I wonder if J&J got a patent on S-ketamine? The patent system is often abused this way. First you sell the racemic mixture, then when that patent is about to expire, you start selling a new product that is just the active enantiomer. And you can tell customers that it's new and improved: that you only need to take half as much! See Prilosec/Nexium, Celexa/Lexapro, etc.
Although, maybe it's difficult to manufacture just the one enantiomer, at scale?