Natalizumab is a recombinant humanized monoclonal antibody, that binds to the integrin α4-subunit, inhibits the adhesion of lymphocytes to vascular endothelial cells and their infiltration into the central nervous system. In April 2021, a subcutaneous form of natalizumab, which until recently could only be administered intravenously, was registered in the European Union. Due to a shorter and simpler administration regimen, greater patient comfort and reduced healthcare costs, subcutaneous natalizumab is a highly convenient form of therapy, both for patients and healthcare professionals. The subcutaneous form is also an alternative for patients with difficult venous access. In this paper, we present four patients with relapsing-remitting multiple sclerosis of different duration, treated with natalizumab. The presented clinical cases are a summary of the first Polish experiences with subcutaneous natalizumab.