Spasticity improvement in patients with relapsing–remitting multiple sclerosis switching from interferon-β to glatiramer acetate: The Escala Study

Abstract Background A recent pilot study suggested spasticity improvement during glatiramer acetate (GA) treatment in multiple sclerosis (MS) patients who previously received interferon-β (IFN-β). Objective To evaluate changes in spasticity in MS patients switching from IFN-β to GA. Methods Observational, multicentre study in patients with relapsing–remitting MS (RRMS) and spasticity switching from IFN-β to GA. The primary endpoint comprised changes on Penn Spasm Frequency Scale (PSFS), Modified Ashworth Scale (MAS), Adductor Tone Rating Scale (ATRS), and Global Pain Score (GPS) at months 3 and 6 after starting GA. Results Sixty-eight evaluable patients were included (mean age,41.7 ± 9.5 years; female,70.6%; mean time from MS diagnosis to starting GA,7.6 ± 5.7 years). Previous treatments were subcutaneous IFN-β1a in 42.6% patients, intramuscular IFN-β1a in 41.2% and IFN-β1b in 32.4%, whose mean durations were 3.5 ± 3.3, 2.7 ± 2.5 and 4.4 ± 3.6 years, respectively. Statistically significant reductions in mean scores on all spasticity measurements were observed from baseline to month 3 (PSFS, 1.7 ± 0.9 vs 1.4 ± 0.6, p < 0.01; MAS, 0.7 ± 0.5 vs 0.6 ± 0.5, p < 0.01; highest MAS score, 1.9 ± 0.8 vs 1.7 ± 0.8, p < 0.01; ATRS, 1.6 ± 0.6 vs 1.4 ± 0.6, p < 0.01; GPS, 29.4 ± 22.1 vs 24.7 ± 19.4, p < 0.01) and from baseline to month 6 (PSFS, 1.7 ± 0.9 vs 1.3 ± 0.6, p < 0.01; MAS, 0.7 ± 0.5 vs 0.5 ± 0.5, p < 0.01; highest MAS score, 1.9 ± 0.8 vs 1.5 ± 0.9, p < 0.01; ATRS, 1.6 ± 0.6 vs 1.3 ± 0.6, p < 0.01; GPS, 29.4 ± 22.1 vs 19.1 ± 14.8, p < 0.01). Conclusion Spasticity improvement in terms of spasm frequency, muscle tone and pain can be noted after three months and prolonged for six months of GA treatment.