It does not require proof of efficacy in large trials the way we typically expect from drugs, but it facilitates prescribing, and that changes things a lot, because there wont be a black market anymore
B12 absorption is regulated through intrinsic factor, which is produced by gastric parietal cells in the stomach, with the B12-intrinsic factor complex being absorbed in the terminal ileum
STOCKTON, Calif
Sanz-Cuesta T, Escortell-Mayor E, Cura-Gonzalez I et al (2020) Oral versus intramuscular administration of vitamin B12 for vitamin B12 deficiency in primary care: a pragmatic, randomized, non-inferiority clinical trial (OB12)
Synthesized to 99% purity, with every lot supported by an independent Janoshik COA and full batch traceability
The pattern of consistent findings across in vitro, ex vivo, and animal-model contexts has shaped the contemporary research-context framing for the compound