Efficacy and tolerability of an undenatured type II collagen supplement in modulating knee osteoarthritis symptoms

The study postulates that UC-II, a nutritional ingredient containing undenatured type II collagen, significantly improves knee function in osteoarthritis and is also well-tolerated.

Osteoarthritis is a very common form of arthritis affecting more than 25 million Americans. It is caused by the destruction of joint cartilage and remodeling of the adjacent bone. The treatment involves over the counter analgesics, a number of nonsteroidal anti-inflammatory drugs (NSAIDs), intra-articular injections of corticosteroids or hyaluronic acid, plus tramadol and other opioid analgesics so as to relieve the pain. These therapies may provide symptomatic relief for the short time. However, their final impact on the pathophysiologic progression of osteoarthritis (OA) is limited. Previous studies have reported Undenatured collagen (UC-II) to be efficacious for the treatment of arthritis. More recently, a statistically significant improvement in knee joint function over placebo was also reported in a clinical study comprising a group of healthy individuals, supplemented with UC-II, and who developed transient knee joint pain upon strenuous exercise. These same individuals also took longer to experience pain after 120 days of supplementation.

Rationale behind research:

Previous studies have reported the efficacy of UC-II in the treatment of arthritis. The current study was conducted so as to further explore the efficacy of UC-II in treating knee OA and also comparing it with placebo and glucosamine hydrochloride plus chondroitin sulfate (GC)

Objective:

To evaluate the efficacy and tolerability of UC-II for knee osteoarthritis (OA) pain and associated symptoms compared to placebo and to glucosamine hydrochloride plus chondroitin sulfate (GC).

Study outcomes

Primary endpoint: Primary endpoint was the change in total Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) from baseline through day 180 for the UC-II group versus placebo and GC.

Secondary endpoint: Secondary endpoint included the Lequesne Functional Index (LFI), the Visual Analog Scale (VAS) for pain and the WOMAC subscales. Modified intent-to-treat analysis were performed for all endpoints using analysis of covariance and mixed model repeated measures, while incremental area under the curve was calculated by the intent-to-treat method.

Outcomes

Baseline: Baseline subject characteristics, OA severity, serum CRP, COMP, IL-6 and other characteristics were similar among the three groups.

• Primary Outcomes:

Total WOMAC score: The UC-II supplemented group had statistically significant changes in the total WOMAC score compared to placebo and GC at day 180. When the total WOMAC results were analyzed, there remained a statistically significant difference between the UC-II and the placebo groups (−514 vs. −397; p = 0.0097). An iAUC analysis also yielded statistically significant differences between the UC-II group versus placebo. No significant changes were observed between the GC and placebo cohorts regardless of the type of analytical model used.

• Secondary Outcomes:

Total WOMAC score based on baseline COMP levels: Patients supplemented with UC-II, and presented with baseline COMP levels ≥285 ng/mL, had a greater reduction in the total WOMAC score than both placebo and GC groups with similar COMP levels under all modeling conditions.

WOMAC mean subscores: pain, stiffness and physical function: At day 180, there was significant reductions in all three WOMAC subscales for UC-II group compared to placebo: pain (24.0 vs. 17.0; p = 0.0003), stiffness (23.8 vs. 17.8; p = 0.004), and physical function (22.5 vs. 17.3; p = 0.007). The UC-II cohort also had significant reductions in WOMAC pain (24.0 vs. 19.2; p = 0.016) and stiffness (23.8 vs. 19.4; p = 0.044) at day 180 compared to GC.

Figure 1: WOMAC mean subscores—pain, stiffness and physical function

• Mean VAS score:The UC-II supplemented group had a significant decrease in mean VAS score at day 180 versus both placebo (22.6 vs. 17.0; p = 0.002) and GC (22.6 vs. 18.4; p = 0.025).
• LFI score: A significant reduction was observed in the LFI score for the UC-II group at day 180 versus placebo (2.9 vs. 2.1; p = 0.009). UC-II supplementation also has a greater improvement in LFI score versus GC (2.9 vs. 2.2; p = 0.008). No significant change was observed between the GC and placebo cohorts. Improvement in the total LFI score for the UC-II group was attributed to a significant reduction in the LFI subscale for daily activities at day 180.
  
  
  

The results presented from the current study demonstrate that individuals consuming UC-II presented with better clinical outcomes versus those supplemented with placebo or GC. Analysis of the WOMAC subscales showed that reductions in all three WOMAC subscales contributed to the improvement in the overall WOMAC score observed in subjects supplemented with UC-II. In contrast, GC supplementation failed to induce a statistically significant improvement in the WOMAC, VAS or LFI scores versus placebo. These results confirm previous findings by Crowley et al., which reported greater reduction in knee OA symptoms after 90 days of UC-II supplementation than what was observed with GC.