because they are anabolic steroids, the sale of which violate the DSHEAS. Would guess the FDA has either warned or indicated enforcement action. Voluntary cessation of sale is usually better for the manufacturer, being on the bad side of the FDA is not good for someone "pushing the line". Though pretty sure that explanation is irrelevant to the end purchaser. But that is the most likely reason.
basically the FDA "realized" they were steroids (or something that meets the definition and is not covered by classification) and thus began the proccess which likely led to pulling it.
though someone from AX would have to verify that (could be another reason but that is the most likely)