POS0282 EVALUATION OF A NEW HYALURONATE FORMULATION ONE YEAR AFTER SINGLE INJECTION TO PATIENTS WITH SYMPTOMATIC KNEE OSTEOARTHRITIS (SOYA STUDY)

Background: Osteoarthritis (OA) is a leading cause of chronic pain and disability, and its prevalence is expected to increase worldwide (1) being the knee the most affected joint, especially in older adults. Intra-articular hyaluronic acid (HA) could be of particular benefit in OA patients with co-morbidities, and in case of inadequate response to other pharmacological treatments (2). HA has been generally administered in cycles of 3-5 injections, however, due to the pressure on public health systems, the trend is to reduce the number of injections maintaining the duration of effects as longer as possible. Objectives: To assess the effectiveness and safety of a new formulation of HA, up to one year after one single injection to patients in the SOYA (Symptomatic Osteoarthritis one Year Assessment) study. Methods: Patients with Kellgren-Lawrence (KL) grade 2-3 and Visual Analogue Scale (VAS) pain >=40-<80mm were prospectively included to receive a single injection of MPS-HA2%. At 6m a second injection could be offered to selected patients. Primary outcome was reduction of VAS pain in the target knee. VAS for joint pain and WOMAC were recorded at 6 and 12m; Minimally Clinical Important Improvement MCII (>=20% relative change for VAS pain) and patient and investigator assessments (PGA, IGA) (Likert scale 0-4 points) were also estimated. Adverse events were recorded for safety assessment. Results: One hundred and one patients (mean age 68 years, 74% female and 78% with overweight) were included. Mean pain at baseline in the target knee was 63.57mm and 57% were grade 3 KL with a mean evolution of 7.5 years. Table 1 shows the improvement in VAS and WOMAC scores at 6 and 12 months in the mITT population. Similar results were obtained in PP population. Table 1. Changes in VAS and WOMAC scores, expressed as mean values SCORE Baseline 6 months 12 months value value % variation (95% CI) value % variation (95% CI) VAS pain 63.57 37.59 -39.74* (-49.23; -30.25) 38.37 -37.67* (-47.82; -27.52) WOMAC total 50.19 31.88 -37.96* (-46.83; -29.09) 31.65 -36.47* (-46.20; -26.73) pain 49.37 32.01 -32.92* (-43.37; -22.46) 31.08 -32.07* (-43.19; -20.95) stiffness 49.12 28.35 -35.24** (-53.22; -17.23) 28.71 -34.08* (-49.30; 18.86) function 52.07 35.30 -33.95* (-43.49; -24.40) 35.15 -32.71* (-42.80; -22.62) *p-value: 0.0001; **p-value: 0.0002. Student test The MCII was achieved by 66.3% of patients at 6m and 62.2% at 12m. Regarding PGA mean score was 2.44 at baseline, 1.35 at 6m and 1.46 at 12m (Wilcoxon, p-value <0.05). As for the IGA mean score was 2.29 at baseline, 1.06 at 6m and 1.48 at 12m (Wilcoxon, p-value <0.05). Fourteen patients received a second injection at 6m and 50% of them achieved at 12m a significant and clinically relevant improvement compared to baseline, above the 20% established for the MCII. In total, 12 adverse events (8 patients) were reported, all of them local, non-serious, and of mild-moderate intensity. Conclusion: Viscosupplementation with a single intra-articular injection of MPS-HA2% has proven to be effective and well tolerated up to 12 months after treatment. The re-infiltration of the joint in appropriate cases has proven to be effective in a significant number of patients. The acceptability of the treatment by the patient was optimal. References: [1]Sebbag E, Felten R, Sagez F, et al. The world-wide burden of musculoskeletal diseases: a systematic analysis of the World Health Organization Burden of Diseases Database. Ann Rheum Dis. 2019 Jun;78(6):844-848. [2]Bruyère O, Cooper C, Pelletier JP, et al. An algorithm recommendation for the management of knee osteoarthritis in Europe and internationally: a report from a task force of the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis (ESCEO). Semin Arthritis Rheum. 2014 Dec;44(3):253-63. Disclosure of Interests: Carlos Gavín: None declared, Francisco Moreno: None declared, Francisco J. Blanco: None declared, José Luis Pablos: None declared, Miguel A. Caracuel-Ruiz: None declared, Jose Rosas: None declared, Pablo Hernández-Esteban: None declared, Francisco Navarro: None declared, PILAR CORONEL Employee of: Meiji Pharma Spain, S.A., Mercedes Gimeno Employee of: Employee of Meiji Pharma Spain, S.A.