Intra-articular injection of non-animal stabilised hyaluronic acid (NASHA) for osteoarthritis of the hip: a pilot study.

OBJECTIVES This study was undertaken to assess the safety and potential efficacy of intra-articular non-animal stabilised hyaluronic acid (NASHA) in patients with hip OA. METHODS This was a prospective, open-label, 3-month pilot study of a single intra-articular injection of NASHA in 31 patients. Safety outcomes were measured at 2 weeks and 3 months after treatment, as were efficacy measurements including WOMAC pain, stiffness and physical function scores, and the patient assessment of global disease status. Patients demonstrating reduced pain at month 3 participated in an extension phase (assessment at 6-11 months, 18 patients). Positive response was defined as a > or = 40% reduction in the WOMAC pain score from baseline, together with an absolute decrease of > or = 5 points. RESULTS Intra-articular injection of NASHA into the hip was well tolerated. The only treatment-related AE was exacerbation of pain and/or stiffness in the treated hip (reported by 9 patients) and there were no serious AEs. The response rate to treatment was 50% at 2 weeks and 54% at 3 months. In the extension population, response rates of 69% and 44% were observed at month 3 and the extension visit, respectively. Global disease status was improved at month 3 compared with baseline in 68% of the patients. CONCLUSIONS Our results show that a single intra-articular injection of NASHA is a well tolerated and potentially effective therapy in the treatment of hip OA. Further studies of NASHA in this setting are warranted.