Effect of polymerized-type I collagen in knee osteoarthritis. II. In vivo study

Polymerized-Type I Collagen (Polymerized-Collagen) is an anti-inflammatory and a tissue regenerator biodrug. The aim of the study was to evaluate the efficacy and safety of intra-articular injections of Polymerized-Collagen in patients with knee osteoarthritis (OA).

Patients (n=53) were treated with 12 intra-articular injections of 2 mL of Polymerized-Collagen (n=27) or 2 mL of placebo (n=26) during 6 months. Follow up period was 6 months. The primary endpoints included Western Ontario and McMaster University Osteoarthritis Index, Lequesne index, and pain intensity on a visual analogue scale (VAS). Secondary outcomes were patient global score, investigator global score and drug evaluation. Clinical improvement was determined if the decrease in pain exceeds 20 mm on a VAS and patients achieved at least 20% of improvement from baseline. Urinary levels of C-terminal crosslinking telopeptide of collagen type II (CTXII) and serum high-sensitivity C-reactive protein (hsCRP) were determined by enzyme immunoassays. Statistical analysis was performed by intention to treat.

Polymerized-Collagen was safe and well tolerated. Patients had a statistically significant improvement (P<0.05) from baseline vs. Polymerized-Collagen and vs. placebo at 6 months in: Lequesne Index (13.1+/-0.5 vs. 7.1+/-0.7 vs. 9.6+/-0.8; P=0.027), WOMAC (9.0+/-0.5 vs. 4.0+/-0.6 vs. 5.80+/-0.8; P=0.032), patient VAS (60.0+/-2.6 vs. 20.6+/-2.4 vs. 36.1+/-4.5; P=0.003), physician VAS (49.8+/-1.9 vs. 16.8+/-2.9 vs. 29.8+/-2.9; P=0.002), patient global score (1.08+/-0.1 vs. 2.7+/-0.1 vs. 1.9+/-0.2; P=0.028) and analgesic usage (30.1+/-9.4 vs. 11.0+/-3.4 vs. 17.9+/-4.9; P=0.001). This improvement was persistent during the follow up. A threefold increase in CTXII was determined in placebo group. No differences were found on hs CRP and incidence of adverse events between groups.

Polymerized-Collagen is safe and effective in the treatment of knee OA.