Assuming you replied to the wrong post but:

There have been plenty of studies over the years of initial findings. https://www.scientificamerican.com/article/new-limb-regeneration-ins/ is a recent one. And you can find plenty of others with a bit of a google.

Would I fund any company that claimed they could do it? Hell no. But this is very much the kind of topic where university research groups should be regularly getting grants to advance the state of science. And this is exactly the kind of topic where you can convert some of that massive military overspending into science and research.