Efficacy and Safety of Dietary Undenatured Type II Collagen on Joint and Motor Function in Healthy Volunteers: A Randomized, Double-Blind, Placebo-Controlled, Parallel-Group Study

Objective: Prevalence of osteoarthritis (OA) is increasing alarmingly worldwide. Slowing down the progression of OA and diverse locomotive organ disorders is gaining interest in improving the quality of life (QOL) and extending healthy life-span. In a pilot study, intake of a small amount of undenatured type II collagen exhibited suppression of damage to the articular cartilage via oral immune tolerance. It also demonstrated improvement of knee and joint flexibility and mobility with continued intake of undenatured type II collagen (NEXT-II®) derived from chicken sternum cartilage. This randomized, double-blind, placebo-controlled, parallel-group clinical investigation (RCT) evaluated the efficacy and safety of 12 weeks of regular intake of NEXT-II® on joint and motor function in healthy Japanese male and female participants (aged 20 to <75 years). Method: Sixty-four participants were randomized to receive either NEXT-II® (undenatured type II collagen 3.2 mg/d) or placebo over a period of 12 consecutive weeks. Efficacy on joint and motor functions were evaluated measuring knee passive range of motion as the primary outcome; the Japan Knee Osteoarthritis Measure (JKOM), Visual Analog Scale (VAS) for knee discomfort, and motor functions (10-meter walking and stair-climbing test) as the secondary outcomes; and Japan Low back pain Evaluation Questionnaire (JLEQ) and VAS for lower back discomfort as the exploratory outcomes. Results: Fifty-eight participants (placebo = 28; NEXT-II® group = 30) completed the study. In the assessment of knee passive range of motion, significant improvements in “flexion” and “flexible angle (range)” were observed in the NEXT-II® group at 4, 8, and 12 weeks of treatment. NEXT-II® induced significant improvements in JKOM, VAS for knee and lower back discomfort, 10-meter walking test, stair-climbing test, and JLEQ. Conclusions: Results demonstrate that undenatured type II collagen is safe and efficacious in improving knee flexibility and mobility, reducing knee and lower back pain, and enhancing motor function.