Objectives Strontium ranelate (SrRan) has demonstrated a structure-modifying activity associated with symptomatic improvement in patients with knee osteoarthritis (OA) the SEKOIA study). The aim of this analysis was to describe the proportion of patients in whom radiological OA progression was prevented in each treatment group, when considering different cut-offs of JSN.
Methods SEKOIA study included patients with symptomatic primary knee OA (Kellgren and Lawrence [KL] grade 2 or 3, joint space width [JSW] 2.5–5 mm) randomly allocated to SrRan 1 or 2 g/day, or placebo. Primary endpoint was radiographic change in JSW of the medial tibiofemoral compartment from baseline to LOCF. JSW was measured yearly using a validated computer-assisted centralised reading method. Patients with no relevant radiological OA progression were defined as those with a JSW loss between baseline and End, lower than 0.1 mm (JSN ≥-0.1 mm), or 0.2 mm (JSN ≥-0.2 mm) or 0.3 mm (JSN≥-0.3 mm). Patients who withdrew from the study were counted as non-responder patients. SrRan 1g and SrRan 2g treatment groups were compared to placebo using a chi² test.
Results ITT set included 1371 (82%) patients. Age was 63±7 years, BMI was 30±5 kg/m2, JSW was 3.5±0.8 mm. 61% were KL II. 69% were female. A significantly greater proportion of patients in both SrRan groups had no radiological progression as compared to placebo: 40.5% and 44.1% vs. 32.8% of responders respectively (p=0.006 and p=0.003) when applying the 0.3 mm threshold. In other words, the proportion of responders compared to placebo increased by 24% and 34% in the SrRan 1g and 2g groups respectively, with a number of patients needed to be treated (NNT) of 13 and 9 respectively. Similar differences between groups were observed for responders at additional JSN cut-offs:
Conclusions Treatment with SrRan is associated with a significantly greater number of patients without OA radiological progression over 3 years.
Disclosure of Interest J. Reginster Consultant for: Servier, Novartis, Negma, Lilly, Wyeth, Amgen, GSK, Roche, Merckle, Nycomed, NPS, Theramex, UCB, Paid instructor for: Merck Sharp and Dohme, Lilly, Rottapharm, IBSA, Genevrier, Novartis, Servier, Roche, GlaxoSmithKline, Teijin, Teva, Ebewee Pharma, Zodiac, Analis, Theramex, Nycomed, Novo-Nordisk, F. Berenbaum Grant/research support from: Servier, P. Nash Grant/research support from: Servier, Paid instructor for: Servier, O. Zamani: None Declared, M. Cohen-Solal: None Declared, G. Bianchi Grant/research support from: Servier, J. Branco Grant/research support from: Servier, F. Navarro: None Declared, C. Cooper Consultant for: Amgen, ABBH, Eli Lilly, GSK, MSD, Novartis, Pfizer, Roche, Shire, Servier, Paid instructor for: Amgen, ABBH, Eli Lilly, GSK, MSD, Novartis, Pfizer, Roche, Shire, Servier