Beyond Boundaries of a Trial: Post-Market Clinical Follow-Up of SOYA Patients

Background/Objectives: osteoarthritis (OA) is a leading cause of disability. With an aging population and rising obesity rates, OA presents a growing challenge to health systems worldwide. Current OA treatments involve a mix of pharmacological and nonpharmacological interventions. Viscosupplementation with hyaluronic acid (HA) has proven effective, especially in knee OA, leading to its recommendation in international guidelines. This study investigates the sustained benefits of a single intra-articular HA injection beyond one year in patients coming from the SOYA trial, considering the EU MDR 2017/745 emphasis on post-market follow-up. Methods: A prospective, observational, open, post-marketing study in a cohort of patients that participated in the SOYA trial. Follow-up was carried out by means of a telephone survey, and the data were anonymized and coded so that patients could not be identified. The study was approved by the Alcorcón Hospital Institutional Review Board (Alcorcón, Madrid, Spain). Results: In the follow-up of the SOYA trial, 81.5% of patients sustained positive effects for over 6 months after the trial ended. This correlated with improved daily functioning, enhanced mood, and high patient satisfaction. Younger age and milder OA grades were associated with prolonged treatment effects. Notably, 82% of patients with >6 months of improvement did not require additional medication. Conclusions: the results of this study support the safety and performance of Adant^® Plus as a treatment for patients with mild and moderate knee OA, with results lasting more than one year. Post-marketing studies are particularly relevant to examine the experience gained with the use of the device in routine clinical practice.