2014 Volume 33 Issue 1 Pages 19-24
Objective: Synvisc® is a cross-linked hyaluronan preparation with higher viscosity than existing hyaluronan preparations and with more powerful and longer-lasting analgesic effects. The objective of this study was to evaluate the efficacy and safety of Synvisc® in patients persistently experiencing pain after treatment with an existing hyaluronan preparation (Artz®).
Methods: Subjects included 45 patients (70 knee joints) with osteoarthritis of the knee with persistent pain after treatment with Artz®. Synvisc® was administered three times at weekly intervals. Visual analog scale (VAS) was recorded before treatment and after 1 week, 2 weeks, 3 months and 6 months, respectively. Japanese Orthopedic Association (JOA) score was recorded before treatment and after 6 months. These scores were then analyzed accordingly.
Results: JOA scores improved significantly (from 76.9 to 81.9) after 6 months compared to before treatment. VAS scores during movement improved significantly after 1 week, and continued to improve up to 6 months (from 51.6 to 36.6). However, no significant effect was seen in the severe osteoarthritis group (Kellgren-Lawrence Grade III or IV; 23 patients) or in the group given Artz® for ≥ 1 year (31 patients). One of the 45 Synvisc® patients experienced a local adverse event.
Conclusions: Synvisc® is a useful medication in patients who do not respond adequately to Artz®. Efficacy was low in cases with severe deformation or persistent osteoarthritis, potentially representing a limitation of hyaluronan preparations in general. More local adverse events were seen with Synvisc® than with Artz®. Synvisc® should therefore be used with caution, taking account of the potential risks and benefits.
