The FDA has considered your own stem cells as a medication to bring it under their control - honestly that claim alone is pretty disingenuous, stem cells and properties of your blood are your body's natural healing mechanisms; with these treatments they're not changing or manipulating the stem cells, which you could more reasonably argue should be classified as a medication.
Another claim big pharma is trying to use is that injecting bone marrow into joints shouldn't be allowed because it's non-homologous - meaning that bone marrow isn't naturally in the joints, so it shouldn't be allowed to be injected - the reason they want to prevent it is because injecting stem cells into joints will clear up the pain caused by osteoarthritis.