Abstract

Purpose: In several clinical trials, bioactive collagen peptide (BCP) supplementation has demonstrated a positive effect on pain and mobility in osteoarthritic patients. This effect was explained by the excellent bioavailability of the peptides and their stimulatory impact on extracellular matrix synthesis. So far, however, there is a lack of clinical data on the role of BCP in a secondary preventive approach. For this reason, two prospective, randomized, placebo-controlled multi-center phase III studies were carried out to evaluate the efficacy of BCP intake on activity-related or functional joint pain in subjects not diagnosed with any joint diseases. Methods: The first study included 160 athletes (mean age 24) of both genders with activity-related knee pain (> 20mm VAS). Over the study period of 12 weeks, participants ingested 5g of BCP (FORTIGEL® GELITA AG, Germany) per day or placebo. As primary outcome variables, changes in pain intensity during activity were defined, as assessed by the study participants and the attending physicians using a visual analogue scale (0–100 mm VAS). In addition, changes in “pain at rest, changes in knee joint mobility, and the use of additional treatments (physiotherapy, ice packs, etc.) were considered as secondary end-points. In the second study, 182 men and women with a mean age of 50 suffering from functional knee or hip pain (> 3 NRS) participated. Primary endpoints of the study on elderly subjects were changes in joint pain during walking and pain at rest, assessed by the physicians on a 1–10 numeric rating scale (NRS). As the secondary end-point of the study, “pain after standardized physical stress” was assessed by the attending physicians, and several questions addressing joint discomfort and joint stiffness were evaluated by the participants using the NRS.
Results: In both studies, a statistically significant (p < 0.05) improvement for all primary endpoints could be demonstrated after BCP treatment compared with placebo and, in both studies, the efficacy of BCP treatment was confirmed for the ITT and PP population. In the athlete study, activity-related knee pain was statistically significantly reduced by 37.5% (participants’ assessment) and 33.8% (physicians' assessment) although, as expected, a pronounced placebo effect of about 25% pain improvement was determined. The secondary end-points of this trial confirmed the positive effect of BCP treatment in principle, even if not every result reached the level of statistical significance. In the trial with subjects suffering from functional knee and hip-joint pain, the data evaluation for the primary end-points of the study “pain during walking” and “pain at rest” showed an improvement of 38% for activity-related pain, and 39% for “pain at rest” after a 5g BCP treatment over 12 weeks. Although a pronounced placebo effect could be determined (25.6% improvement for pain during activity, and 18.6% for “pain at rest”), the BCP intake was statistically and significantly (p < 0.05) more effective for both primary end-points when a group comparison with placebo was carried out. For “pain during walking”, an effect size of d = 0.841 was calculated compared with the baseline situation, and for “pain at rest”, a value of d = 0.628 was determined. A detailed analysis of the secondary end-point of the study revealed that, for 12 of the 15 tested parameters, the improvement in joint pain, joint stiffness, and movement restriction was more pronounced after a BCP intake compared to placebo. Particularly for “pain after standardized physical stress”, “pain and movement restriction when crouching down” and “pain when walking”, a statistically significant improvement (p < 0.05) after a 12-week BCP supplementation was determined compared to placebo.
Conclusions: In conclusion, both RCTs clearly demonstrate the efficacy of a daily intake of 5 g of specific bioactive collagen peptides on pain reduction in subjects suffering from in activity-related or functional joint discomfort. The data suggest that a BCP treatment over a longer period of time is effective in individuals putting their joints under stress, or individuals with a certain risk of developing a degenerative joint disease in the foreseeable future. Therefore, a BCP supplementation might be an interesting option as a secondary preventive approach for the treatment of functional joint pain. (geändert)