Andro back in the early part of the decade was the generic term for all prohormones that were natural and little to no anabolic activity. These converted into active steroids in the body. Eventually someone decided to cross the gap and sell the active steroid and this first steroid was 1-Testosterone. There are a few companies that will claim credit for this, but I believe Biotest Mag-10 was the first available anabolic steroid to be sold as a supplement. Prior to that “andro” had little to no direct activity in the body and counted on conversion to “work”.