391 patients with mild-moderate knee osteoarthritis (K-L grade I-III) were randomized to three different intra-articular injection groups: 1x4mL injection of hylastan, 2x4mL injections of hylastan separated by two weeks, or an injection of methylprednisolone acetate 40mg. Patients were followed-up for 26 weeks after the first injection. Pain relief was significant in all three groups after 4 weeks and was retained throughout follow-up, although there were no differences noted between groups for the duration of follow-up. Safety profiles were similar between groups, with arthralgia, and joint stiffness and swelling representing the most common treatment-emergent adverse events. Average daily rescue medication use (acetaminophen) was higher in the hylastan treated groups compared to steroid, reaching statistical significance within the 2x4mL hylastan group. Currently, hylastan is only marketed in Italy.