A narrative review on the safety of glatiramer acetate in multiple sclerosis: focus on Europe

Glatiramer acetate (GA) has been a pivotal therapy for relapsing multiple sclerosis (MS) due to its favorable safety profile. Long-term data spanning decades demonstrate its continued use in diverse patient populations. Adverse events include manageable localized injection site reactions, lipoatrophy or necrosis, and rare cases of liver injury. GA has minimal effects on immune function, and does not increase the risk of opportunistic infections, making it suitable for MS patients at risk for infections or reactivation of latent infections. GA's immunomodulatory properties may pose a lower infection risk than other disease-modifying treatments. Progressive multifocal leukoencephalopathy risk with GA is low, and screening for latent infection is unnecessary before treatment. Vaccination is important for preventing infections in MS patients. GA does not compromise vaccine efficacy and is compatible with both inactivated and live attenuated vaccines. Special populations that may benefit from the characteristics of GA include older adults and patients with comorbidities and/or polypharmacy. MS patients often have comorbidities, necessitating careful management of potential drug interactions and side effects. Drug interactions with GA are not predicted, and clinical data suggest that the risk is low. GA is not contraindicated during pregnancy and exhibits a reassuring safety profile during breastfeeding, with no increased risk of adverse outcomes identified. Regulatory restrictions on GA use during breastfeeding have been removed. In summary, GA remains a safe and well-established therapy for MS patients, including those in special populations. Its favorable safety profile, compatibility with vaccination, and reassuring outcomes solidify its role in MS treatment.