Randomised, controlled trial of avocado-soybean unsaponifiable (Piascledine) effect on structure modification in hip osteoarthritis: the ERADIAS study.

OBJECTIVE: To assess the ability of avocado-soybean unsaponifiable-Expanscience (ASU-E) to slow radiographic progression in symptomatic hip osteoarthritis (OA). METHODS: Prospective, randomised, double blind, parallel group, placebo controlled 3 year trial. Patients with symptomatic (painful ≥1 year, Lequesne Index between 3 and 10) hip OA (American College of Rheumatology criteria) and a minimum joint space width (JSW) of the target hip between 1 and 4 mm on a pelvic radiograph were randomly assigned to 300 mg/day ASU-E or placebo. Standing pelvis, target hip anteroposterior (AP) and oblique views were taken annually. The primary outcome was JSW change at year 3, measured at the narrowest point on pelvic or target hip AP view (manual measure using a 0.1 mm graduated magnifying glass). The full analysis dataset (FAS) included all patients having at least two successive radiographs. An analysis of covariance Mixed Model for Repeated Measurements with Missing at Random (for missing data) was performed to compare adjusted 3 year JSW changes (primary outcome) and the percentages of 'progressors' (JSW loss≥0.5 mm) between groups. RESULTS: 399 patients were randomised (345 kept in the FAS), aged 62 (35-84) years, 54% women, mean body mass index 27 (SD 4) kg/m(2), mean symptom duration 4 (SD 5) years, 0-100 normalised Lequesne Index 30 (SD 9) and global pain visual analogue scale 37 (SD 23) mm. Mean baseline JSW was 2.8 (0.9) mm. There was no significant difference on mean JSW loss (-0.638 mm vs -0.672 mm, p=0.72, in the ASU-E and placebo groups, respectively) but there were 20% less progressors in the ASU-E than in the placebo group (40% vs 50%, respectively, p=0.040). No difference was observed on clinical outcomes. Safety was excellent. CONCLUSIONS: 3 year treatment with ASU-E reduces the percentage of JSW progressors, indicating a potential structure modifying effect in hip OA to be confirmed, and the clinical relevance requires further assessment.

Structural effect of avocado/soybean unsaponifiables on joint space loss in osteoarthritis of the hip.

OBJECTIVE: To evaluate the structural effect of avocado/soybean unsaponifiables (ASU) in the treatment of patients with symptomatic osteoarthritis (OA) of the hip. METHODS: Patients with regular painful primary OA of the hip (European League Against Rheumatism 1980 criteria) and a joint space still > or = 1 mm (Kellgren grade 1 to 3, assessed by an independent observer prior to inclusion) entered a prospective, multicenter, randomized, parallel group, double-blind, placebo-controlled trial of 2 years duration. Patients had at least a 6-month history of regular pain and an algofunctional index (AFI) > or = 4. The primary assessment criterion was a decrease of the joint space width (JSW) on plain anteroposterior radiographs of the pelvis performed in standing position, measured at the narrowest points by 2 independent readers, previously tested and selected and blinded to both the treatment and the time sequence. Secondary criteria were standard clinical outcome measurements (AFI, pain on a visual analog scale, consumption of nonsteroidal antiinflammatory drugs and patient's and investigator's global assessments). RESULTS: One hundred sixty-three patients were included: 102 men and 61 women (mean age 63.2 +/- 8.7 years). A total of 108 patients (72 men and 36 women; mean age 64 +/- 7.9 years) were radiologically evaluable at 23.7 +/- 2.6 months (ASU group; n = 55) and 23.7 +/- 3.2 months (placebo group; n = 53). Overall comparison of the evolution of JSW showed no difference between the ASU and placebo groups, from 2.35 +/- 0.93 to 1.87 +/- 1.10 mm and from 2.5 +/- 0.94 to 1.9 +/- 1.33 mm, respectively (intergroup P value at end point = 0.9). When patients were divided into 2 subgroups according to the median value of the baseline JSW (2.45 mm), the joint space loss in the most severely affected subgroup of patients (baseline JSW < or = median) was significantly greater in the placebo group than in the ASU group: from 1.69 +/- 0.58 to 0.84 +/- 0.77 mm (-0.86 +/- 0.62 mm) and from 1.66 +/- 0.42 to 1.22 +/- 0.7 mm (-0.43 +/- 0.51 mm), respectively (P < 0.01). The JSW decrease was identical, with no difference in ASU and placebo groups, in the less severely affected subgroup of patients (baseline JSW > median). Clinical parameters in the 2 groups did not differ significantly throughout the study. CONCLUSION: This pilot randomized, double-blind, placebo-controlled trial failed to demonstrate a structural effect of ASU in hip OA. However, in a post-hoc analysis, ASU significantly reduced the progression of joint space loss as compared with placebo in the subgroup of patients with advanced joint space narrowing. These results suggest that ASU could have a structural effect but require confirmation in a larger placebo-controlled study in hip OA.