To evaluate long term efficacy of three iterative courses of three weekly intra-articular (IA) injections of NRD101 in the treatment of symptomatic knee osteoarthritis (OA).
A 1 year prospective, multicentre, randomised, double blind, placebo controlled study of 301 patients aged >50 years with painful and radiological medial knee OA. Patients were randomly assigned into three groups receiving: (1) three courses of three IA injections of hyaluronic acid (HA) + oral placebo; (2) IA injections of saline solution + diacerein 100 mg/day; (3) IA injections of saline solution + oral placebo. Demographic data and symptomatic criteria-pain, Lequesne's index, patient's global assessment of disease activity, percentage of painful days-were obtained during the study; primary structural criterion was JSW. Efficacy criteria were changes in pain VAS, joint space narrowing (JSN), and percentage of progressors (JSN >0.5 mm). An intention to treat analysis was used for symptomatic variables, and completer analysis for structural variables.
Baseline characteristics were similar between the three groups. Mean (SD) improvement in pain VAS was clinically relevant (-33.9 (27.3), n = 301), but with no difference between the groups (p = 0.96). JSW deteriorated (-0.09 (0.55) mm, n = 277, p = 0.01), but with no difference between the groups (p = 0.82). Percentages of progressors were 17.7, 18.9, and 20.3% (p = 0.90), in groups 1, 2, and 3, respectively.
A weak but statistically significant structural deterioration occurred over 1 year, together with clinically relevant symptomatic improvement in patients receiving oral drug and iterative IA injections. Symptomatic and/or structural effects for both this new HA compound and diacerein were not demonstrated.