EVALUATION OF THE EFFICACY AND SAFETY OF A GLYCOSAMINOGLYCAN-PEPTIDE COMPLEX IN THE TREATMENT OF KNEE OSTEOARTHRITIS IN PATIENTS WITH PREVIOUS INEFFICIENCY OF SLOW-RELEASE ORAL ANTI-INFLAMMATORY DRUGS (THE MULTICENTER OPEN-LABEL STUDY PRIMULA: USE OF RUMALON® WITH INITIALLY SMALL SUCCESS IN THE TREATMENT OF OSTEOARTHRITIS)

Glycosaminoglycan-peptide complex (GPC) (Rumalon®) is an injectable slow-release anti-inflammatory agent (SRIA) that has complex anti-inflammatory and metabolic effects. GPC has been successfully used in the treatment of osteoarthritis (OA) for several decades. The agent now returns again to Russian clinical practice. Objective: to evaluate the efficacy and tolerability of GPC in patients with knee OA, in whom other SRIAs have been previously ineffective.Subjects and methods. A study group consisted of 104 patients (92.3% women) (mean age, 63.2±8.5 years; body mass index (BMI), 28.5±5.4 kg/m2) with severe joint pain (≥40 mm on a 100-mm visual analogue scale (VAS)) and/or the need to regularly use nonsteroidal anti-inflammatory drugs (NSAIDs). All the patients received oral SRIAs in the last 6 months and had no improvement. At baseline, VAS pain intensity was 59.4±13.1 mm; the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain was 227.3±90.8; WOMAC stiffness, 97.9±42.1; WOMAC function, 769.2±326.1; total WOMAC scores, 1095.1±426.6. GPC was used by the standard scheme: 25 intramuscular injections every other day per treatment cycle; the results of treatment were assessed at 8 and 12 weeks by VAS and WOMAC pain scores, needs for NSAIDs, satisfaction with treatment (measured on a 1- to 5-pont scale where 1 = no improvement or deterioration and 5 = the best result).Results and discussion. At 8 and 12 weeks, VAS pain scores decreased by 30.1±18.3% and 36.9±16.9%, respectively; the reductions in WOMAC pain scores were 29.8±16.3 and 38.2±23.4%; WOMAC stiffness scores, 29.2±15.4 and 31.6±17.4%; WOMAC function scores, 27.7±14.7 and 30.6±18.4%; and total WOMAC scores, 27.2±13.5 and 33.6±18.0%. The changes in pain intensity and WOMAC scores were statistically significant in both followup periods (p<0.001). The majority of patients rated their treatment result as good or excellent: 70.2% at 8 weeks and 75.9% at 12 weeks. 31.7% of the patients completely stopped taking NSAIDs at 12 weeks. Two patients were noted to have adverse reactions (pain at the injection site and allergic skin reaction) that did not require treatment discontinuation and completely resolved without consequences after completion of a GPC treatment cycle. Conclusion. GPC is an effective and safe agent for the treatment for OA, as well as in patients with severe OA and inefficiency of oral SRIAs