Undenatured type II collagen (UC-II®) for joint support: a randomized, double-blind, placebo-controlled study in healthy volunteers

Lugo JP, Saiyed ZM, Lau FC, et al. · Journal of the International Society of Sports Nutrition

UC-II increased average knee-extension range of motion against placebo at day 120 (81.0 vs 74.0 degrees, p=0.011; 80.0 vs 73.7 in intention-to-treat, p=0.006), with no change in the placebo group at any visit and no change in knee flexion in either group. On the endpoint the trial was built around, time to exercise-induced knee pain, the gain was within the UC-II group only: 1.4 minutes at baseline to 2.8 at day 120 (p=0.019), with 'no statistically significant differences noted for either the placebo group or between groups'. A reanalysis counting the pain-free subjects at the 10-minute ceiling brought the day-120 between-group comparison to p=0.051. Five UC-II subjects and one on placebo ended the study pain-free, a difference that did not reach significance between groups (p=0.126). KOOS and the Stanford exercise scale showed nothing.

Population

Healthy adults without OA who developed knee pain during a standardized stepmill test

Intervention

UC-II 40 mg/day for 120 days

Comparator

Placebo

Limitations

Small industry-funded trial in healthy people averaging 46 years old, and range of motion is a surrogate of uncertain clinical meaning. Of 55 randomised, nine were lost to follow-up and 46 analysed. The one endpoint that separated from placebo is the surrogate; the pain endpoints did not.