They have published a lot of stuff.

I don't remember the exact link for the biochem stuff. Something about collagen being glycine limited and vitamin C being a catalyst for synthesis for tendon tissue regrowth.

Here are the two papers I remember reviewing.

https://escholarship.org/uc/item/2wn8s39q

https://escholarship.org/content/qt2j57t1j1/qt2j57t1j1.pdf