatment to interferon Beta 1a (IFNβ-1a) in Egyptian patients with relapsing-remitting multiple sclerosis (RRMS).

METHOD: Thirty RRMS patients were divided into two groups: the experimental arm receiving IFNβ-1a plus 2 g of metformin once daily and the control arm receiving IFNβ-1a alone. Tolerance to metformin was measured for the intervention group. Following 6 months period, serum neurofilament light chain (sNFL) and nuclear factor Kappa B (NF-κB), T2 lesions in magnetic resonance imaging (MRI), and expanded disability status scale (EDSS) were measured.

RESULTS

There were no statistically significant differences between the two groups in the change in the median (interquartile range) of the blood biomarkers (sNFL; -32.8 (21) vs -32.8 (13.4), p = 0.99) and NF-κB; -64.9 (35.1) vs -61.6 (35.7), p = 0.8, respectively). In clinical outcomes, there was no statistically significant in the mean (standard deviation) change of EDSS (0 vs 0, p = 1). For MRI results, 11 patients had a stationary and regressive course 1 patient had a progressive course in the metformin group vs 6 patients had a stationary and regressive course and 2 had a progressive course in the control group, p = 0.23. All outcomes were measured after 6-month follow-ups. The most common side effects of metformin were diarrhea and abdominal pain without incidence of lactic acidosis.

CONCLUSION

Receiving metformin as an add-on therapy to IFNβ-1a did not result in a significant improvement in neurodegeneration and inflammation blood biomarkers and clinical outcomes. A high dose of metformin (2 g/day) is safe and well tolerated in patients with MS. Additional studies involving larger populations are necessary to confirm or disprove these findings.

TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT06812585.